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Title: The Book of Cheese
Author: Fisk, Walter Warner, Thom, Charles
Language: English
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THE BOOK OF CHEESE
* * * * *
The Rural Text-Book Series
EDITED BY L. H. BAILEY
_Carleton_: THE SMALL GRAINS.
_B. M. Duggar_: THE PHYSIOLOGY OF PLANT PRODUCTION.
_J. F. Duggar_: SOUTHERN FIELD CROPS.
_Gay_: BREEDS OF LIVE-STOCK.
_Gay_: PRINCIPLES AND PRACTICE OF JUDGING LIVE-STOCK.
_Goff_: PRINCIPLES OF PLANT CULTURE.
_Guthrie_: BOOK OF BUTTER.
_Harper_: ANIMAL HUSBANDRY FOR SCHOOLS.
_Harris and Stewart_: PRINCIPLES OF AGRONOMY.
_Hitchcock_: TEXT-BOOK OF GRASSES.
_Jeffery_: TEXT-BOOK OF LAND DRAINAGE.
_Jordan_: FEEDING OF ANIMALS. Revised.
_Livingston_: FIELD CROP PRODUCTION.
_Lyon_: SOILS AND FERTILIZERS.
_Lyon, Fippin and Buckman_: SOILS, THEIR PROPERTIES AND MANAGEMENT.
_Mann_: BEGINNINGS IN AGRICULTURE.
_Montgomery_: THE CORN CROPS.
_Morgan_: FIELD CROPS FOR THE COTTON-BELT.
_Mumford_. THE BREEDING OF ANIMALS.
_Piper_: FORAGE PLANTS AND THEIR CULTURE.
_Sampson_: EFFECTIVE FARMING.
_Thom_ and _Fisk_: THE BOOK OF CHEESE.
_Warren_: THE ELEMENTS OF AGRICULTURE.
_Warren_: FARM MANAGEMENT.
_Wheeler_: MANURES AND FERTILIZERS.
_White_: PRINCIPLES OF FLORICULTURE.
_Widtsoe_: PRINCIPLES OF IRRIGATION PRACTICE.
* * * * *
[Illustration: FIG. 1.--A cheese laboratory in the New York State
College of Agriculture at Cornell University.]
THE BOOK OF CHEESE
by
CHARLES THOM
Investigator in Cheese, Formerly at Connecticut
Agricultural College
and
WALTER W. FISK
Assistant Professor of Dairy Industry (Cheese-Making),
New York State College of Agriculture
at Cornell University
New York
The Macmillan Company
1918
All rights reserved
Copyright, 1918,
By the Macmillan Company.
Set up and electrotyped. Published July, 1918.
Norwood Press
J. S. Cushing Co.--Berwick & Smith Co.
Norwood, Mass., U.S.A.
PREFACE
Certain products we associate with the manufactures of the household, so
familiar and of such long standing that we do not think of them as
requiring investigation or any special support of science. The older
ones of us look back on cheese as an ancient home product; yet the
old-fashioned hard strong kind has given place to many named varieties,
some of them bearing little resemblance to the product of the kitchen
and the buttery. We have analyzed the processes; discovered
microorganisms that hinder or help; perfected devices and machines;
devised tests of many kinds; studied the chemistry; developed markets
for standardized commodities. Here is one of the old established farm
industries that within a generation has passed from the housewife and
the home-made hand press to highly perfected factory processes employing
skilled service and handling milk by the many tons from whole
communities of cows. This is an example of the great changes in
agricultural practice. Cheese-making is now a piece of applied science;
many students in the colleges are studying the subject; no one would
think of undertaking it in the old way: for these reasons this book is
written.
This book is intended as a guide in the interpretation of the processes
of making and handling a series of important varieties of cheese. The
kinds here considered are those made commercially in America, or so
widely met in the trade that some knowledge of them is necessary. The
relation of cheese to milk and to its production and composition has
been presented in so far as required for this purpose. The principles
and practices underlying all cheese-making have been brought together
into a chapter on curd-making. A chapter on classification then brings
together into synoptical form our knowledge of groups of varieties.
These groups are then discussed separately. The problems of factory
building, factory organization, buying and testing milk, and the proper
marketing of cheese, are briefly discussed.
Such a discussion should be useful to the student, to the beginner in
cheese-making, as a reference book on many varieties in the hands of
makers who specialize in single varieties, and to the housekeeper or
teacher of domestic science. The material has been brought together from
the experience of the writers, supplemented by free use of the
literature in several languages. Standard references to this literature
are added in the text.
No introduction to the subject of cheese should fail to mention the work
of J. H. Monrad, who has recently passed away. Mr. Monrad never
collected his material into a single publication, but his contributions
to cheese-making information, scattered widely in trade literature over
a period of thirty years, form an encyclopedia of the subject.
Bulletins of the Agricultural Experiment Stations and United States
Department of Agriculture have been quoted extensively, with citation of
the sources of the material. Personal assistance from Professor W. A.
Stocking and other members of the Dairy Department of Cornell
University, and C. F. Doane of the United States Department of
Agriculture, is gladly acknowledged.
Students cannot learn out of books to make cheese. They may, however,
be aided in understanding the problems from such study. To make cheese
successfully they must have intimate personal touch with some person who
knows cheese. Sympathetic relations with such a teacher day by day in
the cheese-room are essential to success in making cheese which, at its
best, is one of the most attractive of food-products.
THE AUTHORS.
TABLE OF CONTENTS
CHAPTER I
PAGES
GENERAL STATEMENT ON CHEESE 1-4
Nature of cheese, 1; Cheese-making as an art, 2;
Cheese-making as a science, 3; Problems in cheese-making,
4; History, 5.
CHAPTER II
THE MILK IN ITS RELATION TO CHEESE 5-28
Factors affecting the quality, 6; Chemical composition, 7;
Factors causing variation in composition, 8; Milk
constituents, 9; Water, 10; Fat, 11; Casein, 12;
Milk-sugar, 13; Albumin, 14; Ash, 15; Enzymes, 16; The
flavor of feeds eaten by the cow, 17; Absorption of odors,
18; Effect of condition of the cow, 19; Bacteria in the
milk, 20; Groups of bacteria in milk, 21; Acid
fermentation of milk, 22; Bacterium lactis-acidi group,
23; Colon-aërogenes group, 24; Acid peptonizing group, 25;
Bacillus bulgaricus group, 26; Acid cocci or weak
acid-producers, 27; Peptonizing organisms, 28; Inert
types, 29; Alkali-producing bacteria, 30; Butyric
fermenting types, 31; Molds and yeasts, 32; Bacterial
contamination of milk, 33; Germicidal effect of milk, 34;
Sources and control of bacteria in milk, 35; The cow, 36;
Stable air, 37; The milker, 38; Utensils, 39; The factory,
40; The control of bacteria, 41; Fermentation test, 42;
The sediment test, 43.
CHAPTER III
COAGULATING MATERIALS 29-40
Ferments, 44; Nature of rennet, 45; Preparation of rennet
extract, 46; Pepsin, 47; Chemistry of curdling, 48; Use
of acid, 49; Robertson's theory, 50; Rennet curd, 51;
Hammarsten's theory, 52; Duclaux theory, 53; Bang's
theory, 54; Bosworth's theory, 55.
CHAPTER IV
LACTIC STARTERS 41-54
Acidifying organisms, 56; Starter, 57; Natural starter,
58; Commercial starter or pure cultures, 59;
Manufacturer's directions, 60; Selecting milk, 61;
Pasteurization, 62; Containers, 63; Adding cultures, 64;
Cleanliness, 65; "Mother" starter or startoline, 66;
Examining starter, 67; Second day's propagation, 68;
Preparations of larger amount of starter, 69; Amount of
mother starter to use, 70; Qualities, 71; How to carry the
mother starter, 72; Starter score-cards, 73; Use of
starter, 74; The amount of starter to use, 75; Starter
lot-card, 76.
CHAPTER V
CURD-MAKING 55-80
The composition of the milk, 77; Cheese color, 78; The
acidity factor, 79; Acidity of milk when received, 80; The
acid test, 81; Rennet tests, 82; Marschall rennet test,
83; Comparison of acid and rennet test, 84; Control of
acid, 85; Acidity and rennet action, 86; Acidity and
expulsion of the whey, 87; Acidity in relation to cheese
flavor, 88; Acidity in relation to body and texture of
cheese, 89; Acidity in relation to cheese color, 90;
Control of moisture, 91; Relation of moisture to
manufacture and quality, 92; Relation of moisture to
acidity, 93; Setting temperature, 94; Strength of
coagulating materials, 95; Amount of coagulating materials
to use, 96; Method of adding rennet, 97; The curdling
period, 98; Cutting or breaking the curd, 99; Curd knives,
100; Heating or "cooking," 101; Draining, 102; Application
to cheese, 103.
CHAPTER VI
CLASSIFICATION 81-88
Basis of classification, 104; Processed cheeses, 105; Whey
cheeses, 106; Soft and hard cheeses, 107; Relation of
moisture to classes, 108; Relation of heat to classes,
109.
CHAPTER VII
CHEESES WITH SOUR-MILK FLAVOR 89-110
Skim series, 110; Cottage cheese, 111; Household practice,
112; Factory practice, 113; Buttermilk cheese, 114;
Neufchâtel group, 115; Domestic or American Neufchâtel
cheeses, 116; The factory, 117; Cans, 118; Draining racks,
119; Cloths, 120; Molding machinery, 121; Milk for
Neufchâtel, 122; Starter, 123; Renneting or setting, 124;
Draining, 125; Cooling Neufchâtel, 126; Pressing, 127;
Working and salting Neufchâtel, 128; Storage, 129;
Molding, 130; Skimmed-milk Neufchâtel, 131; Baker's
cheese, 132; Domestic Neufchâtel, 133; Partially skim
Neufchâtel, 134; Cream cheese, 135; Neufchâtel
specialties, 136; Gervais, 137; European forms
occasionally imported, 138.
CHAPTER VIII
SOFT CHEESES RIPENED BY MOLD 111-133
Hand cheese and its allies, 139; Pennsylvania pot cheese,
140; Appetitost (Appetite cheese), 141; Ripened
Neufchâtel, French process, 142; The Camembert group, 143;
Camembert cheese, 144; Description of Camembert, 145;
Conditions of making and ripening, 146; Outline of making
process, 147; Acidity, 148; Ripening the cheese, 149;
Composition, 150; Factory, 151; Economic factors, 152;
French Brie, 153; Coulommiers, 154.
CHAPTER IX
SOFT CHEESES RIPENED BY BACTERIA 134-148
The Isigny group, 155; Raffiné, 156; Liederkranz cheese,
157; Limburger cheese, 158; The milk, 159; Making the
cheese, 160; Draining and salting, 161; Ripening, 162;
Marketing and qualities of Limburger, 163; Yield and
composition of Limburger, 164; Münster cheese, 165.
CHAPTER X
SEMI-HARD CHEESES 149-171
The green mold group, 166; Roquefort cheese, 167; Cow's
milk or Façons Roquefort, 168; Outline of making
Roquefort, 169; Ripening of Roquefort, 170; Gorgonzola,
171; Stilton cheese, 172; Gex, 173; Bacterially-ripened
series, 174; Brick cheese, 175; Making of brick cheese,
176; Ripening brick cheese, 177; Qualities of brick
cheese, 178; Composition and yield, 179; Port du Salut
cheese, 180.
CHAPTER XI
THE HARD CHEESES 172-183
The Danish group, 181; The Dutch group, 182; Edam cheese,
183; Method of manufacture, 184; Salting and curing Edam,
185; Equipment for making Edam cheese, 186; Qualities and
yield of Edam cheese, 187; Gouda cheese, 188; Method of
manufacture, 189; Equipment for Gouda cheese, 190;
Composition and yield, 191.
CHAPTER XII
CHEDDAR CHEESE-MAKING 184-221
The lot-card, 192; The milk, 193; Ripening the milk, 194;
Setting or coagulating, 195; Cutting, 196; Heating or
"cooking" the curd, 197; Removing the whey, 198; Hot-iron
test, 199; Firmness of the curd, 200; Gathering the curd
together, 201; Matting or cheddaring, 202; Milling the
curd, 203; Salting, 204; Hooping the curd, 205; Pressing
the curd, 206; Dressing the cheese, 207; Handling
over-ripe and gassy milk, 208; Qualities of Cheddar
cheese, 209.
CHAPTER XIII
COMPOSITION AND YIELD OF CHEDDAR CHEESE 222-246
Composition of milk, whey and cheese, 210; Relations of
fat to casein in normal milk, 211; Influence of fat in
milk on yield of cheese, 212; Fat loss in cheese-making,
213; Effect of bacterial-content of milk on yield of
cheese, 214; Factors affecting the moisture-content of
Cheddar, 215; Variations of the Cheddar process, 216;
Cheddar-type cheese from pasteurized milk, 217; Club
cheese, 218; The stirred-curd or granular process, 219;
California Jack cheese, 220; The washed-curd process, 221;
English dairy cheese, 222; Pineapple cheese, 223; Leyden,
224; Cheddar cheese with pimientos, 225; Sage cheese, 226;
Skimmed-milk cheese, 227; Full skimmed-milk Cheddar
cheese, 228; Half skimmed-milk Cheddar cheese, 229; Yield
and qualities of skimmed-milk Cheddar cheese, 230.
CHAPTER XIV
CHEDDAR CHEESE RIPENING 247-275
Fat, 231; Milk-sugar, 232; The salts, 233; Gases, 234;
Casein or proteins, 235; Causes of ripening changes, 236;
Action of the rennet extract, 237; The action of the
bacteria, 238; Conditions affecting the rate of cheese
ripening, 239; The length of time, 240; The temperature of
the curing-room, 241; Moisture-content of the cheese, 242;
The size of the cheese, 243; The amount of salt used, 244;
The amount of rennet extract, 245; The influence of acid,
246; Care of the cheese in the curing-room, 247;
Evaporation of moisture from the cheese during ripening,
248; Paraffining, 249; Shipping, 250. _Defects in Cheddar
cheese_: Defects in flavor, 251; Feedy flavors, 252; Acid
flavors, 253; Sweet or fruity flavors, 254; Defects in
body and texture, 255; Loose or open texture, 256; Dry
body, 257; Gassy textured cheese, 258; Acidy, pasty or
soft body and texture, 259; Defects in color, 260; Defects
in finish, 261. _Cheddar cheese judging_: Securing the
sample, 262; How to determine quality, 263; Causes of
variations in score, 264; The score-card, 265.
CHAPTER XV
THE SWISS AND ITALIAN GROUPS 276-292
_Swiss cheese_: The Swiss factory, 266; The milk, 267;
Rennet extract, 268; Starter, 269; The making process,
270; Curing Swiss, 271; Block Swiss, 272; Shipment, 273;
Qualities of Swiss cheese, 274; Composition and yield,
275; _The Italian group_: Parmesan, 276; Regianito, 277.
CHAPTER XVI
MISCELLANEOUS VARIETIES AND BY-PRODUCTS 293-296
Caciocavallo, 278; Sap sago, 279; Albumin cheese, 280;
Mysost, Norwegian whey cheese, 281; Whey butter, 282.
CHAPTER XVII
CHEESE FACTORY CONSTRUCTION, EQUIPMENT, ORGANIZATION 297-310
Locating the site, 283; The building, 284; Heating plant,
285; Curing-rooms, 286; Light, 287; Ventilation, 288;
Boiler-room, 289; whey tanks, 290; Store-room, 291; The
floors, 292; Arrangement of machinery and rooms, 293;
Arrangements for cleanliness, 294; Equipment and supplies
list, 295; Factory organization, 296.
CHAPTER XVIII
HISTORY AND DEVELOPMENT OF THE CHEESE INDUSTRY IN AMERICA 311-326
The factory system, 297; Introduction of factory system in
Canada, 298; Introduction of cheddaring, 299; Introduction
of Swiss and Limburger, 300; Number and distribution of
cheese factories, 301; Total production of cheese in the
United States, 302; Rank of the leading cheese-producing
states, 303; Exportation and importation of cheese by the
United States, 304; Average yearly price of cheese, 305;
Canadian cheese statistics, 306; Introduction of
cheese-making into new regions, 307.
CHAPTER XIX
TESTING 327-342
The fat test, 308; Sampling the milk, 309; Adding the
acid, 310; Centrifuging, 311; Reading the test, 312;
testing whey for fat, 313; testing cheese for fat, 314;
Reading the test, 315; The Hart casein test, 316; Solids
in the milk, 317; the lactometer, 318; Calculating the
solids not fat in the milk, 319; Testing cheese for
moisture, 320.
CHAPTER XX
MARKETING 343-361
Buying milk, 321; Cheese yield basis of buying milk, 322;
Fat basis for payment of milk, 323; Weight basis or
pooling method for payment of milk, 324; Fat-plus-two
method for payment of milk, 325; Comparison of methods,
326; Laws governing the production and sale of milk, 327;
Marketing of cheese, 328; Mercantile exchanges, 329;
Marketing perishable varieties, 330; Distribution of
price, 331; Standards, 332; Laws relating to cheese
marketing, 333.
CHAPTER XXI
CHEESE IN THE HOUSEHOLD 362-381
Food value of cheese, 334; Digestibility of cheese, 335;
Cheese flavor, 336; Relation to health, 337; Cheese
poisoning, 338; Proper place in the diet, 339; Care of
cheese, 340; Food value and price, 341; Methods and
recipes for using cheese, 342.
THE BOOK OF CHEESE
CHAPTER I
_GENERAL STATEMENT ON CHEESE_
Cheese is a solid or semi-solid protein food product manufactured from
milk. Its solidity depends on the curdling or coagulation of part or all
of the protein and the expulsion of the watery part or whey. The
coagulum or curd so formed incloses part of the milk-serum (technically
whey) or watery portion of the milk, part of the salts, part or all of
the fat, and an aliquot part of the milk-sugar. The loss in manufacture
includes a small fraction of the protein and fat, the larger proportion
of the water, salts and milk-sugar.
+1. Nature of cheese.+--Milk of itself is an exceedingly perishable
product. Cheese preserves the most important nutrient parts of the milk
in condition for consumption over a much longer period. The duration of
this period and the ripening and other changes taking place depend very
closely on the composition of the freshly made cheese. There is an
intimate relation between the water, fat, protein and salt-content of
the newly made cheese and the ripening processes which produce the
particular flavors of the product when it is ready for the consumer.
This relation is essentially biological. A cheese containing 60 to 75
per cent of water, as in "cottage cheese" (the sour-milk cheese so
widely made in the homes), must be eaten or lost in a very few days.
Spoilage is very rapid. In contrast to this, the Italian Parmesan, with
30 to 32 per cent of water, requires two to three years for proper
ripening.
The cheeses made from soured skim-milk probably represent the most
ancient forms of cheese-making. Their origin is lost in antiquity. The
makers of Roquefort cheese cite passages from Pliny which they think
refer to an early form of that product. It is certain that cheese in
some form has been familiar to man throughout historic times. The
technical literature of cheese-making is, however, essentially recent.
The older literature may be cited to follow the historical changes in
details of practice.
+2. Cheese-making as an art+ has been developed to high stages of
perfection in widely separate localities. The best known varieties of
cheese bear the geographical names of the places of their origin. The
practices of making and handling such cheeses have been developed in
intimate relation to climate, local conditions and the habits of the
people. So close has been this adjustment in some cases, that the
removal of expert makers of such cheeses to new regions has resulted in
total failure to transplant the industry.
+3. Cheese-making as a science+ has been a comparatively recent
development. It has been partly a natural outgrowth of the desire of
emigrant peoples to carry with them the arts of their ancestral home,
partly the desire to manufacture at home the good things met in foreign
travel. Its development has been largely coincident with the development
of the agricultural school and the science of dairy biology. Even now
we have but a limited knowledge of a few of the 500 or more varieties of
cheese named in the literature. It is desirable to bring together the
knowledge of underlying principles as far as they are known.
No technical description of a cheese-handling process can replace
experience. Descriptions of appearances and textures of curd in terms
definite enough to be understood by beginners have been found to be
impossible. It is possible, however, to lay down principles and
essentials of practice which are common to the industry and form the
foundation for intelligent work. Cheese-making will be a science only as
we depart from the mere repetition of a routine or rule-of-thumb
practice and understand the underlying principles.
+4. Problems in cheese-making.+--Any understanding of these problems
calls for a working knowledge of the very complex series of factors
involved. These include the chemical composition of the milk, the nature
of rennet and character of its action under the conditions met in
cheese-making, the nature of the micro-organisms in milk, and the
methods of controlling them, their relation to acidity and to the
ripening of the cheese. To these scientific demands must be added
acquaintance with the technique of the whole milk industry, from its
production and handling on the farm through the multiplicity of details
of factory installation and organization, to those intangible factors
concerned with the texture, body, odor and taste of the varied products
made from it. Some of these factors can be adequately described; others
have thus far been handed on from worker to worker but have baffled
every effort at standardization or definition.
+5. History.+--The recorded history of the common varieties of cheese is
only fragmentary. Practices at one time merely local in origin followed
the lines of emigration. Records of processes of manufacture were not
kept. The continuance of a particular practice depended on the skill and
memory of the emigrant, who called his cheese after the place of origin.
Other names of the same kind were applied by the makers for selling
purposes. The widely known names were thus almost all originally
geographical. Some of them, such as Gorgonzola, are used for cheeses not
now made at the places whose names they bear. Naturally, this method of
development has produced national groups of cheeses which have many
common characteristics but differ in detail. The English cheeses form a
typical group of this kind.
Emigration to America carried English practices across the Atlantic. The
story of cheese-making in America has been so closely linked with the
development of the American Cheddar process that the historical aspects
of the industry in this country are considered under that head in
Chapter VIII.
CHAPTER II
_THE MILK IN ITS RELATION TO CHEESE_
The opaque whitish liquid, secreted by the mammary glands of female
mammals for the nourishment of their young, is known as milk. The milk
of the cow is the kind commonly used for cheese-making in America.
+6. Factors affecting the quality.+--The process of cheese-making begins
with drawing the milk from the udder. The care and treatment the milk
receives, while being drawn, and its subsequent handling, have a decided
influence on its qualities. The process of cheese-making is varied
according to the qualities of the milk. There are five factors that
influence the quality of the milk for cheese-making: (1) its chemical
composition; (2) the flavor of feed eaten by the cow; (3) the absorption
of flavors and odors from the atmosphere; (4) the health of the cow; (5)
the bacteria present. The first factor is dependent on the breed and
individuality of the cow. The other four factors are almost entirely
within the control of man. Of these factors, number five is of the most
importance, and is the one most frequently neglected.
+7. Chemical composition.+--The high, low and average composition of
milk is approximately as follows:
TABLE I
COMPOSITION OF MILK
--------+-------+------+--------+-------+---------+-----
| WATER | FAT | CASEIN | SUGAR | ALBUMIN | ASH
| PER | PER | PER | PER | PER | PER
| CENT | CENT | CENT | CENT | CENT | CENT
--------+-------+------+--------+-------+---------+-----
High | 88.90 | 5.50 | 3.00 | 5.00 | .72 | .73
Low | 85.05 | 3.00 | 2.10 | 4.60 | .70 | .70
Average | 87.47 | 3.80 | 2.50 | 4.80 | .71 | .72
--------+-------+------+--------+-------+---------+-----
+8. Factors causing variation in composition.+--The composition of cow's
milk varies according to several factors. The composition of the milk of
different breeds differs to such a degree that whole series of factories
are found with lower or higher figures than these averages on account of
dominant presence of particular kinds of cattle.
The following table shows the usual effect of breed on fat and total
solids of milk:
TABLE II
THE USUAL EFFECT OF BREED OF COWS ON FAT AND TOTAL
SOLIDS OF MILK
------------------+------------------------
| AVERAGES
BREED OF COWS +----------+-------------
| Fat | Total Solids
| Per Cent | Per Cent
------------------+----------+-------------
Jersey | 5.62 | 14.74
Guernsey | 5.34 | 14.70
Shorthorn | 4.17 | 13.41
Ayrshire | 3.61 | 12.72
Holstein-Friesian | 3.30 | 11.89
------------------+----------+-------------
The figures[1] in Tables I and II are compiled and averaged from a large
number of analyses made at different agricultural experiment stations.
This variation not only affects the fat, but all constituents of the
milk. While there is a difference in the composition of the milk from
cows of different breeds, there is almost as wide variation in the
composition of the milk from single cows[2] of the same breed. With the
same cow the stage of lactation causes a wide variation in the
composition of the milk.[3] As the period of lactation advances, the
milk increases in percentage of fat and other solids.
+9. Milk constituents.+--From the standpoint of the cheese-maker, the
significant constituents of milk are water, fat, casein, milk-sugar,
albumin, ash and enzymes. These will be discussed separately.
+10. Water.+--The retention of the solids and the elimination of the
water are among the chief considerations in cheese-making. Water forms
84 to 89 per cent of milk. Cheese-making calls for the reduction of this
percentage to that typical of the particular variety of cheese desired
with the least possible loss of milk solids. This final percentage
varies from 30 to 70 per cent with the variety of cheese. The water has
two uses in the cheese: (1) It imparts smoothness and mellowness to the
body of the cheese; (2) it furnishes suitable conditions for the action
of the ripening agents. To some extent the water may supplement or even
replace fat in its effect on the texture of the cheese. If the cheese is
properly made, the water present is in such combination as to give no
suggestion of a wet or "leaky" product.
+11. Fat.+--Fat is present in the milk in the form of suspended small
transparent globules (as an emulsion). These globules vary in size with
the breed and individuality of the cow and in color from a very light
yellow to a deep yellow shade as sought in butter. Milk with small fat
globules is preferred for cheese-making, because these are not so easily
lost in the process. Milk-fat is made up of several different compounds
called glycerids,[4] which are formed by the union of an organic acid
with glycerine as a base.
Fat is important in cheese-making for two reasons: (1) Its influence on
the yield of cheese; (2) its effect on the quality of the cheese. Many
of the details of cheese-making processes have been developed to prevent
the loss of fat in manufacture. The yield of cheese is almost directly
in proportion to the amount of fat in the milk; nevertheless, because
the solids not fat do not increase exactly in proportion to the fat, the
cheese yield is not exactly in proportion to the fat. The fat, however,
is a good index of the cheese-producing power of the milk.
+12. Casein.+--Cheese-making is possible because of the peculiar
properties of casein. This is the fundamental substance of cheese-making
because it has the capacity to coagulate or curdle under the action of
acid and rennet enzymes. Casein is an extremely complex organic
compound.[5] Authorities disagree regarding its exact composition, but
it contains varying amounts of carbon, oxygen, nitrogen, hydrogen,
phosphorus and sulfur, and it usually is combined with some form
of lime or calcium phosphate. It belongs to the general class of
nitrogen-containing compounds called proteins. It is present in milk in
the form of extremely minute gelatinous particles in suspension. Casein
is insoluble in water and dilute acids. The acids, when added, cause a
heavy, white, more or less flocculent precipitate. Rennet (Chapter III)
causes the casein to coagulate (curdle), forming a jelly-like mass
called curd, which is the basis of manufacture in most types of cheese.
In the formation of this coagulum (curd), the fat is imprisoned and
held. The casein compounds in the curd hold the moisture and give
firmness and solidity of body to the cheese. Casein contains the protein
materials in which important ripening changes take place. These changes
render the casein more soluble, and are thought to be the source of
certain characteristic cheese flavors.
+13. Milk-sugar.+--Milk-sugar (lactose) is present in solution in the
watery part of the milk. It forms on the average about 5 per cent of
cow's milk. Since it is in solution, cheese retains the aliquot part of
the total represented by the water-content of the cheese, plus any part
of the sugar which has entered into combination with the milk solids
during the souring process. The larger part of the lactose passes off
with the whey. Lactose[6] is attacked by the lactic-acid bacteria and by
them is changed to lactic acid. Cheeses in which this souring process
goes on quickly, soon contain a large enough percentage of acid to check
the rotting of the cheese by decay organisms. Without this souring, most
varieties of cheese will begin to spoil quickly. For each variety there
is a proper balance between the souring, which interrupts the growth of
many kinds of putrefactive bacteria, and the development of the forms
which are essential to proper ripening.
+14. Albumin.+--This is a form of protein which is in solution in the
milk. Albumin forms about 0.7 per cent of cow's milk. It is not
coagulated by rennet. Most rennet cheeses, therefore, retain only that
portion of the total albumin held in solution in the water retained, as
in the case of milk-sugar. Albumin is coagulated by heat, forming a film
or membrane upon the surface. There are certain kinds of cheese, such
as Ricotte, made by the recovery of albumin by heating.
+15. Ash.+--The ash or mineral constituents make up about 0.7 per cent
of cow's milk. This total includes very small amounts of a great many
substances. The exact form of some of the substances is still unknown.
Of these salts, the calcium or lime and phosphorus salts are most
important in cheese-making. They are partially or completely
precipitated by pasteurization. After such precipitation rennet fails to
act[7] or acts very slowly; hence pasteurized milk cannot be used for
making rennet cheese unless the lost salts are replaced, or the
condition of the casein is changed by the addition of some substance,
before curdling is attempted.
+16. Enzymes.+--Milk also contains enzymes. These are chemical ferments
secreted by the udder. They have the power to produce changes in organic
compounds without themselves undergoing any change. Minute amounts of
several enzymes are found in milk as follows: Diastase, galactase,
lipase, catalase, peroxidase and reductase. Just what part they play in
cheese-making is not definitely known.
+17. The flavor of feeds eaten by the cow.+--Undesirable flavors in the
milk are due many times to the use of feed with very pronounced flavors.
The most common of these feeds are onions, garlic, turnips, cabbage,
decayed ensilage, various weeds and the like. These undesirable flavors
reach the milk because the substances are volatile and are able to pass
through the tissues of the animal. While feed containing these flavors
is being digested, these volatile substances are not only present in
the milk, but in all the tissues of the animal. By the time the process
of digestion is completed, the volatile flavors have largely passed
away. Therefore, if the times of milking and feeding are properly
regulated, a dairy-man may feed considerable quantities of
strong-flavored products, such as turnip, cabbage and others, without
any appreciable effect on the flavor of the milk. To accomplish this
successfully, the cows should be fed immediately before or immediately
after milking, preferably after milking. This allows time for the
digestive process to take place and for the volatile substances to
disappear. If, however, milking is performed three or four hours after
feeding, these volatile substances are present in the milk and flavor
it.[8]
In the case of those plants which grow wild in the pasture, and to which
the cows have continued access, it is more difficult to prevent bad
flavor in the milk. The cows may be allowed to graze for a short time
only, and that immediately after milking, without affecting the flavor
of the milk. This will make it necessary to supplement the pasture with
dry feed, or to have another pasture where these undesirable plants do
not grow.
Undesirable flavors are usually noticeable in the milk when the cows are
turned out to pasture for the first time in the spring; and when they
are pastured on rank fall feed, such as second growth clover.
+18. Absorption of odors.+--Milk, especially when warm, possesses a
remarkable ability to absorb and retain odors from the surrounding
atmosphere.[9] For this reason, the milk should be handled only in
places free from such odor. Some of the common sources of these
undesirable odors are bad-smelling stables, strong-smelling feeds in the
stable, dirty cows, aërating milk near hog-pens, barn-yards and swill
barrels. The only way to prevent these undesirable flavors and odors is
not to expose the milk to them. The safest policy is to remove the
source of the odor.
+19. Effect of condition of the cow.+--Any factor which affects the cow
is reflected in the composition and physiological character of the milk.
(1) Colostrum. Milk secreted just before or just after parturition is
different in physical properties and chemical composition from that
secreted at any other time during the lactation period. This milk is
known as colostrum. It is considered unfit for human food, either as
milk or in products manufactured from the milk. Most states[10] consider
colostrum adulterated milk, and prohibit the sale of the product for
fifteen days preceding and for five days after parturition. (2) Disease.
When disease is detected in the cow, the milk should at once be
discarded as human food. Some diseases are common both to the cow and to
man, such as tuberculosis, foot-and-mouth disease. If such diseases are
present in the cow, the milk may act as a carrier to man. Digestive
disorders of any sort in the cow are frequently accompanied by
undesirable flavors in the milk. These are not thought to be due to the
feed, but to the abnormal condition of the cow. When the normal
condition is restored, these undesirable flavors disappear.
+20. Bacteria in the milk.+--Bacteria are microscopic unicellular
plants, without chlorophyll. Besides bacteria, there are other forms of
the lower orders of plants found in milk, such as yeasts and molds.
While the bacteria are normally the more important, frequently yeasts
and molds produce significant changes in milk and other dairy products.
Bacteria are very widely distributed throughout nature. They are so
small that they may easily float in the air or on particles of dust.
Many groups of bacteria are so resistant to adverse conditions of growth
that they may be present in a dormant or spore stage, and, therefore,
not be easily recognized; when suitable environments for growth are
again produced, development begins at once. They are found in all
surface water, in the earth and upon all organic matter. There are a
great many different groups of bacteria; some are beneficial, and some
are harmful. As they are so small, it is difficult to differentiate
between the beneficial and harmful kinds, except by the results
produced, or by a careful study in an especially equipped laboratory.
The bacteria multiply very rapidly. This is brought about by fission;
that is, the cell-walls are drawn in at one place around the cell, and
when the walls unite at the center, the cell is divided. There are then
two bacteria. In some cases, division takes place in twenty to thirty
minutes. Like other plants, they are very sensitive to food supply, to
temperature and to moisture, as conditions of growth. Inasmuch as the
bacteria are plant cells, they must absorb their food from materials in
solution. They may live on solid substances, but the food elements must
be rendered soluble before they can be used. Most bacteria prefer a
neutral or slightly acid medium for growth, rather than an alkaline
reaction. Ordinary milk makes a very favorable medium for the growth of
bacteria, because it is an adequate and easily available food supply.
In milk, certain groups of bacteria are commonly present, but many
others which happen to get into it live and multiply rapidly. A
favorable temperature is very necessary for such organisms to multiply.
There is a range of temperature, more or less wide, at which each group
of bacteria grows and multiplies with the greatest rapidity. This range
varies with the different groups, but most of them find temperatures
between 75° F. and 95° F. the most favorable for growth. Excessive heat
kills the bacteria. Low temperatures stop growth, but kill few if any
bacteria. Temperatures of 50° F. and lower retard the growth of most
forms of bacteria found commonly in milk. Many forms will slowly
develop, however, below 50° and some growth will occur down to the
freezing point. Milk held at 50° F. or lower will remain in good
condition long enough to be handled without injury to quality until
received in the cheese factory. In the place of seeds, some groups of
bacteria form spores. The spores are exceedingly resistant to
unfavorable conditions of growth, such as heat, cold, drying, food
supply and even chemical agents. This property makes it difficult to
destroy such bacteria.
+21. Groups of bacteria in milk.+--Milk when first drawn usually shows
an amphoteric reaction; that is, it will give the acid and alkaline
reactions with litmus paper. Under normal conditions, milk soon begins
to undergo changes, due to the bacteria. Changes produced in this way
are called "fermentations"; the agents causing them, "ferments."
Normally the acid fermentation takes place first, and later other
fermentations or changes begin, which, after a time, so decompose the
milk that it will not be suitable for cheese-making or human
consumption.
The following grouping of the organisms in milk is based on their
effects on the milk itself[11]:
I. Acid-producing types.
II. Peptonizing types.
III. Inert types.
IV. Alkali-producing types.
V. Butyric fermenting types.
Each type of bacteria produces more or less specific changes in the
milk. As a general rule, the predominance of one of these types is an
aid in the interpretation of the quality of the product at the time of
analysis, such as the age, the temperature at which it has been held,
the conditions under which it was produced and, in some cases, the
general source of the contamination. The reaction due to certain
bacteria is utilized in the manufacture and handling of dairy products;
other groups have deleterious effects. (See Fig. 2.)
[Illustration: FIG. 2.--Effect of different fermentations of milk: _U_,
Curd pitted with gas holes; _G_ and _O_, gassy curds which float; _K_,
smooth, solid desirable curd.]
+22. Acid fermentation of milk.+--By far the most common and important
fermentation taking place in milk is due to the action of the lactic
acid-forming bacteria on the milk-sugar or lactose. The bacteria that
bring about this fermentation may be divided into several groups on the
basis of their morphology, proteolytic activity, gas production,
temperature adaptation and production of substances other than lactic
acid. The larger number of organisms producing lactic acid in milk also
produce other organic acids in greater or less abundance. Inasmuch as
lactic acid is the principal substance produced, they are called lactic
acid organisms. This group contains different kinds of organisms which
may be subdivided into small groups as follows:
(a) _Bacterium lactis-acidi_ group.
(b) _Bacterium colon-aërogenes_ group.
(c) Acid peptonizing group.
(d) _Bacillus bulgaricus_ group.
(e) Acid cocci or weak acid-producing group.
+23. Bacterium lactis-acidi group.+--There are many strains or varieties
in this group which are closely related in their activities. They are
universally present in milk and are commonly the greatest causal agent
in its souring. They are widely distributed in nature. At a temperature
of 65° F. to 95° F., these bacteria grow and multiply very rapidly; at
70° F. (approximately 20° C.) these forms usually outgrow all others.
The total amount of acid produced in milk by these organisms varies from
0.6 of one per cent to 1 per cent acid calculated as pure lactic acid.
These forms coagulate milk to a smooth curd of uniform consistency. In
addition to the lactic acid, there are produced traces of acetic,
succinic, formic and proprionic acids, traces of certain alcohols,
aldehydes and esters. Substances other than lactic acid are not produced
by organisms of this group to such an extent as to impart undesirable
flavors to the milk. The action of this group on the milk proteins is
very slight. They produce no visible sign of peptonization. The _B.
lactis-acidi_ group of organisms are essential to the production of the
initial acidity necessary in most types of cheese. The practical culture
and utilization of them for this purpose under factory conditions are
discussed in Chapter IV, entitled "Lactic Starters."
+24. Colon-aërogenes group.+--This group takes its name from a typical
species, _Bacterium coli communis_, which is a normal inhabitant of the
intestines of man and animals, and from _Bacterium coli aerogenes_,
which is similar in many respects to _B. coli communis_. The initial
presence of these bacteria in milk is indicative of fecal contamination
or unclean conditions of production. These organisms, however, grow and
develop in milk very rapidly at high temperatures of handling. The total
acidity produced by these forms is less than that by the _Bacterium
lactis-acidi_ group. Of the acid produced, less than 30 per cent is
lactic acid; the other acids are formic, acetic, proprionic and
succinic. The large percentage of these acids, with comparatively large
amounts of certain alcohols, aldehydes and esters, invariably impart
undesirable flavors and odors to the milk. Members of this group
uniformly ferment the lactose with the production of the gases, carbon
dioxide and hydrogen. The milk is coagulated into a lumpy curd,
containing gas pockets.
+25. Acid peptonizing group.+--These are often associated with colon
organisms. The group includes those bacteria which coagulate milk with
an acid curd and subsequently partly digest it. They grow and multiply
rapidly at a temperature between 65° and 98° F. They impart undesirable
flavors and odors to the milk, which appear to be due to the formation
of acids other than lactic acid, and to action on the milk proteins.
+26. Bacillus bulgaricus group.+--These organisms grow best at a
temperature of 105° to 115° F. They will develop at lower temperatures,
but not so rapidly. They survive heating to 135° F. without loss of
vigor, as occurs in Swiss cheese-making. They produce from 1 to 4 per
cent of acid in milk, which is practically all lactic acid. They do not
produce gas. They impart no undesirable flavors to the milk.
+27. Acid cocci or weak acid-producers.+--This group of organisms is not
very well defined. It consists mostly of coccus forms, commonly found
in the air and in the udder. Their presence in the milk may indicate
direct udder contamination. These are regarded as of little importance,
unless in very large number, and they have been only partially studied.
They produce little or no lactic acid, and small amounts of acetic,
proprionic, butyric and caproic acids. These forms rarely create enough
acid to coagulate milk.
+28. Peptonizing organisms.+--This group includes all bacteria which
have a peptonizing effect on the milk. It includes the acid peptonizing
organisms, although they are of primary importance in the acid type of
bacteria, because the acid-producing power is greater than the
peptonizing power. Some of the specific organisms in this class are
_Bacillus subtilis_, _Bacterium prodigiosus_ and _Bacterium
liquefaciens_. These are commonly found in soil water and in fecal
material. The presence of these organisms denotes contamination from
such sources.
+29. Inert types.+--As the name indicates, these are organisms not known
to have an appreciable effect on milk. The ordinary tests fail to
connect them with important processes; hence they appear to feed upon,
but not to affect the milk in any serious way. Milk ordinarily contains
more or less of these organisms, but no particular significance is
attached to their presence.
+30. Alkali-producing bacteria.+--This group of organisms has only
recently been studied in relation to its action on milk. Investigators
still disagree as to the usual percentage in the normal milk flora.
Their presence in milk has been considered to be relatively unimportant.
+31. Butyric fermenting types.+--Organisms causing butyric fermentation
may be present in the milk, but seldom become active, because they are
commonly anaërobic and so will not develop in milk kept under ordinary
conditions, and the rapid growth of the lactic acid-forming bacteria
prevents their growth. These organisms act on the milk-fat, decomposing
it. Butyric acid fermentations are more common in old butter and cheese.
In these, the fermentation causes a rancid flavor.
+32. Molds and yeasts.+--The cattle feed and the air of the barn always
contain considerable numbers of yeasts and mold spores. Yeasts have been
found by Hastings[12] to cause an objectionable fermentation in
Wisconsin cheese. No further study of this group as factors in
cheese-handling has been reported. Mold spores, especially those of the
blue or green molds (Penicillum sp.) and the black molds (Mucors), are
always abundant in milk. These spores are carried into all cheeses made
from unpasteurized milk, in numbers sufficient to cover the cheeses
with mold if they are permitted to grow. Pasteurization[13] kills
most of them. The border-line series commonly referred to as the
streptothrix-actinomyces group are also very abundant in all forage and
are carried in large numbers into all milk and its products.
+33. Bacterial contamination of milk.+--When drawn from the cow, milk is
seldom if ever sterile. Organisms usually work their way from the tip of
the teat into the udder and multiply there. The fore milk usually
contains more organisms than does that drawn later. Most of the
bacterial contamination of the milk is due to the handling after it is
drawn from the cow.
+34. Germicidal effect of milk.+--Authorities agree that when a
bacterial examination of the milk is made, hour by hour, beginning as
soon as it is drawn from the cow, there is no increase in the number of
organisms for a period of several hours at first, but an actual
reduction not infrequently takes place. This is called the
"germicidal"[14] property of milk. The lower the temperature of the
milk, the longer and less pronounced is the germicidal action; the
higher the temperature, the shorter and more pronounced is this action.
This is explained as either: (1) a period of selection within which
types of bacteria entering by accident and unadapted for growth die off;
or (2) an actual weak antiseptic power in the milk-serum itself; or (3)
the forming of clusters by the bacteria and so reducing the count.
In working on a small scale or on an experimental basis, this property
at times introduces a factor of difficulty or error which is not to be
lost sight of in the selection of the milk for such purposes.
+35. Sources and control of bacteria in milk.+--Most of the bacterial
infection of milk is due to lack of care in handling. Some of the common
sources[15] of contamination are: the air in the stable; the cow's body;
the milker; the utensils; the method of handling the milk after it is
drawn from the cow; unclean cheese factory conditions.
Since bacteria cause various kinds of fermentation, not only in the
milk but in the products manufactured from it, the question of their
control is of prime importance. There are two ways in which the
bacterial growth in milk used for cheese-making may be controlled: (1)
prevention of infection; (2) the retardation of their development when
present. The former is accomplished by strict cleanliness, the latter by
adequate cooling.
+36. The cow.+--The body of the cow may be a source of bacterial
contamination. Bacteria adhere to the hair of the animal, and to the
scales of the skin, and during the process of milking these are very
liable to fall into the milk. To prevent this, the cow should be curried
to remove all loose material and hair. Just before milking, the udder
and flank should be wiped with a damp cloth; this removes some of the
material, and causes the remainder to adhere to the cow.
+37. Stable air.+--If the air of the stable is not clean, it will be a
source of contamination. Particles of dust floating in the air carry
more or less bacteria, and these fall into the milk during the process
of milking. To keep the stable air free from dust at milking time, all
operations which stir up dust, such as feeding, brushing the cows,
cleaning the floor, should be practiced after milking or long enough
before so that the dust will have settled. It is a good plan to close
the doors and to sprinkle the floor just before milking.
+38. The milker+ himself may be a source of contamination. He should be
clean and wear clean clothing. The hands should not be wet with milk
during milking.
[Illustration: FIG. 3.--Types of small-top milk pails.]
+39. Utensils.+--The utensils are an important source of bacterial
contamination. The bacteria lodge in the seams and corners unless these
are well-flushed with solder. From these seams they are not easily
removed. When fresh warm milk is placed into such utensils, the bacteria
begin to grow and multiply. All utensils with which milk comes in
contact should first be rinsed with cold water and then thoroughly
washed and finally scalded with boiling water, and drained or blown
absolutely dry. They should then be placed in an atmosphere free from
dust until wanted for use again. If an aërator is used, this should be
operated in pure air, free from odors and dust. One of the greatest
sources of bacterial contamination of cheese milk is the use of the
milk-cans to return whey to the farms for pig feed. Frequently, sour
whey is left in the cans until ready to feed. These cans are then not
properly washed and scalded. The practice of pasteurizing the whey at
the cheese factory is a great help in preventing this source of
infection and the spreading of disease.
The use of a small-top milk pail[16] is to be especially recommended in
preventing bacterial contamination. Because of the small opening,
bacteria cannot easily fall into the milk in as large numbers as when
the whole top of the pail is open. (See Fig. 3.)
If a milking machine[17] is used, great care must be exercised to see
that all parts that come in contact with the milk are cleaned after each
milking, and then put in a clean place until ready to use again.
+40. The factory.+--Another source of contamination is the cheese
factory itself. The cheese-maker should keep his factory in the cleanest
condition possible, not only because of the effect on the milk itself,
but as a stimulus for the producers to follow his example. All doors and
windows in the factory should be screened to keep out flies.
+41. The control of bacteria.+--If, in spite of preventive measures,
bacteria get into the milk, their growth can be retarded by controlling
the temperature. If the temperature of the milk, as soon as drawn, can
be reduced below that at which the bacteria grow and multiply rapidly,
it will retard their development. In general, all milk should be cooled
to 50° F. or below. In cooling the milk, it should not be exposed to
dust or odors. One of the best methods of cooling is to set the can
containing the milk into a tub of cold running water, and then stir. If
running water is not available, cold well-water[18] may be used, but the
water should be changed several times. If the milk is not stirred during
the cooling process, it will not cool so rapidly, because the layer of
milk next the can will become cold and act as an insulator to the
remainder in the center of the can.
One way to destroy many of the bacteria in milk is by pasteurization.
This consists in heating the milk to such a degree that the bacteria are
killed, and then quickly cooling it. After pasteurization, the milk is
so changed that some kinds of cheese cannot be made successfully.
+42. Fermentation test.+--When a cheese-maker is having trouble with gas
in his cheese, or bad flavors, he can generally locate the source of
difficulty. This can be done by making a small amount of cheese from
each patron's milk, called a fermentation test.[19] Pint or quart fruit
jars or milk bottles make suitable containers. They should be thoroughly
washed and scalded, to be sure they are clean and sterile, and then
covered to prevent contamination. As the milk is delivered to the
factory, a sample is taken of each patron's milk. The best way to secure
the sample is to dip the sterile jar in the can of milk as delivered and
fill two-thirds full of milk.
The jars are then set in water at 110° F. to bring the temperature of
the milk to 98° F. The jar should be kept covered. A sink or wash-tub
makes a convenient place in which to keep the jars. When the temperature
of the milk is 98° F., ten drops of rennet extract or pepsin is added to
each jar. A uniform temperature of 98° F. should be maintained in the
jars. This will necessitate the addition of warm water occasionally to
the water surrounding the jars. When the milk is coagulated, the curd is
broken up with a sterile knife. Precaution should be taken to sterilize
the knife after using it in one jar before putting it into another. The
best way to do this is to hold the knife for a minute in a pail of
boiling water, after taking it out of each jar. The same precaution
should be observed with the thermometer. Unless care is taken,
contamination is liable to be carried from one jar to the other. After
cutting, the whey is poured off. The temperature should be kept at 98°
F. so that the organisms will have a suitable temperature for growth.
The whey should be poured from the jars occasionally, usually about
every half hour.
As the fermentation takes place, different odors will be noticed in
different jars. In ten to twelve hours the jar should be finally
examined for odors and the curd taken out and cut to examine it for gas
pockets. By this means, bad flavors and gas in the cheese can be traced
to their sources.
[Illustration: FIG. 4.--A gang sediment tester, one tester removed.]
[Illustration: FIG. 5.--A single sediment tester.]
+43. The sediment test.+--The presence of solid material or dirt in the
milk is always accompanied by bacterial contamination. By means of the
sediment test, the amount of solid material can be determined. The test
consists of filtering the milk through a layer of cotton; the foreign
material is left on the cotton filter. Various devices for filtering the
milk have been manufactured. (Figs. 4 and 5.) In order to be able to
compare the filters from the different dairy-men's milk, the same amount
of each patron's milk is filtered, usually about a pint. These tests are
usually made once or twice a month at the factory and the filters placed
on a card where the dairy-men can see them. Much improvement in the
quality of the milk has been accomplished by the use of the sediment
test. The purpose of this test may be and often is defeated by the use
of efficient strainers. Milk produced in an unclean way may be rendered
nearly free from sediment if carefully strained. It must be remembered
that the strainer takes out only the undissolved substances and that
bacteria and soluble materials which constitute a very large part of the
filth pass through with the milk.
CHAPTER III
_COAGULATING MATERIALS_
At the present time, two substances are used to coagulate milk for
cheese-making,--rennet extract and commercial pepsin.[20] Many
substances will coagulate milk, such as acids and other chemicals.
Enzymes in certain plants will also coagulate it.
The curing or ripening of the cheese seems to depend on the physical and
chemical properties of the curd, on the activity of certain organisms
and on enzymes produced by them or in the milk. Rennet extract and
pepsin are the only known substances which will produce curd of such
character as will permit the desired ripening changes to take place.
Until recently, rennet extract was principally used to coagulate the
milk, but because of the scarcity, pepsin is now being substituted.
+44. Ferments.+--Many of the common changes taking place in milk are due
to fermentations. The souring of milk is one of the most familiar cases
of fermentation. The important change taking place is the formation of
lactic acid from the milk-sugar. The change is brought about by certain
living organisms, namely, the lactic acid-forming bacteria. Another
familiar case of fermentation is the coagulation of milk by rennet
extract or pepsin. In this case, the change is produced by a chemical
substance, not a living organism. Fermentation may be defined as a
chemical change of an organic compound through the action of living
organisms or of chemical agents.
There are two general classes of ferments: (1) living organisms, or
organized ferments; (2) chemical, or unorganized ferments. Organized
ferments are living microorganisms, capable, as a result of their
growth, of causing the changes. Unorganized ferments are chemical
substances or ferments without life, capable of causing marked changes
in many complex organic compounds, while the enzymes themselves undergo
little or no change. These unorganized ferments are such as rennin,
pepsin, trypsin, ptyalin. The rennet and pepsin must, therefore, be very
thoroughly mixed into the milk to insure complete and uniform results,
because they act by contact, and theoretically, if they could be
recovered, might be used over and over again. Practically, the amount
used is so small a percentage that recovery would be impractical even if
possible.
+45. Nature of rennet.+--Two enzymes or ferments are found in rennet
extract, rennin and pepsin. They are prepared from the secreting areas
of living membranes of the stomachs of mammalian young. For
rennet-making, these stomachs are most valuable if taken before the
young have received any other feed than milk. Rennin at this stage
appears to predominate over pepsin which is already secreted to some
extent. With the inclusion of other feed, the secretion of pepsin comes
to predominate. Rennin has never been separated entirely from pepsin.
Both of these enzymes are secreted by digestive glands in the same area,
perhaps even by the same glands. They are so closely related that many
workers have regarded them as identical. In practical work the
effectiveness of rennet preparations has been greatest when stomachs
which have digested feed other than milk are excluded. The differences,
therefore, however difficult to define, appear to be important in the
commercial preparation of rennet.
It was the practice until a few years ago for each cheese-maker to
prepare his own rennet extract. Each patron was supposed to supply so
many rennets. Now commercial rennet extract and pepsin are on the
market; however, some Swiss cheese-makers prefer to make their own
rennet extract. For sheep's and goat's milk cheese, some makers hold
that rennet made from kid or lamb stomachs is best for handling the milk
of the respective species. The objection to the cheese-maker preparing
his own rennet extract is that it varies in strength from batch to batch
and is liable to spoil quickly. Taints and bad odors and flavors develop
in it and so taint the cheese.
+46. Preparation of rennet extract.+--This extract may be manufactured
commercially from digestive stomachs of calves, pigs or sheep. An animal
is given a full meal just before slaughtering; this stimulates a large
flow of the digestive juices, containing the desired enzymes.
The stomach is taken from the animal, cleaned, commonly inflated and
dried. It may be held in the dry condition until needed for use. Such
stomachs are usually spoken of as "rennets" in the trade. Such old
rennets may be seen to-day hanging from the rafters of some of the older
cheese factories. When wanted for use, rennets are placed in oak barrels
and covered with water. Before placing them in the barrel, they are cut
open so that the water may have easy access. Salt is usually added to
the water at the rate of 3 to 5 per cent. They are stirred and pounded
in this solution from five to seven days. At the end of this time, they
are wrung through a clothes-wringer to remove the liquid. The rennets
are put back into a fresh solution of salt and water, the object being
to obtain all the digestive juices possible. They are usually soaked
from four to six weeks. At the end of this time, most of the digestive
juices will have been removed. The liquid portion is passed through a
filter made of straw, charcoal and sand. When clean, an excess of salt
is added to preserve it.
Such extracts cannot be sterilized by heat because the necessary
temperature would destroy the enzyme. Effective disinfectants cannot be
used in food products. The extract, therefore, should be kept cool to
retard bacterial growth. The extract is kept in wooden barrels, stone
jugs or yellow glass bottles to protect it from light, which is able to
destroy its activity. Rennet extract should be clear, with a clean salty
taste and a distinct rennet flavor. There should be no cloudy appearance
and no muddy sediment in properly preserved rennet. Rennet extract is on
the market in the form of a liquid and a powder, the former being much
more common. The commercial forms of rennet have the advantage in the
skill used in their preparation and standardization. The combined
product from large numbers of stomachs may not be as effective a
preparation as the most skillfully produced sample from the very
choicest single stomach, but it gives a uniformity of result which
improves the average product greatly.
+47. Pepsin.+--Pepsin is on the market in several commercial forms, as a
liquid, scale pepsin and in a granular form known as spongy pepsin. Some
commercial concerns put out a preparation which is a mixture of rennet
extract and commercial pepsin.
+48. Chemistry of curdling.+--The chemistry of casein[21] and of curd
formation under the influence of acid and rennet extract and pepsin has
been the subject of many years' research. While many points remain
unsettled, the general considerations together with a large mass of
accepted facts may be presented and some of the unsolved problems
pointed out as left for future researches.
Casein is a white amorphous powder, practically insoluble in water. It
is an acid and as such readily dissolves in solutions of the hydroxides
or the carbonates of alkalies and alkaline earths by forming soluble
salts.
Pure casein salt solutions and fresh milk do not coagulate on boiling,
but in the presence of free acid coagulation may take place below the
boiling temperature. The coagulum formed in the case of milk includes
fat and calcium phosphate. The slight pellicle which coats over milk
when it is warmed is of the same composition.
+49. Use of acid.+--A commonly accepted explanation of the precipitation
of casein by acids is that the casein is held in solution by chemical
union with a base (lime in the case of milk); that added acid removes
the base, allowing the insoluble casein to precipitate; and that excess
of acid unites with casein, forming a compound which is more or less
readily soluble.
+50. Robertson's theory.+--According to Robertson's conception, in a
soluble solution of a protein or its salt, the molecules of the protein
unite with each other to a certain extent, in this way forming polymers.
The reaction is reversible, and the point of equilibrium between the
compound and its polymeric modification varies under the influence of
whatever condition affects the concentration of the protein ions.
Addition of water, or of acid, alkali or salt, or the application of
heat has such an effect, and consequently alters the relative number of
heavier molecule-complexes. Robertson's experiments give evidence that
one of the effects of increase of temperature on a solution of casein is
a shifting of the equilibrium in the direction of the higher complexes.
He explains coagulation as being a result of these molecular aggregates
becoming so large as to assume the properties of matter in mass and to
become practically an unstable suspension and then a precipitate. The
acid curd then is casein or some combination of casein with the
precipitant acid.
+51. Rennet curd.+--Rennet extract and pepsin coagulation differs from
coagulation by acids, and cannot be looked on as a simple removal of the
base from a caseinate. The presence of soluble calcium salts (or other
alkaline earth salts) seems to be essential, and the precipitate formed
is not casein or a casein salt, but a salt of a slightly different
nucleoalbumin called "paracasein." Many writers, following Halliburton,
call this modification produced by rennin the "casein" and that from
which it is derived, "caseinogen." Foster and a few others have used the
term "tyrein" for the rennet clot.
A number of investigations have been made on the conditions essential or
favorable to formation of the coagulum, especially with regard to the
effects of the degree of acidity and of conditions affecting the amount
of calcium present, either as free soluble salt or bound to the casein.
Soluble salts of calcium, barium and strontium favor or hasten
coagulation, while salts of ammonium, sodium and potassium retard or
prevent coagulation.
The bulk of the coagulum from milk is a calcium paracaseinate, but it
carries down with it calcium phosphate and fat, both of which bodies
have been helped to remain in their state of suspension in milk by the
presence of the casein salt. Lindet (1912) has concluded that about
one-half of the phosphorus contained in the rennet curd is in the form
of phosphate of lime (probably tricalcic), the other half being
organically combined phosphoric acid.
+52. Hammarsten's theory.+--According to Hammarsten (1877, 1896), whose
view has been commonly held, the distinctive effect of the ferment is
not precipitation but the transformation of casein into paracasein. This
is evidenced by the fact that if rennet be allowed to act on solutions
free from lime salts no precipitate occurs; but there is an invisible
alteration of the casein, for now, even if the ferment be destroyed by
boiling the solution, addition of lime salts will cause immediate
coagulation. (See also Spiro, 1906.) Hence the process of rennet
coagulation is a two-phase process; the first phase is the
transformation of casein by rennin, the second is the visible
coagulation caused by lime salts.
Furthermore, if the purest casein and the purest rennin were used,
Hammarsten always found after coagulation that the filtrate contained
very small amounts of a protein. This protein he designated as the "whey
protein."
In accordance with these observations, Hammarsten (1911) explains the
rennin action "as a cleavage process, in which the chief mass of the
casein, sometimes more than 90 per cent, is split off as paracasein, a
body closely related to casein, and in the presence of sufficient
amounts of lime salts the paracasein-lime precipitates out while the
proteose-like substance (whey-protein) remains in solution."
By continued action of rennin on paracasein, a further transformation
has been found in several cases (Petry, 1906; Van Herwerden, 1907; Van
Dam, 1909), but perhaps due to a contamination of the rennin with
pepsin, or to the identity of these two enzymes. The action which forms
paracasein and whey-protein takes place in a short time (Hammarsten,
1896; Schmidt-Nielson, 1906). The composition and solubilities of
paracasein have received considerable attention. (See Loevenhart, 1904;
Kikkoji, 1909; Van Slyke and Bosworth, 1912.) It is more readily
digested by pepsin-hydrochloric acid than is casein (Hosl, 1910).
+53. Duclaux theory.+--Duclaux (1884) and Loevenhart (1904) and others
do not accept Hammarsten's theory; but to most workers it seems
probable, at least, that the action of the rennin is to cause a cleavage
of casein with formation of paracasein. However, the chemical and
physical differences observed between casein and paracasein appear to be
so slight that Loevenhart and some others think that they are only
physical, perhaps differences in the size of the colloid or solution
aggregates. Loevenhart conceives of a large part of the work of the
rennet (or of the acid, in acid and heat coagulation) as being a freeing
of the calcium to make it available for precipitation. Some think that
the aggregates of paracasein are larger than those of casein, but there
is more evidence of their being smaller, which idea corresponds with the
findings of Bosworth, though he looks on the change as a true cleavage.
+54. Bang's theory.+--Another description of the precipitation is given
by Bang (1911), who studied the progress of the coagulation process by
means of interruptions at definite intervals. His observations confirm
the idea that rennin causes the formation of paracasein, and that the
calcium salt serves only for the precipitation of the paracasein; the
rennin has to do also with the mobilizing of lime salts. According to
Bang, before coagulation occurs, paracaseins with constantly greater
affinity for calcium phosphate are produced. These take up increasing
amounts of calcium phosphate, until finally the combination formed can
no longer remain in solution.
+55. Bosworth's theory.+--By a very recent work of L. L. Van Slyke and
A. W. Bosworth (Van Slyke and Bosworth, 1912, 1913; and Bosworth and Van
Slyke, 1913), in which ash-free casein and paracasein were compared as
to their elementary composition, and as to the salts they form with
bases, and the properties of these salts, it is indicated that the two
compounds are alike in percentage composition and in combining
equivalent, the paracasein molecule being one-half of the casein
molecule. Moreover, Bosworth (1913) has shown that, if the rennin
cleavage be carried out under conditions which avoid autohydrolysis, no
other protein is formed; also that, if the calcium caseinate present be
one containing four equivalents of calcium, the paracaseinate does not
precipitate, save in the presence of a soluble calcium salt, while, if
the calcium caseinate be one of two equivalents of base, rennin does
cause immediate coagulation. Bosworth concludes that the rennin action
is a cleavage (probably hydrolytic) of a molecule of caseinate into two
molecules of paracaseinate, the coagulation being a secondary effect due
to a change in solubilities, dicalcium paracaseinate being soluble in
pure water but not in water containing more than a trace of calcium
salt, and the monocalcium caseinate being insoluble in water. The alkali
paracaseinates, as well as caseinates, are soluble. This explanation
seems to promise to harmonize the observations with regard to acidity
and the effects of the presence of soluble salts. This theory
represents, therefore, many years of continuous work at the New York
Experiment Station centered primarily on American Cheddar cheese.
Disputed points remain for further study but these workers have
contributed much toward a clear description of the chemical constitution
of casein as affected by rennet action and bacterial activity.
The investigations of these authors and of Hart with regard to the
changes which the paracasein, the calcium and the phosphorus undergo
during the ripening of cheese (Van Slyke and Hart, 1902, 1905; Van Slyke
and Bosworth, 1907, 1913; Bosworth, 1907) contributed to this
interpretation.
BANG, IVAR, Ueber die chemische Vorgang bei der
Milchgerinnung durch Lab, Skand. Arch. Physiol. 25, pages
105-144; through Jahresb. u. d. Fortsch. d. Thierchem.
41, pages 221-222, 1911.
BOSWORTH, A. W., The action of rennin on casein, N. Y.
Exp. Sta. Tech. Bul. 31, 1913.
BOSWORTH, A. W., Chemical studies of Camembert cheese, N.
Y. Exp. Sta. Tech. Bul. 5, 1907.
BOSWORTH, A. W., and L. L. VAN SLYKE, Preparation and
composition of basic calcium caseinate and paracaseinate,
Jour. Biol. Chem. Vol. 14, pages 207-210, 1913.
DUCLAUX, ÉMILE, Action de la présure sur le lait, Compt.
Rend. Acad. Sci. 98, pages 526-528, 1884.
HAMMARSTEN, OLOF, Zur Kenntnis des Caseins und der
Wirkung des Labfermentes, Nova. Acta Regiae Soc. Sci.
Upsaliensis in Memoriam Quattuor Saec. ab Univ.,
Upsaliensi Peractorum, 1877.
HAMMARSTEN, OLOF, Ueber das Verhalten des Paracaseins zu
dem Labenzyme, Zeit. physiol. Chem. 22, pages 103-126,
1896.
HAMMARSTEN, OLOF, A text book of physiological chemistry,
from the author's 7th German edition, 1911.
HOSL, J., Unterschiede in der tryptischen und peptischen
Spaltung des Caseins, Paracaseins und des
Paracaseinkalkes aus Kuh- und Ziegenmilch, Inaug. Diss.
Bern., 31 pp., 1910.
KIKKOJI, T., Beitrage zur Kenntniss des Caseins und
Paracaseins, Zeit. physiol. Chem. No. 61, pages 130-146,
1909.
LINDET, L., Solubilité des albuminoides du lait dans les
éléments du sérum; rétrogradation de leur solubilité sous
l'influence du chlorure, Bul. Soc. Chim. (ser. 4) 13,
pages 929-935.
LINDET, L., Sur les éléments mineraux contenus dans la
caseine du lait, Rep. Eighth Internat. Congr. of Applied
Chem. 19, 199-207, 1912.
LOEVENHART, A. S., Ueber die Gerinnung der Milch, Zeit.
physiol. Chem. 41, pages 177-205, 1904.
PETRY, EUGEN, Ueber die Einwirkung des Labferments auf
Kasein, Beitrage z. Chem. Physiol. u. Path. 8, pages
339-364, 1906.
ROBERTSON, T. BRAILSFORD, On the influence of temperature
upon the solubility of casein in alkaline solutions,
Jour. Biol. Chem. 5, pages 147-154, 1908.
SCHMIDT-NIELSON, SIGVAL, Zur Kenntnis des Kaseins und der
Labgerinnung, Upsala läkaref. Förh. (N. F.) No. 11,
Suppl.
Hammarsten Festschrift No. XV, 1-26; through Jahresb. u.
d. Fortschr. d. Thierchem. No. 36, pages 255-256, 1906.
SPIRO, K., Beeinflussung und Natur des Labungsvorganges,
Beitrage z. Chem. Physiol. u. Path. 8, pages 365-369,
1906.
VAN DAM, W., Ueber die Wirkung des Labs Auf.
Paracaseinkalks, Zeit. physiol. Chem. No. 61, pages
147-163, 1909.
VAN HERWERDEN, M., Beitrag zur Kenntnis der Labwirkung
auf Casein, Zeit. physiol. Chem. 52, pages 184-206, 1907.
VAN SLYKE, L. L., and A. W. BOSWORTH, I. Some of the
first chemical changes in Cheddar cheese. II. The acidity
of the water extract of Cheddar cheese, N. Y. Exp. Sta.
Tech. Bul. 4, 1907.
VAN SLYKE, L. L., and A. W. BOSWORTH, Composition and
properties of some casein and paracasein compounds and
their relations to cheese, N. Y. Exp. Sta. Tech. Bul. 26,
1912.
VAN SLYKE, L. L., and A. W. BOSWORTH, Method of preparing
ash-free casein and paracasein, Jour. Biol. Chem. Vol.
14, pages 203-206, 1913.
VAN SLYKE, L. L., and A. W. BOSWORTH, Preparation and
composition of unsaturated or acid caseinates and
paracaseinates, _Ibid._ Vol. 14, pages 211-225, 1913.
VAN SLYKE, L. L., and A. W. BOSWORTH, Valency of
molecules and molecular weights of casein and paracasein,
_Ibid._ Vol. 14, pages 227-230, 1913.
VAN SLYKE, L. L., and A. W. BOSWORTH, Composition and
properties of the brine-soluble compounds in cheese,
Jour. Biol. Chem. 14, pages 231-236, 1913.
VAN SLYKE, L. L., and E. B. HART, A study of some of the
salts formed by casein and paracasein with acids; their
relations to American Cheddar cheese, N. Y. Exp. Sta.
Bul. 214, 1902.
VAN SLYKE, L. L., and E. B. HART, Casein and paracasein
in some of their relations to bases and acids, American
Chem. Jour. 33, pages 461-996, 1905.
VAN SLYKE, L. L., and E. B. HART, Some of the relations
of casein and paracasein to bases and acids, and their
application to Cheddar cheese, N. Y. Exp. Sta. Bul. 261,
1905.
CHAPTER IV
_LACTIC STARTERS_
Acidity in cheese-making arises almost exclusively from the lactic acid
produced from the fermentation of milk-sugar (lactose) by bacteria.
Hydrochloric acid is used in the Wisconsin[22] process of making
pasteurized milk cheese and sometimes for making skimmed-milk curd for
baking purposes. It is regularly used in precipitating casein not for
food but for manufacturing purposes.
+56. Acidifying organisms.+--Many species of bacteria have been shown to
possess the power to produce lactic acid by fermenting lactose. In
practice, however, the cheese-maker seeks to control this fermentation
by the actual introduction of the desired organisms and by the
production of conditions which will insure this dominance through
natural selection. For this purpose the initial souring for most types
of cheeses is produced by some variety of the species originally
described by Esten[23] and commonly referred to as _Bacterium
lactis-acidi_, but variously named as _B. acidi-lactici_, _Streptococcus
lacticus_, _B. guntheri_ by different authors. Organisms of this series
dominate all other species in milk which is incubated at 70° F. They
produce a smooth solid mass without a sign of gas holes and without the
separation of whey from the curd, and develop in milk a maximum acidity
of about 0.90 of one per cent when titrated as lactic acid. (For
titration see Chapter V.) This species is usually present in small
numbers in fresh milk. There are many varieties or strains of the
species with differing rates of activity and measurable differences in
acid produced but with approximately the same qualitative characters.
Most commercial starters for cheese- and butter-making belong to this
group of species, although special mixtures with other organisms are
prepared for special purposes. In addition to this group, most varieties
of cheese contain some members of the colon-aërogenes group. When the
milk is in proper condition, the activity of this group should be held
in check by the early and rapid development of acid. Free development of
members of this group usually shows itself in the presence of gas holes
in the curd.
+57. Starter.+--The practice of using pure cultures in cheese-making has
brought about the development of factory methods of producing day by day
cultures of the organisms desired, in quantities sufficient to inoculate
the total quantity of milk used in manufacture. For this purpose milk is
mostly used and the product is known as "starter." For cheese-making
purposes, a starter is a substance used in the manufacture of dairy
products having a predominance of lactic acid-forming microorganisms in
an active state. There are two general classes of starter: (1) Natural
starter; (2) commercial starter.
+58. Natural starter.+--Milk, or other similar substance, which has
become sour or in which large numbers of lactic acid-forming organisms
are present, is called a natural starter when used in the manufacture of
dairy products. To secure clean-flavored milk, the cheese-maker usually
selects the milk of some producer who usually brings good milk and
allows it to sour naturally for use the next day. There is often a
variation from day to day in the milk delivered by the same producer, so
that the cheese-maker is not certain of a uniform quality in his
fundamental material. While the lactic acid-forming organisms are
developing, other organisms may also be present in numbers sufficient to
produce bad flavors. If a starter has any objectionable flavor, it
should not be used. Natural starters very commonly develop objectionable
flavors which at first are very difficult to recognize. When natural
starters with objectionable but not easily recognizable odors are used,
the effect may be seen on the cheese. Milk, sour whey and buttermilk are
materials commonly used as natural starter. A common difficulty in
skimmed-milk cheese is caused by the use of buttermilk as a starter.
+59. Commercial starter or pure cultures.+--The alternative practice
consists in the introduction of pure cultures of known strains of lactic
bacteria into special milk to make the starter. Since these cultures
must be prepared by a bacteriologist, commercial laboratories have
developed a large business in their production. Many such commercial
brands are manufactured under trade-marked names. Some of these cultures
represent races of lactic bacteria cultivated and cared for efficiently,
hence uniformly valuable over long periods of time. Others carelessly
produced are worthless, or even a peril to the user.
These organisms are usually shipped in small quantities in bottles of
liquid or powder, or in capsules of uniform size. The contents may be
either the culture medium upon which the organisms grew or inert
substance designed merely to hold the bacteria in inactive form. In
either solid or liquid form, the producer of the culture should
guarantee its activity up to a plainly stated date.
It is the problem[24] of the cheese-maker or butter-maker to increase
this small amount of lactic acid-forming organisms to such numbers and
in such active condition that it may be used in the factory; while being
built up, these organisms must be kept pure. The usual practice is to
allow them to develop in some material, usually whole milk or
skimmed-milk; dissolved milk powder may be used in the place of milk.
+60. Manufacturer's directions.+--The manufacturer usually sends
directions with his starter preparation, telling how it should be used
to secure the best result. These directions apply to average conditions
and must be varied to suit the individual instances so that a good
starter will be the result. The directions usually state the amount of
milk necessary for the first inoculation. It is usually a small amount,
one or two quarts. After the specific amount has been selected, this
milk should be pasteurized.
+61. Selecting milk.+--The milk for use in starter-making should be
selected with very much care. Only clean-flavored sweet milk, free from
undesirable micro-organisms, should be used in the preparation of
starter. The milk is ordinarily chosen from a producer whose milk is
usually in good condition. The quality of the milk can be determined by
the use of the fermentation test. (See Chapter II.) It is better to
choose only the morning's milk for the making of starter, because the
bacteria have not had so much opportunity to develop. In no case should
the mixed milk be used in the preparation of starter, as this eliminates
all opportunity for selection. The flavor of the starter will be the
same as that of the milk from which it is made.
+62. Pasteurization+ is the process of heating to a high temperature for
a given length of time and quickly cooling. It kills most of the
micro-organisms in the milk. In other words, it makes a clean seed-bed
for the pure culture. The temperatures of pasteurization recommended for
starter-making differ with the authority. A temperature of 180° F. for
thirty minutes or longer seems to be very satisfactory, since under
these conditions nearly all the micro-organisms in the milk are killed.
+63. Containers.+--Various kinds of containers may be used for
starter-making. One-quart glass fruit jars or milk bottles make very
satisfactory containers, because the condition of the starter may be
seen at any time. They are also easily cleaned. They have the
disadvantage, however, of being easily broken, if the temperature is
suddenly changed, or if severely jarred. Tin containers may also be
used. Such containers are not easily broken, but they are harder to
clean and must be opened to examine the contents; hence the liability of
contamination is very much greater.
This small amount of milk may be pasteurized by placing the container in
water heated to the desired temperature. A very satisfactory arrangement
is to cut of a barrel, and place a steam pipe in it. The barrel can then
be filled partly full of water and heated by steam. The bottles of milk
to be pasteurized are hung in the water in the barrel. Two or three
more bottles should be prepared than it is expected will be used as some
of the bottles are liable to be broken while cooling or heating. The
bottles should be filled about two-thirds full. This leaves room enough
to add the mother starter and later to break up the starter to examine
it. It is desirable not to have the milk or starter touch the cover
since contaminations are more likely. It is a good plan when
pasteurizing to have one bottle as a check. This may be filled with
water and left open and the thermometer placed in it. A uniform
temperature may be obtained by shaking the bottles.
+64. Adding cultures.+--After being pasteurized, the milk should be
cooled to a temperature of 80° F. This is a suitable temperature for the
development of the lactic acid-forming organisms. The commercial or pure
culture should now be added to the milk at the rate specified in the
directions. Care should be exercised in opening bottles not to put the
covers in an unclean place. A sterile dipper is a good place to put
them. After the culture has been added to the milk, it should be mixed
thoroughly by shaking the bottle. This should be repeated every fifteen
or twenty minutes for four or five times. This is done to make certain
that the culture is thoroughly mixed with the milk. The milk should be
placed in a room or incubator as near 80° F. as possible, in order to
have a uniform temperature for the growth of the organisms. The bacteria
in the pure culture are more or less dormant so that a somewhat higher
temperature than the ordinary is necessary to stimulate their activity.
This milk should be coagulated in eighteen to twenty-four hours,
depending largely on the uniformity of the temperature during
incubation.
+65. Cleanliness.+--To produce a good starter, great care should be
exercised that all utensils coming in contact with the milk are sterile.
After the milk is in the container in which the starter is made, it
should be kept covered as continuously as possible. Thermometers should
not be put into it to ascertain the temperature. When examining the
starter, do not dip into it, but pour out, as this prevents
contamination. The cover, when removed from the container, should be put
in a sterile place in such way that the dirt will not stick to it and
later get into the starter.
+66. "Mother" starter or startoline.+--The thickened sour milk obtained
by inoculating the sweet pasteurized milk with pure culture of lactic
acid-forming bacteria is known as "mother starter" or "startoline."
+67. Examining starter.+--This starter should be examined carefully as
to physical properties, odor and taste. The coagulation should be
smooth, free from whey and gassy pockets or bubbles. Sometimes the first
few inoculations from a new culture will show signs of gas, but,
usually, this will quickly disappear, and not injure the starter. It
should have a clean sour cream odor and clean, mild, acid flavor. After
breaking up it should be thick and creamy, entirely free from lumps.
This starter may have an objectionable flavor, due to the media in which
the organisms were growing when shipped. In such cases it is necessary
to carry the starter one or two propagations to overcome the flavor, to
enliven the micro-organisms and to secure the quantity desired.
+68. Second day's propagation.+--For the second day, the milk for the
starter is selected as on the first day. It is pasteurized, and this
time cooled to 70° F. The milk is cooled a trifle colder the second day
than the first, because the organisms have become more active and hence
do not require as high a temperature to grow. Instead of inoculating
with powder, as was done the first day, the mother starter prepared the
first day is used. This requires only a very small amount, perhaps a
tablespoonful to a quart bottle. It should be thoroughly mixed with the
milk. This starter may have the flavor of the media used in the
laboratory culture, therefore may need to be carried one or two days
more to eliminate it. After the flavor has become normal, the mother
starter is ready for commercial use.
[Illustration: FIG. 6.--An improved starter-can.]
+69. Preparation of larger amount of starter.+--The first thing to
determine is the quantity of starter required. As much milk should be
carefully chosen as the amount of starter desired. This milk should then
be pasteurized. An improved starter-can (Fig. 6) may be used in the
pasteurization of the milk and the making of starter, or a milk-can
(Fig. 7) placed in a tub of water in which there is a steam pipe. The
former requires mechanical power to operate the agitator, but the latter
can be used where mechanical power is not available. In the latter the
milk and starter are stirred by hand. This is the kind of apparatus more
often found in cheese factories.
[Illustration: FIG. 7.--A simple device for the preparation of starter.]
If possible, this milk should be pasteurized to 180° F. for thirty
minutes; this kills most of the bacteria and spores. The milk should be
cooled to 60°-65° F., the temperature of incubation. This temperature
may be varied with conditions, so that the starter will be ready for use
at the desired time. The higher the temperature, the less time is
required to ripen the starter.
+70. Amount of mother starter to use.+--The mother starter prepared the
day before is now used to inoculate the starter milk. The amount to use
will depend on:
1. Temperature of milk when mother starter is added;
2. Average temperature at which the milk will be kept during the
ripening period;
3. Time allowed for starter to ripen before it is to be used;
4. Vigor and acidity of the mother starter added. There is a very wide
range as to the amount of mother starter required, from 0.5 of one per
cent to 10 per cent being used under different conditions.
Some operators prefer to add the mother starter while the milk is at a
temperature of about 90° F., before it has been cooled to the incubating
temperature. This reduces the amount of mother starter necessary.
If an even incubating temperature can be maintained, it will require
less mother starter than if the temperature goes down.
If the ripening period is short, it will require a larger amount of
mother starter, than if the ripening period is longer. If the starter
has a low acidity or weak body indicating that organisms are of low
vitality, it will require more mother starter.
+71. Qualities.+--The starter, when ready to use, may or may not be
coagulated; a good idea of the quality of the starter may be gained by
the condition of the coagulation. The coagulation should be jelly- or
custard-like, close and smooth, entirely free from gas pockets and
should not be wheyed off.
When broken up, the starter should be of a smooth creamy texture and
entirely free from lumpiness or wateriness. It should have a slightly
pronounced acid aroma. The starter should be free from taints and all
undesirable flavors; the flavor should be a clean, mild acid taste.
+72. How to carry the mother starter.+--Some mother starter must be
carried from day to day to inoculate the large starter. This may be
carried or made in several ways:
1. Independently: By this method a mother starter is made and carried
entirely separately from the large starter. It requires more time and
work, but is by far the best method. With a good mother starter, there
is not so much danger of the larger starter becoming poor in quality.
2. Mother starter may be made by dipping pasteurized milk from that
prepared for the large starter with sterile jars and then inoculating
these jars separately. By this method, if the milk selected for the
large starter is poor, the mother starter for the next day will be the
same. It is very difficult by this method to carry a uniform, high
quality mother starter.
There is danger that the container used for the mother starter may not
be sterile, and there is also danger of contamination in transferring
the milk.
3. Another practice is to hold over some of the large starter used
to-day for mother starter. This is by far the easiest method. By this
practice, there is no certainty of the quality of the starter, because
there is little or no control of the mother starter. If the large
starter is for some reason not good, there is no separate reserve of
mother starter on which to rely.
+73. Starter score-cards.+--The use of a score-card tends to analyze the
observations in such a way as to emphasize all the characteristics
desired in the starter. Such an analysis seeks to minimize the personal
factor and produce a standardization of the quality. The score-card
finally reduces the qualities of the starter to a numerical basis for
ease of comparison. Many score-cards have been proposed but the one
preferred by the authors is that used by the Dairy Department of the New
York State College of Agriculture, which is as follows:
CORNELL SCORE-CARD
Flavor 50 Clean, desirable acid.
Aroma 20 Clean, agreeable acid. No undesirable aroma.
Acidity 20 0.6 per cent-0.8 per cent.
Body 10 Before breaking up: jelly-like, close,
absence of gas holes. No free
whey. After breaking up:
smooth, creamy, free from granules
or flakes.
The qualities mentioned in this score-card can be quickly and easily
determined by examining and tasting the starter and by making an acid
test of a sample. The acid test is conducted as with milk (see Chapter
II) except the starter must be rinsed out of the pipette with pure
water. Some starter score-cards call for a bacterial examination and
counting of the starter organisms. This takes a considerable period of
time and is not entirely necessary. The physical properties and acid
test are closely correlated with the presence of the desired organisms.
+74. Use of starter.+--If all milk could be clean and sweet and the only
fermentation from it were the clean acid type, a starter would be
useless. Such milk is hard to obtain; therefore, a starter is used to
overcome the bad fermentation. This improves the flavor, body and
texture of the cheese. The common contaminations which the starter will
tend to correct are:
1. Gas-producing bacteria.
2. Yeasts.
3. Bad flavors or taints.
The length of time a starter may be carried depends on the accuracy and
carefulness of the maker. This calls for scrupulous attention to the
temperature, the selection of milk and keeping out contaminations. The
maker must remember that a starter is not merely milk, but milk full of
a multitude of tiny plants, very sensitive to food, temperature, clean
surroundings and the quantity of their own acid.
NEW YORK STATE COLLEGE OF AGRICULTURE AT CORNELL UNIVERSITY
+STARTER LOT-CARD+ +Department of Dairy Industry.+
==================================================================
Day and Date_____________________
+MILK:+
Kind________________ % fat_____% solids not fat_____
Flavor__________________________________
Amount of milk____________ Hours old______________
+PASTEURIZATION:+
Method______________________________________________
Milk when received: Temperature_____ °
Acidity_____ %
Heating: Turning on heat__________ APM.
Desired temp. reached__________ APM.
Turning off heat__________ APM.
Length of time at desired temp.__________
Beginning to cool__________
Cooled__________ APM; to__________ °
Acidity: After pasteurization__________
When inoculated________________
+INOCULATION:+
Time__________ Temperature__________
Amount__________ lbs. __________%
+INCUBATION:+
Temperature__________ Time__________
+MOTHER STARTER USED:+
Source_____________________________________ % used_______________
Times propagated___________________________ Acidity______________
Amount used________________________________ Appearance___________
Flavor_______________________________
Comments__________________________________________________________
+STARTER:+
Time of examining__________
Temperature________________
+SCORE-CARD:+
Flavor__________50| Clean, desirable acid.
|
Aroma___________20| Clean, agreeable acid. No undesirable aroma.
|
Acidity_________20| 0.6%-0.75%.
|
Body____________10| Before breaking up: jelly-like, close,
| absence of gas holes. No free whey.
____| ___After breaking up: smooth, creamy, free from
| granules or flakes.
Total_________ 100|
-----------------------------------
The above is a tentative score-card.
+COMMENTS:+____________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
+Work and observation by+______________________________________
+75. The amount of starter to use+ depends on the amount of acid desired
in the milk for any particular kind of cheese. The great abuse of
starter is the practice of using too much. It is better and safer to add
starter a little at a time and several times than to add too much at
once. When starter is added to milk for cheese-making, it should be
strained to remove any lumps; otherwise an uneven color is likely to
result.
+76. Starter lot-card.+--For certain dairy operations, a permanent
record is desired. This is especially true in the making of starter and
certain varieties of cheese. A lot-card not only serves as a record but
also points out the succeeding steps of the operation. This latter is
especially useful for beginners and students. Page 53 shows a desirable
lot-card to be used when making starter. Each operation has been
referred to the page in the text where it is discussed. This makes this
particular lot-card an index to the whole process of starter-making as
here treated.
CHAPTER V
_CURD-MAKING_
Aside from the purely sour-milk cheeses, the coagulum or curd resulting
from rennet action is the basis of cheese-making. The finished cheese,
whatever its final condition, is primarily dependent on a particular
chemical composition and fairly definite physical characters in the
freshly made curd mass. These characters are determined by a series of
factors under control of the cheese-maker. Assuming the milk to be
normal in character, success depends on the use of a proper combination
of these factors. The possible variations in each factor together with
their number makes an almost infinite series of such combinations
possible. The essential steps in the process are, therefore, presented
as underlying all cheese-making. The special adaptations of each factor
are considered in the discussion of the varieties group by group.
These factors follow:
_A._ The coagulation group:
1. Fat-content of the milk.
2. The acidity of the milk.
3. The temperature of renneting.
4. The effective quantity of rennet.
5. Curdling period or the time allowed for rennet action.
_B._ The handling group:
6. Cutting or breaking the curd.
7. Heating (cooking) or not heating.
8. Draining (including pressing, grinding and putting into hoops
or forms).
+77. The composition of the milk.+--The fat percentage in the milk in
the cheese-vat should be known to the cheese-maker and be strictly under
his control. The fat tester and the separator make this clearly
possible. He can go further. Milk from particular herds whose quality is
a matter of record from the routine test of each patron's milk may be
selected and brought together for the manufacturer of cheese of special
quality. Control of casein or lactose, on the contrary, is not nearly so
practicable. The purchase of milk on the fat test has become so well
established in most dairy territories, as to insure the presence and
constant use of the tester. A fat test of the mixed product in the
cheese-vat in connection with established tables thus insures an
accurate knowledge of the materials which go into each day's cheese. For
some varieties of cheese, whole milk should always be used. For other
varieties, the addition or removal of fat is regularly recognized as
part of the making process. The presence of added fat or the removal of
fat affects the texture of the product and the details of the process of
making.
+78. Cheese color.+--An alkaline solution of annatto is usually used as
a cheese color. This colors both casein and fat in contrast to butter
color which is an oil solution of the dye and mixes only with the fat.
Cheese color is added to the milk in making some varieties of cheese,
and not for others. When lactic starter is used, the color should be
added after the starter and just before the addition of the rennet. The
amount is determined by the color desired in the cheese. The usual
amount varies from one to four ounces to each thousand pounds of milk.
Before adding, the color should be diluted in either milk or water,
preferably water. It should then be mixed thoroughly with the milk.
+79. The acidity factor.+--Milk as drawn shows a measurable acidity when
titrated to phenolphthalein with normal sodium hydroxide. This figure
varies with the composition of milk. Casein itself gives a weakly acid
reaction with this indicator. Calculated as lactic acid, this initial
acidity varies within fairly wide limits, records being found from 0.12
to 0.21 of one per cent or even more widely apart. Commonly, however,
such titration shows 0.14 to 0.17 per cent. Some forms of cheese
(Limburger, Swiss, Brie) are made from absolutely fresh milk. Acidity
from bacterial activity is important as a factor in the making of most
types of cheese and probably in the ripening of all types.
Increasing the acidity of the milk hastens rennet action and within
limits produces increased firmness of the curd. If carried too high,
acidity causes a grainy or sandy curd. Normally fresh milk is
sufficiently acid in reaction when tested to phenolphthalein to permit
rennet to act, but the rate of action increases rapidly with the
development of acid. Increase of acidity may be accomplished: (_a_) by
the addition of acid as has been done by Sammis[25] and Bruhn in
pasteurized milk for Cheddar cheese; or (_b_) by the development of acid
through the activity of lactic organisms, which is the usual way. For
renneting, the acidity necessary for particular cheeses runs from that
of absolutely fresh milk still warm (as in French Brie, Limburger,
Swiss, Gorgonzola) through series calling for increase of acidity,
hundredth by hundredth per cent calculated as lactic acid. This ranges
from 0.17 to 0.20 per cent as is variously used in American factory
Cheddar to about 0.25 to 0.28 per cent as obtained by adding acid in
Sammis' method. This method is discussed under the heading "Cheddar
Cheese from Pasteurized Milk" (p. 229) since it requires special
apparatus and has not thus far been used with other types of cheese. For
the development of acidity by the action of bacteria, lactic starter is
almost universally used. This may be added in very small quantities and
the acidity secured by closely watching its development or by adding
starter in amount sufficient to obtain the required acidity at once. In
either case, the cheese-maker needs to know the rate of action of the
culture to insure the proper control of the process. The amount of acid
already present when the rennet is added affects not only the texture of
the curd as first found, but within limits indicates also the rate at
which further acidity may be expected to develop.
A series of experiments in making Roquefort were tabulated to show the
rate of acidification from various initial points. In the graphs (Fig.
8) the curves for acid development are parallel after the determination
reaches 0.30 per cent. These experiments were made at a temperature 80°
to 84° F. Milk at the lowest acidities tried developed titratable acid
very slowly. A period of several hours was required to produce
sufficient acid to affect the curd texture. When the acid reached 0.25
per cent by titration, the further rise was rapid and all the lines
became almost straight and parallel after the titration reached 0.30
per cent. If this rapid souring occurred after the completion of the
cheese-making process, the texture of the experimental cheese was not
measurably affected. In those cases, however, in which 0.30 per cent was
reached before the cheese reached its final form in the hoop, the
texture of the ripened cheese was entirely different from that desired
for this variety under experiment. These curves apply directly to but
one cheese process in which a particular combination of acidity, rennet
and time is used to obtain a very delicately balanced result. In other
varieties it is equally important to obtain exactly the adjustment of
these factors which will bring the desired result.
[Illustration: FIG. 8.--The acidification of Roquefort cheese.]
+80. Acidity of milk when received.+--If proper care has been taken,
milk should be delivered to the factory fresh, clean and without the
development of acid. If the milk has not been handled properly, the
early stages of souring or some other unfavorable fermentation will have
developed. Such milk may develop too much acid, or gas, or any one of
several objectionable flavors during the making and ripening of the
cheese. Some cheese-makers become very expert in detecting the first
traces of objectionable qualities, but most makers are dependent on
standardized tests to determine whether milk shall be accepted or
rejected, and when accepted to determine the rate at which it may be
expected to respond during the cheese-making process.
Various tests have been devised to determine the amount of acid present
in milk. There are two tests commonly used in cheese-factories. One is
known as the "acid test" and the other the "rennet test."
+81. The acid test+[26] is made by titrating a known amount of milk
(Fig. 9) against an alkali solution of known strength, using
phenolphthalein as an indicator. The object of the indicator is to tell
the condition of the milk, whether it is acid, alkaline or neutral. The
indicator does not change in an acid solution but turns pink when the
solution is or becomes alkaline. To make the test, a known quantity of
the material to be tested is placed in a white cup, and to this several
drops of indicator are added. As an indicator, a 1 per cent solution of
phenolphthalein in 95 per cent alcohol is commonly used. As an alkali
solution, sodium hydroxide (NaOH) is used in the standardized strength
usually either tenth (N/10) normal or twentieth (N/20) normal. This
solution should be obtained in some one of the standardized forms
commercially prepared. The alkali is added, drop by drop, from a
graduated burette until a faint pink color appears. This shows that the
acid in the milk has been neutralized by the alkali. The amount of
alkali that has been used can be determined from the burette. Knowing
the amount of milk and alkali solution used, it is easy to calculate the
amount of acid in the substance tested. The results are usually
expressed either as percentages of lactic acid or preferably as cubic
centimeters of normal alkali required to neutralize 100 or 1000 c.c. of
milk. This kind of test is on the market under different names, such as
Mann's, Publow's, Farrington's and Marschall's.
[Illustration: _FIG. 9._--An acid tester.]
+82. Rennet tests.+--Several rennet tests have been devised, but the one
most widely used is the Marschall (Fig. 10). This consists of a 1 c.c.
pipette to measure the rennet extract, a small bottle in which to dilute
the extract, a special cup to hold the milk and a spatula to mix the
milk with the rennet extract. This cup has on the inside from top to
bottom a scale graduated from 0 at the top to 10 at the bottom. There is
a hole in the bottom to allow the milk to run out.
[Illustration: FIG. 10.--Marschall rennet test.]
+83. Marschall rennet test.+--To make a Marschall rennet test, 1 c.c. of
rennet extract is measured, with the 1 c.c. pipette, and placed in the
bottle. Care should be exercised to rinse out the pipette. The bottle is
then filled to the mark with cold water. After the milk has been heated
to the setting temperature, 84°-86° F., the cup is filled with milk and
set on the edge of the vat so that the milk running out through the hole
in the bottom of the cup will flow into the vat. Just as the surface of
the milk reaches the 0 mark on the cup, the diluted rennet extract is
added and thoroughly mixed with the milk, using the small spatula to
stir it. The rennet and milk should be mixed until it has run down at
least one-half space on the scale in the cup. As the rennet begins to
coagulate the milk, it runs slower from the hole in the bottom of the
cup, until it finally stops. When it stops, the point on the scale
indicated by the surface of the coagulated milk is noted. The test is
recorded by the number of spaces the surface of the milk lowers from the
time the rennet is added until it is coagulated. This test depends on
three factors: the strength of the rennet extract, the temperature of
the milk, the acidity of the milk. The more acid, the quicker the milk
will coagulate. To measure any one of these factors, the other two must
be constant. The variable factor is the acidity of the milk. This test
will not indicate the percentage of acid in the milk, but is simply a
comparative test to be used from day to day; for example, if the rennet
test to-day shows three spaces, and the operator makes that milk into
cheese and the process seems to be normal, it shows that for good
results in this factory, milk should be ripened to show three spaces
every day. If the next day the milk showed four spaces, it should be
allowed to ripen more until it shows three spaces. If it shows only two
spaces, this indicates that the milk has too much acid development or is
over-ripe. A cheese-maker will have to determine at what point to set
his milk, because the test will vary from one factory to another.
+84. Comparison of acid and rennet test.+--Each of these tests has its
advantages and disadvantages. The advantage of the acid test is that it
can be made as well of warm as cold milk. This is of great importance in
determining whether the milk delivered by any patron is too ripe to be
received. The acidity of other materials, such as whey and starter, can
be determined as well as that of milk. The disadvantages are that it is
difficult to get the alkali solution of the proper strength and the
solution is liable to deteriorate on standing. It requires a careful
exact operator to make the test.
The advantages of the rennet test are that it is easy to make, and it
requires no materials that are hard to replace. The disadvantage is that
the milk must be warmed to the same temperature before a comparative
test can be made. The size of the outlet in cups varies. It does not
indicate the percentage of acid present in the milk. It is simply a
comparative test. To obtain the best result, both tests should be used
in conjunction.
+85. Control of acid.+--The control of acidity in curd and cheese is
dependent on the control of the moisture or water-content. The control
of both factors is very important in relation to the quality[27] of the
cheese. Often acidity is spoken of when moisture is really intended, and
vice versa. The close relation between the moisture and acidity is due
to the presence of the milk-sugar in solution in the milk-serum which
becomes the whey of cheese-making. Water or moisture in cheese consists
of the remnant of this whey which is not expelled in the making process.
During manufacture and the ripening process, the milk-sugar is changed
to lactic acid. A cheese may be sweet when first made and after a time
become sour because it contains too much moisture in the form of whey.
Excess of whey carries excess of milk-sugar from which fermentation
produces intense acidity.
Various tests have been devised to determine the amount of acid
developed at the different stages of manufacture. These tests are
described on page 61. By the use of such tests, the development of acid
during the manufacturing process can be very accurately determined.
There is no quick, accurate test to determine the amount of moisture in
the curd. The cheese-maker has to rely on his own judgment, guided
largely by the appearance, feeling and condition of the curd.
After the rennet extract has been added, all control of the acid
development is lost. The cheese-maker can determine rather accurately
how fast the acid will develop during the ripening of the milk. This
shows the importance of the proper ripening. The amount of acid
developed during the different stages of the manufacturing process can
be approximately followed with the various acid tests. The manufacturing
process should then be varied to obtain the proper relation between the
moisture and the acid present. The only time that the acidity may be
controlled is when the milk is being ripened. If too much acid is
developed before the rennet is added, there is apt to be too much acid
at each stage of the manufacturing process. This is liable to hurry the
cheese-making process and to cause a loss, both in quality and quantity
of cheese, and may cause a high acid or sour cheese. If sufficient acid
is not developed at the time the rennet is added or if the milk is not
sufficiently ripened, the acid is liable not to develop fast enough so
that there will not be sufficient at each step in the cheese-making
process. Such a cheese is called "sweet." There are several conditions
which will cause an over-development of acid. Such a cheese is called
"acidy" or "sour." These factors are within the control of the
cheese-maker, hence should be avoided. A sour cheese shows lack of skill
and care on the part of the cheese-maker.
_Conditions causing an acidy or sour cheese:_
Receiving sour or high acid milk at the cheese-factory.
Use of too much starter.
Ripening the milk too much before the rennet is added.
Removing the whey before the curd is properly firmed, hence leaving
it with too much moisture.
Development of too much acid in the whey before the whey is removed.
Improper relationship between the moisture and acidity at the time
of removing the whey.
_Conditions causing deficient acid:_
Adding the rennet before sufficient acid has developed.
Not using sufficient starter.
Not developing sufficient acid in the whey.
+86. Acidity and rennet action.+--The rennet extract acts only in an
acid medium. The greater the acid development, within certain limits,
the faster the action of the rennet. If enough acid has developed to
cause a coagulation of the casein, the rennet will not coagulate the
milk. This is one reason why Cheddar cheese cannot be made from sour
milk.
+87. Acidity and expulsion of the whey.+--The contraction of the curd
and expulsion of the whey are so closely related that they may be
treated under the same heading. The more acid, the faster the whey
separates from the curd, other conditions being uniform. The relation of
acidity and firmness of the curd to temperature of the curd is another
important factor in the successful manufacture of cheese. The higher the
acidity, the faster the temperature of the curd can be raised without
any harmful effects. If the temperature is raised too fast in relation
to the acidity, the film surrounding each piece of curd will become
toughened so that the moisture will not be able to escape. When this
condition exists, the curd will feel firm but when the pieces are
broken open the inside is found to be very soft. This results in a large
loss later or may cause a sour cheese. It usually causes an uneven
texture and color in the cheese.
+88. Acidity in relation to cheese flavor.+--Just what part the acid
plays in the development of cheese flavor is not known. If a certain
amount of acid is not present, the characteristic cheese flavor does not
develop. If too much acid is developed, it gives the cheese a sour
flavor which is unpleasant. If sufficient acid is not developed, the
other undesirable factors seem to be more active, causing very
disagreeable flavor and may cause the cheese to putrefy. A cheese with a
low acid usually develops a very mild flavor, and if carried to
extremes, as in the case of some washed curd cheese, the true cheese
flavor never develops.
+89. Acidity in relation to body and texture of cheese.+--If a cheese is
to have a close, smooth, mellow, silky body and texture, a certain
amount of acid development is necessary. If too much acid is developed,
the body and texture will be dry, harsh, sandy, mealy, corky. If the
acid is not sufficient the cheese may be soft or weak bodied, and is
usually characterized by "Swiss curd holes," which are spaces of various
sizes usually more or less round and very shiny on the inside.
+90. Acidity in relation to cheese color.+--An over-development of
acidity affects the color of a cheese. If this development of acidity is
uniform throughout the cheese, it causes the color to become pale or
bleached. If this development is uneven, due to the uneven distribution
of moisture, the color will be bleached in spots, causing a mottled
effect.
+91. Control of moisture.+[28]--The cheese-maker must use skill and
judgment in regulating the amount of moisture in relation to the
firmness of the curd and the acid. Since there are no quick accurate
tests to determine the amount of moisture, this is left entirely to the
judgment of the operator. Certain methods of handling the curd reduce
the moisture-content, while others increase it. The cheese-maker must
decide how to handle the curd. If the curd becomes too dry, methods
should be employed to increase the moisture, and vice versa.
_Causes of excessive moisture:_
Cutting the curd coarse.
Cutting the curd after it has become too hard.
Setting the milk at a high temperature.
Use of excessive amount of rennet extract.
Low acid in the curd at the time of removing the whey.
Not stirring the curd with the hands as the last of the whey is
removed.
High piling of the curd during the cheddaring process.
Piling the curd too quickly after removing the whey.
Use of a small amount of salt.
Holding the curd at too low a temperature after the whey is removed.
Soaking the curd in water previous to salting.
Allowing the curd to remain in the whey too long so that it reabsorbs
the whey.
Heating the curd too rapidly.
_Causes of insufficient moisture:_
Cutting the curd too fine or breaking up the pieces with the rake into
too small pieces.
Cutting the curd too soft.
Stirring the curd too much by hand as the last of the whey is being
removed.
Developing high acid in the curd at the time of removing the whey.
Insufficient piling of the curd during the cheddaring process.
Using a large amount of salt.
High temperature and low humidity in the curing room.
+92. Relation of moisture to manufacture and quality.+--(1) _Flavor:_ If
the cheese contains too much moisture, it is likely to develop a sour or
acidy flavor. A cheese with a normally high moisture-content usually
ripens or develops a cheese flavor much faster than one with a lower
moisture-content, other conditions being uniform. A cheese with a high
moisture-content is much more liable, during the curing process, to
develop undesirable flavors than is one with a lower moisture-content.
(2) _Body and texture:_ A cheese containing too much moisture is very
soft and is difficult to hold in shape. Such a product breaks down very
rapidly and is usually pasty and sticky in texture. If too little
moisture is present, the cheese is very dry and hard, and cures or
ripens very slowly because of the lack of moisture together with
milk-sugar from which acid may be formed. Dry cheeses are usually harsh,
tough and rubbery in texture. Such cheeses also have poor rinds. (3)
_Color:_ If the ideal conditions exist, the moisture will be evenly
distributed throughout the cheese. The spots containing more moisture
will be lighter in color. If a cheese contains so much moisture that it
becomes "acidy," the effect is the same as when too much acid is
developed, that is, the color becomes pale from the action of the acid.
(4) _Finish:_ A cheese containing too much moisture is usually soft. A
good rind does not form. Such a cheese loses its shape very easily,
especially in a warm curing room. (5) _Quality:_ A cheese with a high
moisture-content is usually marketable for only a very short period.
Such a product usually develops flavor very quickly in comparison to a
dry cheese. It must be sold very soon because if held too long, the
flavor becomes so strong as to be undesirable, and objectionable flavors
are liable to develop. In some cases, such cheeses rot.
+93. Relation of moisture to acidity.+--From the preceding discussion,
it is evident that the relation between the moisture and acidity is very
close, in fact so intimate that in some cases it is difficult to
distinguish one from the other when the quality of the cheese is
considered. The proper relation of the moisture and the acidity
determines the quality of the resulting cheese. If too much acid is
developed during the manufacturing process, the product will be sour. If
too much moisture is retained in the form of whey, the cheese will be
sour. The less acid in the curd, the more moisture in the form of whey
may be retained in the curd without causing a sour cheese. The proper
relationship between the moisture and the acidity must be maintained or
a sour cheese will result.
The relation of the moisture to the acidity also has an influence on the
curing. If the cheese has a low development of acidity and a low
moisture-content, it will cure very slowly. The increasing of either the
acidity or moisture usually increases the rate of cheese ripening, other
factors being the same.
The relation of the acidity and the moisture is so important that it
cannot be neglected without injuring both the quality and quantity of
cheese. This knowledge can be obtained only by experience.
+94. Setting temperature.+--The temperature of renneting makes very much
difference in the texture of the product. The enzyme rennin is sensitive
to very slight changes in temperature. Below 70° F., its rate of action
is very slow. Beginning with approximately 20 per cent of its maximum
effectiveness at 70° F. (the curdling point for Neufchâtel), it has
risen to 65 per cent at 84° F., to 70 per cent at 86° F., as used in
Cheddar, to about 80 to 85 per cent at 90-94° F., as used in Limburger.
At 105° F. it reaches its maximum effective working rate to fall from
that efficiency to about 50 per cent at 120° F. Curdling at low
temperature lengthens the time required for the same amount of rennet to
curdle a given quantity of the same milk. The texture of curd produced
at temperatures between 70° F. and 84° F. is soft, jelly-like, friable
rather than rubbery. At 86° F. it begins to show toughening or rubbery
characters which become very marked at 90° F. to 94° F. as used in
Limburger. With the increased vigor of action as it passes its maximum
rate of action at 105° F., the texture tends to become loose, floccose
to granular. Aside from the Neufchâtel group, the working range of
temperatures for the renneting period runs from about 84° F. to about
94° F., a range of barely 10° F., or the use of 65 per cent to 80 or
possibly 85 per cent of the maximum efficiency of the rennet. Within
this range of temperature, the curd has the physical characters demanded
for making most varieties of cheese.
+95. Strength of coagulating materials.+--Rennet and pepsin preparations
vary in strength and in keeping quality. With a particular stock,
changes go on to such a degree that the last samples from a barrel of
rennet are much weaker than the earlier ones. Each sample, barrel, keg
or bottle should be tested before used. In continuous work the results
of each day's work furnish the guide for the next day's use of a
particular lot of rennet.
+96. Amount of coagulating materials to use.+--For most varieties of
cheese, sufficient rennet extract or pepsin is added to the milk to give
a firm curd in twenty-five to forty minutes. Of the ordinary commercial
rennet extract, this requires from two and one-half to four ounces to
one thousand pounds of milk. This gives a maximum of one part rennet for
each four to six thousand parts of milk. The great strength of the
rennet extract is thus clearly shown.
+97. Method of adding rennet.+--Before rennet is added to the milk, it
is diluted in about forty times its volume of cold water, which chills
the enzyme and retards its action until it can be thoroughly mixed with
the milk. If the material is added without such dilution, the
concentrated extract produces instant coagulation in the drops with
which it comes in contact, forming solid masses from which the enzyme
escapes only slowly to diffuse throughout the mass. Uniform coagulation
thus becomes impossible. After the rennet extract has been diluted with
cold water, it should be distributed the entire length of the vat in an
even stream from a pail. It should then be mixed with the milk by
stirring from top to bottom for about three to four minutes. For this
purpose, either a long-handled dipper or a wooden rake may be used. A
dipperful should be drawn from the gate and stirred into the vat,
otherwise the milk in the gate will fail to coagulate properly because
the rennet diffuses too slowly to reach and affect all the milk at that
point. The milk should be stirred on the top, preferably with the bottom
of a dipper, until signs of coagulation begin to appear. This stirring
keeps the cream from rising. There are various ways or signs to indicate
when the coagulation has gone to the stage at which the mix is about to
become thick: (1) The milk becomes lazy or thicker as the finger is
passed through it; (2) bubbles caused by moving the finger remain on the
milk longer, usually until one can count ten when ready to thicken.
If the milk is stirred too long or after it begins to thicken, the
result is a granular sort of curd, and there will be an abnormally large
loss of fat in the manufacturing process. The addition of the rennet and
subsequent stirring require the exercise of great care and constant
attention to details. The cheese-maker can do nothing else for those few
minutes. When through stirring, it is a good plan in cold weather to
cover the vat with a cloth as this will keep the surface of the curd
warm. In summer the same cover will keep out the flies.
_Causes of a delayed coagulation:_
(1) Weak rennet extract or too small an amount.
(2) Low temperatures due to inaccurate thermometers.
(3) Pasteurized milk.
(4) Presence of abnormal bacterial ferments.
(5) Presence of preservatives.
(6) Heavily watered milk.
(7) Use of badly rusted[29] cans.
(8) Milk containing small amounts of casein or calcium salts.
_Causes of uneven coagulation:_
(1) Uneven temperature of the mix in the vat, due to lack of
agitation.
(2) Uneven distribution of the rennet extract.
(3) Adding rennet to vat too soon after heating, while the sides and
bottom are still hot, causes curd to stick to sides and bottom
of the vat making cutting difficult.
(4) Sloshing after the milk begins to thicken breaks the curd and
causes it to whey off.
+98. The curdling period.+--The time allowed for rennet action also
affects the texture of the curd. The enzymes of rennet (rennin and
pepsin) do not cease acting with the thickening of the milk. In many
cheeses, the handling process begins as soon as the curd has become
solid enough to split cleanly before a finger thrust into it. If let
stand further, the same curd mass will continue to harden with the
progressive separation of whey; this shows first as drops ("sweating")
on its surface, which then increase in number and size until they run
together and form a sheet of whey. The limit of such action is difficult
to measure. The solidifying process ceases in a period of hours. The
further action of the enzymes is digestive in character and goes on
slowly. It requires a period of weeks or even months to accomplish
measurable results at the working temperatures in use in the trade.
Other ripening agents with more rapid action intervene to shape the
final result. It follows that the rennet factor in the ripening changes
found at the end of the period is almost negligible for most varieties
of cheese, although it appears to be measurable in some varieties.
+99. Cutting or breaking[30] the curd.+--As soon as curd is formed,
separation of whey begins upon the surface and perhaps around the sides
of the vessel. This is accompanied by shrinkage and hardening of the
mass. If the curd remains unbroken, the separation is extremely slow. In
cheese-making practice, such curd masses may be dipped at once into
hoops as in Camembert, dumped in mass into cloths for drainage as in
Neufchâtel or, as in the larger number of cheeses, cut or broken in some
characteristic manner. After the curd mass is firm, the rate at which
subsequent changes take place depends largely on the size of the
particles into which the curd is cut. The smaller the particles, the
quicker the water is expelled. Consequently the development of the
acidity and other changes take place more slowly. For this reason the
curd should be cut into pieces of uniform size. If the work is not
properly performed, the pieces of curd of various sizes will be at
different stages of development. The fine particles will be firm and
elastic while the larger particles are still soft and full of whey and
may be developing too much acid. The knives should be inserted into the
curd obliquely so that they will cut their way into the curd and not
break it. The horizontal knife is used lengthwise of the vat and cuts
the curd into layers of uniform thickness. The perpendicular knife then
is used lengthwise and crosswise of the vat. It first cuts the curd
into strips and then into cubes. The knives may have wire blades or
steel blades, some operators preferring one and some the other.
Whichever is used, the blades should be close enough together to give
the fineness of curd desired.
After the knife passes through, the cut faces quickly become covered
with a smooth coating, continuous over all exposed areas. This surface
has the appearance of a smooth elastic coating or film. This can be seen
by carefully breaking a piece in the hand. It is this film which holds
the fat within the pieces of curd. If the film is broken, some of the
fat globules are lost because the rennet extract acts only on the casein
and that in turn holds the fat. All the fat globules which come in
contact with the knives as they pass through the curd will be left
between the pieces of curd and will pass off in the whey. If care is
exercised in cutting, the loss of fat will be confined to what may be
called a mechanical loss. This is similar to the loss of the sawdust
when sawing a board. This loss in American Cheddar is about 0.3 per cent
and cannot be avoided. If it is greater than this, it is due to
negligence on the part of the cheese-maker or the poor condition of the
milk. The cutting of the curd into small pieces may be considered a
necessary evil. If the moisture could be expelled from the whole mass
without disturbing it, this fat loss could be prevented. The cutting,
breaking or turning should be done with the greatest care, that the loss
may be as small as possible.
+100. Curd knives.+--For cutting curd, special knives have been devised
(Fig. 11). They consist of series of parallel blades fixed in a frame to
make cuts equidistant. The blades run vertically in one, horizontally
in another. They are spaced according to the demands of the variety of
cheese to be made. Wires stretched in a frame take the place of blades
in some makes of curd knife.
[Illustration: FIG. 11.--Blade and wire curd knives: horizontal,
perpendicular, horizontal, perpendicular.]
+101. Heating or "cooking."+--Curdling by rennet has already been shown
to be markedly hastened by moderate heating. After the coagulum or curd
is formed, the making process may be completed without the application
of further heat, as in Neufchâtel, Camembert and related forms (Fig. 12)
and in some practices with Limburger. In other forms and especially in
the hard cheeses in which cutting of curd is a prominent part of the
process, the curd after being cut is reheated or "cooked." The cooking
process hastens the removal of the whey, thus shortening the time
required to reduce the water-content of the mass to the percentage most
favorable for the type of cheese desired. The process also produces
marked changes in the physical character of the curd mass. With the rise
in temperature the casein becomes elastic first, then approaches a
melting condition and assumes a tough, almost rubbery consistency. The
final texture is the result of the combination of the amount of rennet
added, the temperature, the acidity reached during the process, and the
final water-content of the mass.
[Illustration: FIG. 12.--The heat relation. See pages 77 and 87.]
+102. Draining+ (including grinding, putting into hoops or forms and
pressing).--The reduction of the water in the curd begins almost as soon
as the curd becomes firm. It is aided by cutting or breaking, by the
retention of the heat applied before renneting and by the secondary
heating or cooking used in making certain groups of cheeses. In many
varieties special apparatus is provided in the form of draining boards,
draining racks or bags to hasten the removal of the whey as fast as it
separates. The draining process continues until the cheese has reached
its final form and weight. The intervening process of matting in the
Cheddar group involves a combination of a souring process with the
removal of whey, during which the cubes of curd become fused into
semi-solid masses. If such masses are formed, they must be ground up
before the cheese can be given its final form in the hoop. The draining
process, therefore, may take any one of many forms varying from the
direct transfer of freshly formed curd into hoops in which the entire
draining process is completed, to an elaborate series of operations
which end in pressing curd drained to approximately its final condition
before it is placed in the hoop.
+103. Application to cheese.+--From the discussion of these factors, it
is evident that the cheeses produced will differ widely with the
differences in manipulation. If one considers essential constituent
substances separately, the water-content of the finished product is
found to vary from 30 per cent in Parmesan to 75 per cent in cottage
cheese. The fat-content runs from a trace in some varieties to 60 per
cent in some cream cheeses. The texture of the casein, which gives
character to the product, varies from the tough or glue-like consistency
of freshly made Swiss to the buttery condition of a cream or Neufchâtel
cheese. Inside such limits the tastes of different peoples have led to
the manufacture of many kinds of cheese. Each of these varieties
represents some particular combination of curd-making factors and
ripening conditions which produces a cheese suited to the taste of the
maker and consumer of that country or community.
CHAPTER VI
_CLASSIFICATION_
The literature of cheese-making contains reference to more than 500
names for varieties of cheese. Many of these can be thrown readily into
great groups or families in which there are variations in unessential
detail without modifying the characteristic texture and flavor of the
product. Many varietal names are attached to the product of single
factories or factory groups. Such varieties frequently differ only
slightly in size or shape, or in stage of drainage or of ripening, from
widely known varieties or other similar local forms. The descriptions
recorded for such varieties commonly emphasize minor differences in
manipulation without showing differences in essential factors. Vessels
of particular size are prescribed to be made of wood, earthenware, or of
a special metal. These details specify the exact size and shape of
hoops, the use of particular styles of cutting or breaking instruments
and of certain stirring tools, the material and construction of mats and
draining racks.
The descriptions themselves are very commonly inadequate. The variable
factors in cheese-making are fat-content of the milk, acidity,
temperature of setting, amount of rennet, time allowed for curdling and
the method of draining the curd. The differences in practice lie, with
few exceptions, in the amount or intensity of particular factors, not
differences in kind or quality of treatment. Such contrasts are
quantitative, not qualitative. A great number of combinations is
possible by small variations of these factors.
Varieties selected as types of groups give marked contrasts in
character, but comparison of large numbers of forms shows that almost
every gradation from group to group can actually be found. Within groups
frequently the same physical results in texture and flavor can be
obtained by combinations or adjustments of factors for the purpose of
offsetting or counteracting the effects of one change in practice by the
manipulation of other factors. In ripening, an equally large range of
practices makes possible the development of very different qualities in
mature cheeses from the same lot.
Only a few of the large number of described varieties have obtained even
national importance; fewer still are known outside the country of
origin. In spite of the success of special products when properly
advertised, the largest place in the market is clearly accorded to the
standard forms which are widely known.
+104. Basis of classification.+--A series of these widely known forms
has been chosen as typical of groups in a system of classification
adapted from the French of Pouriau. No completely satisfactory scheme of
classifying all of these varieties has been devised. The grouping
proposed here is based on the principles of curd-making already
discussed together with consideration of the ripening processes to be
discussed with each group. The factors that actually influence the
quality of the final product are separated as completely as possible
from non-essential operative details.
The common use of the terms "soft" and "hard" cheese is based on the
single arbitrary fact of texture. The term "semi-hard" cheese may be
conveniently applied to a miscellaneous group of unrelated families
which are intermediate in texture between such soft forms as Neufchâtel
or Camembert and really hard cheeses like Cheddar or Parmesan. Although
these terms are not made the main basis of the proposed grouping, their
application to sections is indicated. Classification based on the
essential facts of manufacture is, however, really helpful.
ANALYTICAL TABULATION OF GROUPS
Section I. Cheeses with sour milk flavor only (Eaten fresh).
(Soft cheeses 45 to 75% water) PAGE
1. Curdled by souring, Cottage cheese and its
allies in America, many related varieties
in Europe 90
2. Curdled by souring and rennet--the Neufchâtel group 95
a. Skim--Skim-milk Neufchâtel 105
b. Part skim to whole milk--American or
Domestic Neufchâtel 106
c. With fat added--the cream cheeses of
the Neufchâtel group (both American
and European)--such as Cream, Gervais,
Malakoffs, etc. 108
Section II. Cheeses ripened.
Subsection A. Soft cheeses (40 to 50% water).
1. Curdled by souring, heated, then ripened.
Hand cheese, Pennsylvania pot cheese,
Harz, etc. 112
2. Curdling by souring and rennet, ripened
Ripened (French) Neufchâtel 114
3. Curdled primarily by rennet.
a. Ripened by mold--Camembert, Brie
and their allies 117
b. Ripened by bacteria.
* Made from soft or friable
curd--d'Isigny, Liederkranz, etc. 134
** Made from firm or tough
curds--Limburger and allies 139
Subsection B. Semi-hard cheeses, firm, well-drained
(38 to 45% water)
a. Curd not cooked, ripened by molds.
* Made from friable curd--Roquefort 150
** Made from firm or tough
curd--Gorgonzola, Stilton and
such French forms as Gex,
Septmoncel 158
b. Curd cooked and ripened by
bacteria,--brick, Munster, Port
du Salut (Oka) 164
Subsection C. Hard cheeses, cooked and pressed (30 to
40% water).
a. Ripened without gas holes.
1. Dutch--Edam, Gouda 173
2. Danish.
3. The Cheddar group.
* English--Cheddar and numerous
related forms known principally
in Great Britain 184
** American--the factory Cheddar of
United States and Canada 184
b. Ripened with the development of
gas holes.
* Holes large--Swiss-Emmenthal,
Gruyère, American Swiss 276
** Holes small--Parmesan and related
varieties 288
Such a classification brings together series of products in which there
is essential similarity in the final output, however great the
differences in manipulation. It does not consider all varieties and
specialties. Some of these groups are important enough to demand special
mention.
+105. Processed cheeses.+--Cheese of any group may be run through mixing
and molding machines and repackaged in very different form from that
characteristic of the variety. In such treatment, the texture and
appearance may be so changed as to give the effect of a new product.
Substances (such as pimiento) are added to change the flavor. Or the
product may be canned and sterilized with equally great change of
flavor and texture. One thus finds Club made from Cheddar; Pimiento
from Cream, Neufchâtel or Cheddar; similarly olive, nut and other
combinations are made. The possible variations are numerous.
+106. Whey cheeses.+--Several products bearing cheese names are made
from whey. These take the forms of the recovery of the albumin and
casein separately or in a single product, and the recovery of the
milk-sugar either alone or with the albumin. Whey cheeses have been
especially developed by the Scandinavian people, although some of them
have their origin in the south of Europe. Certain of these varieties are
produced on a limited scale in America.
There are a number of forms fairly widely known that are difficult to
place in this scheme of groups. Among these are Caciocavallo, Sap Sago.
+107. Soft and hard cheeses.+--Another commonly used classification
makes two groups: (1) soft cheeses; (2) hard cheeses. In such a
classification the semi-hard group presented here is included with the
soft cheeses. Some cheeses of this group are soft in texture. This is
correlated with high water-content, high fat-content or both together.
+108. Relation of moisture to classes.+--In this classification the
water-content reflected in the texture of the cheese assumes first
place. To carry the analysis somewhat further by showing the correlation
between water-content and certain factors, a tabulation of well-known
varieties of typical groups is presented (Table III). In this table the
series of typical dairy products are first arranged according to
water-content of the final product. Approximate limits of percentages of
milk-fat are also given, because milk-fat frequently affects texture to
a degree almost equal to water. Column 4 gives the period within which
the more quickly perishable cheeses are usable, and the length of the
ripening for the more solid forms. The correlation between
water-content, texture and the time of keeping is clearly shown for most
varieties.
TABLE III
CORRELATION WATER- AND FAT-CONTENT WITH RIPENING
------------------+--------+--------+-------------+--------------
| PER | PER | |
VARITY OF | CENT | CENT | PERIOD | RIPENING
| WATER | FAT | REQUIRED | AGENT
------------------+--------+--------+-------------+--------------
Cheese: Soft, | | | |
Cottage | 70 | trace | a few days | Bacteria
Skim Neufchâtel | 70 | trace | a few days | Bacteria
Neufchâtel | 50-60 | 12-28 | a few days | Bacteria
Camembert | 50 | 22-30 | 3-5 weeks | Molds
Cream cheese | 40-50 | 35-45 | a few days | Primarily
| | | | bacteria
| | | |
Semi-hard: | | | |
Limburger | 40-45 | 24-30 | 3-6 months | Bacteria
Roquefort | 38-40 | 31-34 | 3-6 months | Mold
Brick | 37-42 | 31-35 | 3-6 months | Bacteria
| | | |
Hard: | | | |
Cheddar | 30-39 | 32-36 | 6-12 months | Bacteria
Swiss | 31-34 | 28-31 | 9-18 months | Bacteria
| | | | and yeasts
Parmesan | 30-33 | | 2-3 years | Bacteria
------------------+--------+--------+-------------+--------------
The soft cheeses are quickly perishable products. Bacteria and molds
find favorable conditions for growth in products with 45 to 75 per cent
of water. If such growth is permitted, enzymic activities follow quickly
with resultant changes in appearance, texture, odor and taste.
Refrigeration is necessary to transport such cheeses to the consumer,
if properly ripened. Trade in these forms may continue throughout the
year in cool climates and in places where adequate refrigeration is
available. Practically, however, outside the large cities this trade in
America is at present limited to the cold months; inside the large
cities much reduced quantities of these cheeses continue to be handled
through the year.
In the stricter sense, the soft group of cheeses falls naturally into
two series: (1) the varieties eaten fresh; and (2) the ripened soft
cheeses. Those eaten fresh have a making process which commonly involves
the development of a lactic acid flavor by souring, but no ripening is
contemplated after the product leaves the maker's hands. In the ripened
series, after the making process is completed, the essential flavors and
textures are developed by the activity of micro-organisms during
ripening periods varying in length but fairly well-defined for each
variety.
In contrast to the soft cheeses, the hard kinds are low in
water-content, ripen more slowly and may be kept through much longer
periods. They retain their form through a wider range of climatic
conditions. They develop flavor slowly and correspondingly deteriorate
much more slowly. Such cheeses are in marketable condition over longer
periods. In their manufacture the cooking of the curd takes a prominent
place.
+109. Relation of heat to classes.+--The close relation between the heat
applied and the product sought forms the basis of a striking series of
graphs (Fig. 12, page 78). These show the changes hour by hour in the
heat relation during the making process of a series of widely known
forms, each of which is chosen as typical. In some of these forms, heat
is applied but once to bring the milk to the renneting temperature
typical for the variety. Subsequent manipulations are accompanied by a
steady fall in temperature. In other forms, the curd when solid is
specially heated or "cooked" to bring about the changes characteristic
of the variety. These contrasts are clearly brought out by the graphs
which represent practices well recognized for the varieties. The
detailed process for these groups is considered in succeeding chapters.
CHAPTER VII
CHEESES WITH SOUR-MILK FLAVOR
The cheeses with flavor of sour milk are probably more widely used than
any other group. Historically and to a very large degree at present,
they are farm cheeses.[31] No estimate of volume of such production in
the household has ever been made. The utilization of surplus milk in
this way is of ancient origin.
With the introduction of the factory system of handling milk, the
manufacture of such cheese in the household was largely dropped. The
rise in price of all food substances and increasing appreciation of the
food value of milk products have made the recovery of all surplus milk
in some form very necessary. The manufacture of cottage, Neufchâtel and
cream cheese is one of the best forms of such recovery which may be
adapted to utilize any grade from skimmed-milk to cream. Large
quantities of skimmed-milk have frequently been lost from the total of
human food by the manufacture of casein for industrial uses, and by use
as stock feed.
+110. Skim series.+--The kinds of cheeses eaten fresh have in common a
very soft texture and the flavor of sour milk, principally lactic acid.
The group falls naturally into two sections: (1) the cheeses made from
milk curdled by souring; (2) those for which the milk is curdled by
souring and rennet. In the latter group both agencies are necessary to
the resulting product. The time required to curdle by souring alone is
longer than when rennet is used; this period is usually longer than
necessary for the cream to rise by gravity; hence the cream is either
skimmed off or removed with the separator beforehand. The curd,
therefore, is essentially a skimmed-milk curd. Casein curdled in this
way tends to become granular or "rough," to feel "sandy" when rubbed
between the fingers. Heating is commonly necessary to lower the
water-content of the mass even to 75 per cent. Such curd tends to become
hard or rubbery when heat is applied. In this group, the best known form
is variously called "cottage" cheese, "clabber" cheese, schmierkäse.
+111. Cottage cheese+ is made from skimmed-milk, soured by lactic
bacteria until a curd is formed. This is done preferably at about 20° C.
(70° F.), because at this temperature the purely lactic type of organism
has been found to outgrow competing forms which may be present. Starter
containing the desired culture, if properly used, saves much time in the
curdling period. Such curdling requires at least twelve to twenty-four
hours, frequently much longer unless abundant starter is introduced.
+112. Household practice.+--The details of cottage cheese making in the
home differ widely in separate sections and even in different families
in the same part of the country. The essentials of the practice, common
to all, include: (1) curdling the whole milk by natural souring; (2)
removing the sour cream which is usually used for butter-making; (3)
scalding the curdled skimmed-milk either by slowly heating it in the
original vessel surrounded by hot water or by actually pouring an
approximately equal volume of boiling water into the curdled mass; (4)
bagging and draining the mass until it reaches the desired texture; (5)
the kneading of the mass with the addition of salt and cream. The
resulting product varies greatly in quality. Unfavorable fermentations
frequently affect the flavor.[32] The "scalding" varies from a
temperature of 90° F. almost to boiling with a resultant texture varying
from almost the smooth buttery consistency of Neufchâtel to hard coarse
granular lumps. The best practice, using clean well-cared-for milk and
draining at low temperature, produces a very attractive cheese. Such
cheese is heated to 90° to 100° F. on the maker's judgment, drained
carefully, kneaded well by hand or by machine with the addition of cream
to give it an attractive texture and flavor.
+113. Factory practice.+--When cottage cheese is made in the
factory,[33] separated milk is taken; it should be pasteurized and then
soured by a lactic starter. The souring can be accelerated by the use of
a starter, which may be added at the rate of 0.5 to 5 per cent of the
skimmed-milk used, depending on the amount of starter that can be made.
Generally, the more starter added, the more rapid will be the
coagulation and the better will be the flavor of the cheese. As soon as
the milk has thickened, the curd is ready to be broken up and separated
from the whey. This separation is hastened by the application of heat.
Usually the temperature of the curd is raised slightly before it is
broken up; since this makes the curd firmer, there will be a smaller
loss of curd particles in the whey. The curd may be cut with coarse
Cheddar cheese knives or broken with a rake. The temperature of the curd
should be raised very slowly, at least thirty minutes being taken to
reach the desired final temperature. No set rule can be given as to the
exact temperature to which the curd should be heated. The temperature
should be raised until a point is reached at which the curd, when
pressed between the thumb and the fingers, will stick together and not
go back to the milky state. This temperature is usually from 94° to 100°
F., but the cheese-maker must use his own judgment in this respect. If
the curd is heated too much, it will be hard and dry; on the other hand,
if it is not heated sufficiently, the whey will not separate from the
curd and the latter will be very soft and mushy.
When the curd has been heated sufficiently and has become firmed in the
whey, it should be removed from the whey. This may be done either by
letting down one end of the vat and piling the curd in the upper end, or
by dipping out the curd into a cloth bag and allowing the whey to drain,
which it does very rapidly. No treatment can prevent the "roughness" of
an acid curd (this is a fine gritty feeling when rubbed between the
fingers), but the coarse hard grainy texture and lumps characteristic of
the highly heated curd do not develop. Experimental workers have agreed
that to have the proper texture, such curd should contain when finished
about 70 to 75 per cent of water. It should have a mild but clean acid
flavor. Such a cheese will carry about 1 to 2 per cent of salt, without
an objectionably salty taste. This cheese is commonly sold by measure,
sometimes in molds or cartons. The manufacture of all forms of cottage
cheese has been largely superseded by the making of skimmed-milk
Neufchâtel or Baker's cheese.
The yield from one hundred pounds of skimmed-milk runs up to fourteen to
nineteen pounds of cheese, when made very wet or from pasteurized milk.
The yield varies with the moisture-content of the cheese, being greater
for cheese with a high content. Too much moisture or whey should not be
left in the curd, however, as this will render it too soft to be
handled.
Cottage cheese made by either the home or factory practice is a quickly
perishable article. Although the acid restrains bacteria at first, the
high percentage of water favors the growth of molds which tolerate
acidity, especially _Oidium (Oospora) lactis_ and the Mucors or black
molds. These molds destroy acidity rapidly and thus permit the bacteria
of decay to develop and to produce objectionable taste and odors.
Spoilage in these products is accelerated by the kneading process which
distributes air throughout the mass and with it all forms of microbial
contamination.
+114. Buttermilk cheese.+--A cheese closely resembling cottage may be
made from buttermilk. If the buttermilk came from cream which was
churned before it became sour, the process is the same as that already
described for the making of cottage cheese from skimmed-milk. If the
buttermilk came from sour cream the process of manufacture is much more
difficult. The casein of sour cream has already been coagulated with
acid and broken during churning into very minute rather hard particles.
These fine particles are difficult to recover. They are so fine that
they pass through the draining cloth or at other times clog it and
prevent drainage. They do not stick together at ordinary temperatures.
They cannot be collected by the use of acid because they have already
been coagulated with acid. After casein has been coagulated with acid,
rennet extract will not recoagulate the particles. The buttermilk may be
mixed with sweet skimmed-milk; then as the latter coagulates, it locks
in the casein of the buttermilk so that it can be collected. If
buttermilk from soured cream is used alone, the casein may be
collected[34] by neutralizing and heating to 130 to 150° F., and holding
until the casein gathers together. The whey can then be drawn off. Often
there is further difficulty in getting the casein to collect, since the
pieces remain so small that they go through the strainer.
Cheese made entirely from buttermilk is sandy in texture and often not
palatable. If the buttermilk with good flavor is mixed with
skimmed-milk, it makes a good cheese closely resembling cottage.
+115. Neufchâtel group.+[35]--The Neufchâtel process originated in
northern France where a number of varieties are included under this as a
group name. Among these are Bondon, Malakoff, Petit Suisse, Petit Carré.
The name designates a general process of curd-making which is applied to
skimmed-milk, whole milk or cream. Some of the resultant cheeses are
ripened; some are eaten fresh. The Neufchâtel cheeses of France gained
such wide recognition for quality that the process of making has become
widely known. In America the manipulations of the French process were
early dropped. The essentials were made the basis of a successful
factory practice which has been widely adopted. The American factory
practice is discussed here and the French process briefly considered
under the heading Ripened Neufchâtel. (See Chapter VIII.)
+116. Domestic or American Neufchâtel cheeses+ are soft, have clean sour
milk (lactic acid) flavor and are quickly perishable. In all but the
coldest weather, they require refrigeration to reduce deterioration and
loss. They range in fat-content from traces only to 50 per cent and
more; in water from 40 to 75 per cent, according to the milk used. In
texture Neufchâtel is smooth, free from gas, free from lumps or
roughness when rubbed between the fingers. This flavor and texture is
obtained by a combination of slow rennet curdling with developing
acidity. No further ripening is permitted.
+117. The factory.+--Neufchâtel factories require the standard dairy
equipment for receiving, weighing, testing, separating, heating,
pasteurizing and cooling the milk. Since many factories produce several
products, the same general dairy equipment may serve for all. In
addition to such equipment, Neufchâtel requires a curdling apparatus
which can be held at 70-75° F. This may be a room properly controlled,
or a tank where temperature control is obtained by water and steam. For
draining, a room kept at 60° F. gives nearly the ideal temperature,
which must be supplemented by relative humidity high enough to prevent
the exposed surface of curd from drying during periods of twelve to
twenty-four hours. This requires almost a saturated atmosphere. A room
with special molding machinery is required and tables for wrapping,
labeling and boxing the product are necessary. Box-making machinery is
usually an economic necessity for work on a large scale. Adequate
refrigeration is requisite both to chill the curd before molding and to
preserve it after packaging.
[Illustration: FIG. 13.--Neufchâtel draining racks.]
+118. Cans.+--For curdling, the "shot-gun" can, about nine inches in
diameter and twenty inches deep, is generally used. This holds thirty to
forty pounds of milk. Increased capacity is dependent, therefore, on the
number of units installed, not on changes in the units themselves.
[Illustration: FIG. 14.--Detail of a Neufchâtel draining rack.]
+119. Draining racks.+--A draining rack is required for each can of
curd. These racks also are standardized units whose number limits the
capacity of the factory. The design of these racks (Figs. 13, 14) and
their arrangement in the draining room are taken from Bulletin 78 of the
Storrs Agricultural Experiment Station: "The racks are rectangular,
thirteen inches wide, thirty-six inches long and ten inches deep. The
corner posts extend one and one-half inches beyond the strips at top and
bottom with the tops rounded as a rule as seen in the photograph. The
bottom slats fit loosely into notches, hence are removable for washing
purposes. The materials required are four corner posts one and one-half
by one and one-half inches; nine strips one by three-eighths by
thirty-six inches; six strips one by three-eighths by thirteen inches,
two strips one by three-eighths by twelve and a quarter inches, notched
to receive the bottom slats; all made from pine."
+120. Cloths.+--For each draining rack, a cloth one yard wide and one
and one-half yards long is required. Cotton sheeting is satisfactory for
the purpose; "even-count, round-thread, unmercerized voile" is suggested
by Dahlberg.[36]
[Illustration: FIG. 15.--Neufchâtel and cream cheese molds.]
+121. Molding machinery.+--For work on a large scale, special power
machines[37] are regularly used. These consist of a hopper and worm
delivering a standard size stream of curd through a proper size and
shape of delivery tube. This curd stream is cut by an automatic device
into the proper lengths to form the standard cheese. In this way a
uniform size of cheeses is obtained. Experimental work with hand
apparatus showed that a worm six inches in diameter is required to
deliver curd in a smooth column one and one-half inches square. If the
pressure is not sufficient, the column will frill at the edges. Such
irregular surfaces cannot be wrapped smoothly enough to delay spoilage.
On a small scale, a fair grade of product can be molded through a tin
tube (see Fig. 15) one and three-quarters inches in diameter and ten
inches long in which the curd is compressed by a close fitting plunger
operated by hand.
+122. Milk for Neufchâtel+ should be clean, free from gas and taint.
Such milk should preferably be not more than twelve hours old when
received and in no case show higher than 0.20 per cent lactic acid by
titration. Milk testing 4 per cent fat or higher will produce a higher
quality of product than lower grade milk, although every grade from
skimmed-milk to cream is used in producing some form of Neufchâtel. This
milk should be pasteurized unless shown to be free from tuberculosis by
proper test of the cattle. Evidence[38] that the organism of
tuberculosis will withstand the regular handling process for cheeses of
this group and retain its ability to cause disease in experimental
animals makes the introduction of pasteurization necessary in this whole
group of cheeses. Any effective pasteurization may be used, but
temperatures of 140-145° F. for thirty minutes have been effective with
less changes in the milk than higher temperatures for shorter periods.
The milk should be cooled to curdling temperature and the starter and
rennet added and stirred into the milk in bulk. The milk may then be
quickly distributed into the curdling cans with a hose or from the gate
valve of the mixing vat.
+123. Starter.+--To insure the development of a clean acid flavor, a
small amount of lactic starter should be used. The quantity to use
depends on the quality of the milk. With skimmed-milk, a pint for each
thirty-pound can is recommended by Matheson and Cammack[39] and by
Dahlberg. (See page 98.) For whole-milk Neufchâtel, 2 c.c. to a
thirty-pound can of milk commonly gives good results. On this basis 2
ounces of starter would be sufficient if properly stirred into about
1000 pounds of milk. Too slow development of acid is preferable to
over-rapid souring.
+124. Renneting or setting.+--The milk should be cooled after
pasteurizing to between 70° and 75° F. Rennet is added at the rate of
1/3 c.c. to a thirty-pound can (roughly 1/3 ounce to 1000 pounds). This
will thicken the milk sufficiently in the first few hours to reduce the
separation of the cream. For completion of the curdling and souring
process, twelve to eighteen hours are required. Usually the cans stand
overnight at uniform temperature. When ready to drain, the curd should
be firm, smooth and mildly acid. Whey separating from it should not
titrate above 0.35 per cent titrated as lactic acid.
+125. Draining.+--A cloth is spread over a draining rack and the
contents of one "shot-gun" can poured upon the cloth with as little
breaking as possible. In this way a large surface is exposed. The room
must be kept wet to prevent the surface of the curd drying to form
crusts which stop draining. A temperature of 60° F. is favorable to the
maintenance of proper texture and humidity without the development of
objectionable organisms, especially _Oidium lactis_, which tends to
cover every exposed surface in such rooms. Draining may be hastened by
turning the curd or changing the position of the cloth. In factory
practice, the large draining surface reduces the necessity of handling
the curd and reduces the loss of fat. About twelve hours are required
upon the draining racks.
On a small scale with a few cans of curd in the home, any form of
draining rack may be used, such as a potato or berry crate, or the
corners of the cloth may be brought together, tied and the mass hung up.
The curd must be turned by pulling up the corners of the cloth to
prevent drying at the edges and stoppage of draining from the center of
the mass. Such treatment produces much more rapid drainage than the
factory practice and involves proportionately more labor and larger fat
losses.
+126. Cooling Neufchâtel.+--When whey ceases to separate readily, the
corners of the cloth are loosed from the rack, folded diagonally or
tied, and the curd cooled on ice or in refrigerators. When thoroughly
chilled the bags of curd are put into presses, where light but
increasing pressure forces more whey out of the mass. Tests at this time
should show about 0.60 per cent acid in the whey. With low-fat curd
every step of the process may be hastened, but with high-fat care must
be exercised to prevent loss of fat during pressing especially. Any
pressing device permitting continuous pressure with ease of manipulation
may be used.
+127. Pressing.+--The ideals of the maker must determine the extent of
pressing. A high yield is obtained by leaving whey in the curd. If
immediate consumption is certain, such cheese may be satisfactory, but
if the cheese is to be held some days the extra whey carrying more
milk-sugar favors increased acid development. This produces very sour
cheese with much more danger of other fermentations which cause
objectionable flavor. Too much water favors more active bacterial growth
as well as produces cheese too soft for the necessary handling in the
market.
In the press, several bags of curd may be piled together. The press
should be released and the bags turned from time to time to insure even
drainage. Several hours of pressing are usually required. The danger of
insufficient pressing is due to the difference of texture between the
worked and unworked curd. Before working, curd carrying 10 per cent
excess moisture resembles the finished product sufficiently to deceive
any but the experienced maker. But if this curd is transferred to the
worker and to the molding machine, it is found to become soft, pasty and
sticky, to lack "body," hence to make very unsatisfactory packages and
to spoil very quickly. The masses of curd should come out of the press
as dry and hard flat cakes.
[Illustration: FIG. 16.--Working Neufchâtel.]
+128. Working and salting Neufchâtel.+--The cakes of curd go from the
press to the working table. Here they are broken by hand or by a
butter-worker or kneading machine (Fig. 16). Salt at the rate of one
and one-half pounds to 100 pounds of curd is added. If the curd is not
sufficiently pressed, the masses become mushy or pasty during the
working process. The working is continued until the whole mass is
uniformly smooth and buttery.
+129. Storage.+--The draining and working processes permit the
contamination of the curd with organisms from the air and from the
apparatus. These are distributed throughout the mass. Air is also worked
thoroughly into the curd. Such a product spoils quickly. Distributing
houses find the Neufchâtel trade uncertain in volume from day to day,
hence many of them store the cheese in bulk and package only fast enough
to fill orders. This minimizes the loss due to spoilage. Such curd may
be packed into tubs and kept for considerable time in cold storage. If
molded for the retail trade, it is more quickly perishable. When packed
solidly in mass, curd is largely protected from spoilage by the
exclusion of air and perhaps the quick exhaustion of free oxygen through
the respiration of the micro-organisms present and by its acidity. This
must be supplemented by low temperature to reduce the loss to a minimum.
Even when spoilage begins, it is easily confined to the slight growth of
_Oidium lactis_ or green mold and bacteria on exposed areas. These can
be removed with minimum loss and damage to the mass. On the other hand,
such curd molded into the commercial package of 3 to 6 ounces and
wrapped in paper, with tin-foil or carton for protection, still presents
enormously increased surface for the growth of aerobic forms--especially
_Oidium lactis_, green mold (Roquefort mold is the usual green species)
and accompanying bacteria. Curd in tubs may be kept some days; in
commercial packages lowering of quality (flavor) begins almost at once.
+130. Molding.+--When the standard molding machine (Fig. 17) is
provided, curd is brought directly from the refrigerator to the machine.
If permitted to become warm, the mass becomes sticky; when cold it is
more readily handled. The machine is fitted with the special delivery
tube for the variety to be handled, cylindrical for Neufchâtel in its
various forms, rectangular in section for cream. Enough workers should
be provided to wrap and label the cheese without leaving it exposed to
contamination or heat. Parchment paper and tin-foil cut the proper size
for each variety and bearing printed labels are readily obtainable. Each
cheese should be wrapped with paper and tin-foil and put directly into a
flat box which holds a standard number (usually 12 or 24) of the special
product.
[Illustration: FIG. 17.--Molding Neufchâtel.]
In working with the hand molding tube (Fig. 15) the same care is
required. Chilled curd is forced into a firm smooth mass with the
plunger. It is removed and wrapped when it reaches the regular size of
the variety.
All forms when molded go directly into the boxes and then back to the
refrigerators until demanded for actual use. The details of the process
differ according to the form made.
+131. Skimmed-milk Neufchâtel.+--Separator skimmed-milk is frequently
made into curd by the Neufchâtel process. The absence of fat eliminates
the largest element of loss in manufacture. Each stage of the making
process, therefore, may be shortened. The demand that the curd shall be
smooth and buttery in texture rather than rough or gritty requires the
exercise of care in curdling of milk. The draining and pressing of the
curd may be accomplished much more rapidly than in the fatty cheeses.
The final product should differ from cottage cheese in smoother texture,
milder acidity and, as a rule, cleaner flavor. In composition, the
absence of fat must be largely compensated by leaving more water in the
cheese. Such a product reaches the market with 65 to 75 per cent of
water and perhaps 1.25 per cent of salt. Casein forms 20 to 30 per cent
of the mass.
These cheeses are very perishable on account of their high
water-content. The destructive effect of microorganisms both in the
interior of the cheese and upon its surface is rapid.
Cheeses of this description may be found in the trade as cottage cheese,
Neufchâtel style, and as Neufchâtel made from skimmed-milk; skimmed-milk
Neufchâtel would be a strictly proper labeling.
+132. Baker's cheese.+--There is considerable market for skimmed-milk
curd as Baker's cheese. This product is essentially skimmed-milk
Neufchâtel curd, partially drained and sold in bulk. When the bakery is
near by, the curd is frequently shoveled into milk-cans in very wet
condition and sent directly from the factory to the bakery. If the
distance is such as to require considerable time for transportation,
the same care is frequently given as for Neufchâtel curd packed in bulk
for storage and transportation.
Great variations in practice are found among the makers of this type of
product. In some cases low grade skimmed-milk is handled on a large
scale. Curdling is done quickly and little care is given to the details
of flavor and texture in the curd. Working in this manner, two men are
able to make a ton of such curd, and ship it out in milk-cans each day.
The resulting product, although very deficient in flavor and texture,
goes into manufactured specialties which conceal its deficiencies if
considered as cheese.
+133. Domestic Neufchâtel.+--The name Neufchâtel, unless limited clearly
by the label, should designate a cheese made from fresh whole milk.
Cheeses of this group are produced in a small number of well-equipped
factories scattered widely through the dairy states of the North and
Northeast. Every factory uses one or more trade names for its product.
The same product is frequently relabeled by the distributor who uses his
own trade name instead of that of the maker.
The usual form of package is cylindrical, about 1¾ inches in diameter
and 2½ inches long, or sometimes rectangular 2½ by 1½ by 1½
inches. The cheese is protected by wrapping in parchment paper closely
surrounded by tin-foil. These packages vary from 2½ to 4 ounces. In
some cases screw-topped glass jars are substituted for the tin-foil
package. They are objectionable, first, because of cost and, second,
because they are so commonly associated with less perishable products as
to mislead either dealer or consumer into holding the product for too
long a time. The paper or tin-foil package can be kept only at
refrigerator temperature, hence automatically keeps its possessor
reminded of the perishable nature of its contents.
Neufchâtel of the best quality made from whole milk testing about 4 per
cent fat may be expected to fall within the following limits;[40] many
grades contain more water than this at the expense of flavor and keeping
quality:
Water 50-55 per cent
Fat 23-28 per cent
Casein 18-21 per cent
Salt 0.5-1.25 per cent
Yield 12-14 lb. per 100 lb. of milk.
+134. Partially skim Neufchâtel.+--Brands of Neufchâtel made from milk
that would test every gradation from whole milk to separator
skimmed-milk may be found. The quality of the product varies with the
skill of the maker from brands no better than cottage cheese to products
scarcely distinguishable from the best whole-milk Neufchâtel. Many
factories that produce more than one quality of Neufchâtel use labels of
different color, different design or both to separate them; for example,
blue labels usually stand for whole milk, red labels represent lower
grades. Sometimes the difference in material is indicated by a clear cut
grade mark. Frequently color, a design of label or both are the only
definite marks upon the cheese. The consumer unfamiliar with the trade
practice commonly has no means of knowing the quality of the product
offered. Such cheeses vary in water-content from 55 to 70 per cent; in
fat from 10 to 25 per cent; in casein from 18 to 25 per cent.
+135. Cream cheese.+--The Neufchâtel process is also used to make cream
cheese. The material utilized is commonly what has been called double
cream. This is produced by separating about half of a given volume of
milk and running the cream into the other half. Usually cream cheese is
made in the same factory as various grades of Neufchâtel. No material is
lost. In some instances, cream cheese is prepared by working thick cream
into the Neufchâtel type of curd from practically skimmed-milk. In
working with high percentages of fat in curd, care must be taken to
avoid loss of fat in draining and pressing. The curd is carefully
chilled before pressing to reduce this loss. This may be done under
refrigeration or upon cracked ice. Otherwise the manipulations of the
process are unchanged. The cheeses are commonly molded in the Neufchâtel
machine into square cakes weighing about 4 ounces and measuring
approximately 3 by 2¼ by 7/8 inches. These are wrapped in paper and
tin-foil and handled exactly as Neufchâtel.
Cream cheese of high quality made from reënforced milk testing 7 to 9
per cent fat may be expected to test approximately as follows:[41]
Water 38-43 per cent
Fat 43-48 per cent
Protein 13-16 per cent
Salt 0.5-1.25 per cent
Yield 16-18 lb. per 100 lb. of cream.
Increases of water, hence greater yields, are very common but usually
associated with loss in quality both as to flavor and texture, and in
more rapid spoilage; certain brands regularly carry 50 to 60 per cent of
fat but their increased cost of manufacture and sale restricts them to
the rôle of specialties with closely limited distribution. Trade names
such as Philadelphia Cream, Cow Brand, Eagle Brand, Square Cream, Blue
Label and many other factory brands are on the market.
+136. Neufchâtel specialties.+--Neufchâtel or cream cheese curd is
frequently mixed with some flavoring substance, such as pimiento
(pickled Spanish peppers), olives, nuts, spices or other cheeses, such
as Roquefort. These bear appropriate trade names and form a very
attractive addition to our varieties of cheese. Among the names found
are Pimiento, Olive, Nut, and Pim-olive or Olimento.
+137. Gervais+ is a brand of cream cheese made in Paris and sold widely
in France and even in other continental countries. It occasionally comes
to America. As made in Paris, these cheeses are flat cakes containing
approximately 40 per cent water and 35-45 per cent fat. It clearly
differs only in detail from the square cream cheeses made in America.
The name Gervais is the property of a particular company. Since the
cheese differs in no essential feature from other cream cheeses, this
name should not be applied to a domestic cream brand.
+138. European forms occasionally imported.+--Among the cheeses related
to Neufchâtel as they reach the market are the "White" cheeses of
southern Europe. These differ greatly in quality according to their
source and to their content of cow, sheep, goat's milk or some
combination of these. This texture and flavor link them with unripened
Neufchâtel. The time required for importation puts a minimum possible
period of ten to fifteen days between production and consumption with a
probable period of at least one month for most samples. As they come to
America, these forms usually show fermentive changes beyond those
tolerated in the domestic product. This may take either of several
forms: (1) intensification of acid flavor with the intensification of
the characteristic flavors of the particular brand; (2) the development
of old or rancid flavors; (3) the development of Oidium and partial
softening of the mass through its agency; (4) the growth of Roquefort
mold and development of the flavor associated with that organism. This
last form was found in a shipment of Hungarian Briuse which showed about
40 per cent fat, 14 per cent protein and 43 per cent water.
CHAPTER VIII
_SOFT CHEESES RIPENED BY MOLD_
The ripened soft cheeses include a series of groups of varieties which,
in addition to initial souring, have been subjected to special ripening
processes, and which in the ripened condition are soft in texture and
mostly have high flavors. The varieties in each group have in common
some essential principles of manufacture together with a ripening
process dominated by a characteristic group of organisms. In certain
groups, the ripening is dominated by a yellowish or orange viscid
surface slime containing _Oidium lactis_ and bacteria; in another
series, the characteristic organism is a mold of the genus Penicillium
(_P. Camemberti_). Referring to the analysis of groups (page 83), the
ripened soft cheeses are found to fall into three well-marked groups,
one of which may perhaps be subdivided as indicated. The series curdled
by souring alone begins with approximately cottage cheese curd and
develops high flavors by ripening, as in "hand" cheese. Ripened
Neufchâtel curdled by souring and rennet together finds its basis in
Neufchâtel curd also but modifies the final product until the familiar
flavor and texture of the unripened form are no longer recognizable.
Among the forms curdled by rennet alone the Camembert series contains
one form, Coulommiers, which is occasionally used unripe, but represents
in general a mold-ripened group of highly flavored forms. The series of
soft rennet cheeses ripened by bacteria may be broadly designated the
Limburger group.
+139. Hand cheese and its allies.+--Among skim cheeses, there is a
series of forms largely German in origin in which curd not far removed
from cottage cheese is the basis of the product. Harz cheese is one of
the best-known of these forms as studied by Eckles and Rahn.[42] One of
these forms, hand cheese,[43] is manufactured on a commercial basis in
farm dairies among families of German descent principally in
Pennsylvania, and on a factory basis in a few places in New York,
northern Illinois and Wisconsin. On the small scale, curd is made by
natural souring or by use of starter, heated to expel water, cooled and
molded by hand into cakes two to three inches in diameter and one-half
to three-quarters inch in thickness. The freshly formed cakes are placed
upon a shelf to dry. There they are turned daily until fairly firm, then
packed in rolls into wooden boxes and ripened in a cool damp room. In
this ripening there is a prompt development of a heavy viscous slime,
which consists of Oidium and bacteria. Other molds forming loose cottony
mycelium are brushed off if they appear. The proper consistency of this
slimy covering depends on a close adjustment of water-content in the
cheese with temperature and relative humidity in the ripening room. If
conditions are too dry, the cheeses harden quickly or if less dry they
are attacked by green or blue-green molds. If too wet, the slimy
covering becomes too soft and watery, or secondarily covered with loose
shimmering masses of mold (Mucor sp.). Ripening should proceed slowly
and occupy a period of six to eight weeks.
+140. Pennsylvania pot cheese.+--A form of "pot" cheese is made in
certain counties of Pennsylvania, principally for local use. Production
of this cheese on a factory basis is now being attempted. The steps in
manufacture are about as follows:[44] (1) The home-made type of cottage
cheese curd is prepared, put into a crock or pot and covered carefully;
(2) kept in a warm place (in kitchen usually); (3) stirred from time to
time, until it has ripened to a semi-liquid condition. This occurs very
rapidly under the attack of _Oidium lactis_ accompanied by bacteria.
Within a period of three to seven days, according to the temperature and
to the water-content of the mass, the granules of curd become covered
with a wrinkled gelatinous almost viscid mass of mold mycelium beneath
which is a layer of semi-liquid curd with a strong characteristic odor
and taste. This ripened or semi-liquid part reaches about half the total
mass in four or five days at favorable temperatures. (4) The vessel is
then placed in a larger vessel of water and heated over the fire with
constant stirring until the whole mass is melted and smooth. (5) Butter
or cream, and salt or other flavor is finally added, stirred in and the
liquid cheese poured into molds or jelly glasses to cool. If properly
made and cooked, the resultant cheese has a soft buttery consistency
with an agreeable flavor, which frequently resembles that of Camembert
cheese.
+141. Appetitost (Appetite cheese).+--A Danish buttermilk cheese is made
under this name. Sour buttermilk is heated, by some to boiling
temperature but others (Monrad[45]) prefer 120° F., stirred thoroughly
and allowed to settle. The whey is removed as far as possible. The
semi-liquid mass is covered and set in a warm place. Fermentation
becomes active. This tends to make the curd more viscous or sticky. It
is then kneaded and allowed to ferment again. This process is repeated
until the mass is yellowish and soft but tough or viscous. When
thoroughly fermented, the mass is again heated to 120° F., and 6 per
cent salt is added together with spice; both are worked in and the
cheese is formed into fancy shapes for sale.
+142. Ripened Neufchâtel, French process.+--Neufchâtel as a ripened
cheese is made rather widely in France but it is produced on an
especially large scale in Seine-Inferieure.[46] Some factories use whole
milk, or milk with added cream, others skimmed-milk.[47] The whole-milk
brands of Neufchâtel are those which have the widest reputation. For
making this cheese, the working room is held as closely as possible at
15-16° C. (58-60° F.). The milk is strained into earthen vessels holding
twenty liters. Rennet is added to the freshly drawn milk at about 30° C.
(86° F.) in amount sufficient to produce coagulation in about
twenty-four hours. Draining racks of various forms are covered with
cloth. The vessels of curd are dumped upon the racks. The whey separates
slowly and drains off through the cloth. About twelve hours are allowed
for this process. The corners of the cloth are then brought together
and folded in or tied and the mass pressed to complete the drainage. The
finished curd is worked or kneaded to produce a smooth and uniform
texture. This process of curd-making is essentially the same as the
American factory process of making Neufchâtel. The ripening process has
been entirely dropped in America. The curd is finally molded in metal
forms 5 cm. (2 inches) in diameter and about 6.7 cm. (about 3 inches)
high, open at both ends. These molds are filled, the freshly formed
cheeses are pressed out with a plunger or piston and their surfaces
smoothed with a wooden knife.
After molding is completed, the cheeses are salted by sprinkling the
entire surface with fine dry salt as the cheese is held in the hand. In
this way each cheese receives and absorbs 3 to 4 per cent salt. After
salting, the cheeses are arranged upon boards and allowed to drain
twenty-four hours. They are then removed to the first or drying room.
The frames of the drying room (secherie) are covered with straw and the
cheeses are placed carefully upon the straw to avoid contact with each
other. They are turned each day to present a fresh surface to the straw
during a period of two to three weeks in the drying room (secherie).
Mold begins to show as white cottony mycelium after five to six days,
and slowly turns to "blue" (bluish green). When the cheeses are well
covered with this moldy rind, they are removed to the ripening cellar.
In the ripening cellar also the cheeses stand upon straw. They are
turned over every three or four days at first, then allowed to stand for
a longer period.
When ripe, a Neufchâtel cheese so made weighs about 125 grams. One
liter of milk makes 225 grams of such cheese. The ripening of Neufchâtel
has never been fully studied, but a series of these cheeses were
obtained by one of the authors; cultures were made and examined.[48] The
salt-content in the first place was found to be so high that _Oidium
lactis_ was eliminated as an active factor in the ripening. The mold
proved to be on some cheeses _Penicillium Camemberti_, the typical mold
of Camembert as it is made in Normandy, on others _P. Camemberti_ var.
_Rogeri_, the pure white form as used under the patents of M. Georges
Roger in the region of Seine-et-Marne to the eastward of Paris and
called by him and by Mazé _P. candidum_. The physical condition of the
ripened curd and the flavors encountered were those associated with
these two species by many hundreds of experiments during the Camembert
investigation in Connecticut.[49] These facts justify the conclusion
that ripened Neufchâtel is first soured by lactic organisms, then so
salted as to eliminate or reduce to a minimum the characteristic
activities of _Oidium lactis_, while the proteolytic action and the
physical changes are closely similar to those of Camembert which is
ripened primarily by the same molds.
+143. The Camembert group.+--The soft cheeses ripened by molds are
French in origin. Their manufacture has spread into Germany, Italy and
America. Of the series, the most widely known is Camembert, which will
be described as typical for the group. Brie, Coulommiers, Robbiola and
Ripened Neufchâtel belong to this series.
+144. Camembert cheese.+--The origin of Camembert is given by French
authorities as 1791 in the Commune of Camembert near Vimoutiers in Orne,
France. From a very restricted production at first, Camembert-making has
spread through the region from Caen in the west to Havre, Rouen and a
considerable area east of Paris. In America Camembert began to be made
in one factory about 1900. Several other factories followed by 1906. The
difficulties and losses encountered led to the abandonment of these
undertakings, until at the outbreak of the European war in 1914 but one
factory was making Camembert and that only on an experimental scale.
Meanwhile the United States Department of Agriculture and the Storrs
Experiment Station had taken up and solved, on an experimental basis,
most of the problems arising in these commercial failures. A shortage of
product at the outbreak of the war brought about the re-establishment of
a series of factories. The product as put on the market indicates that a
permanent establishment of Camembert-making is entirely practicable.
Camembert cheese is made from cow's milk either whole or very slightly
skimmed; the removal of about 0.5 per cent of fat has been found to be
desirable if not actually necessary.
+145. Description of Camembert.+[50]--These cheeses are made in sizes
2½ to 4½ inches in diameter and 1¼ to 1½ inches in thickness. They are
ripened by the agency of molds and bacteria which form a felt-like rind
over their whole surface, 1/16 to 1/8 of an inch in thickness. This rind
may be dry and gray or grayish-green, consisting of a felt-like surface
of mold on the outside, below which a harder portion consists of mold
embedded in partially dried cheese, or the moldy part may be more or
less completely overgrown or displaced by yellowish or reddish slime
composed mainly of bacteria. Good cheeses may have either appearance.
Inside the rind, the cheese is softened progressively from the rind
toward the center from all sides, so that a fully ripe cheese has no
hard sour curd in the center, but is completely softened. No mold should
be visible inside the rind, but the moldy rind itself is necessary
because the ripening is caused by the enzymes secreted by the organisms
of the rind into the cheese. As the curd ripens, the changed portion
assumes a slightly deeper color than the unripe curd as a result of
chemical changes. Well-ripened cheeses vary from nearly a fluid texture
to the consistency of moderately soft butter. The ripening of Camembert
is finished in wooden boxes which protect the cheeses from breaking
after they become soft and during the market period.
+146. Conditions of making and ripening.+--These processes depend on a
very close adjustment between the composition of the freshly made cheese
and the temperature and humidity of the rooms in which the cheeses are
made and ripened. Very slight failures in control bring loss in ultimate
results. The room for making Camembert should be maintained between 60°
and 70° F. and should be wet enough to reduce drying to a minimum. The
essentials of apparatus are comparatively inexpensive. Work on a factory
basis calls, however, for the installation of special tables and other
apparatus to utilize space and labor to advantage. Rooms are protected
from change of weather by double sash in the windows. Flies must be
excluded by close-meshed screens for all doors and windows with movable
sash. The equipment installed in such a room is shown in Fig. 18.
Curdling cans are ranged on a shelf a few inches above the floor along
one side of the room below an open tin trough with side branches. This
open trough brings the milk from the mixing vat to the curdling cans.
(The open tin trough offers no lodgment for dirt.) The cans hold about
200 pounds of milk, are about 12 inches in diameter at bottom, and 20 to
24 inches at top. They are heavily tinned. Iron trucks as high as the
shelf and with tops the same diameter as the bottoms of the cans form a
convenient method of bringing cans of curd to the very edge of the
draining tables.
[Illustration: FIG. 18.--Camembert cheese-making room in an American
factory.]
[Illustration: FIG. 19.--Draining mat for Camembert cheese.]
The wooden draining tables are placed about 32 inches above the floor;
they are usually made of 2-inch lumber, have raised edges and slope
slightly toward the wall. Whey and wash water are thus carried to a
draining trough along the wall. For cheese-making, each is covered with
a strip of matting consisting of wooden strips held together by thread
(Fig. 19). The strip of matting should be exactly the width and length
of the table. The hoops used are heavy tin, with edges turned and
soldered, about 5 inches high, 4-5/8 inches in diameter with three rows
of holes about 1/12 inch in diameter and 2 inches apart in the row.
These hoops are placed as thickly as possible upon the mats.
+147. Outline of making process.+--The making process[51] is summarized
as follows (Thom, 1909):
_Starter._--From 0.5 to 1.0 per cent of active starter is added to milk
kept overnight below 60°F.
_Acidity at renneting._--Milk titrated to phenolphthalein should test
0.20 to 0.23 per cent calculated as lactic acid.
_Temperance of renneting._--84°-86° F. is used for Camembert.
_Rennet._--From 3 to 5 oz. of standard rennet extract to 1000 lb. milk
(10-15 c.c. per 100 lb. milk) produces a curd of proper texture.
_Curdling time._--To reach the proper condition for handling, 1¼ to
1½ hours or longer is required. This is indicated by the onset of
"sweating" or the separation of large drops of whey on the surface of
the solid curd.
_Dipping._--A long-handled dipper is used to transfer curd from cans to
hoops. This can be lowered into the hoop. This transfer is to be done
with the least possible breaking. One dipperful is transferred at a time
to each of a series of hoops. By the time the series is covered, some
drainage has occurred and a second dipperful is added to the contents of
the hoop. In this way the hoop is filled within a period of two to four
hours.
_Draining._--Hoops when properly filled have taken in approximately 2
quarts of milk each. No pressure is used. Cheeses drain by gravity. They
stand unturned until the following morning when they should be firm
enough to permit turning without removing the hoops. The cheeses when
firm enough to handle (usually on the third morning) are salted by
dusting the entire surface with coarse salt and permitting all that
adheres to remain. The cheeses should then be removed to a room at about
58°F. to prevent too rapid leakage of water and salt from their
surfaces. Ripe cheeses of good quality show a total salt-content varying
from 2.25 to 3 per cent with an average of about 2.5 per cent. When so
handled there is slight, if any, loss of water and salt in the salting
period of twenty-four to forty-eight hours. At the end of the salting
period such cheeses should carry 55 to 57 per cent water or slightly
more.
+148. Acidity.+--The essential biological factor in the making period of
Camembert is proper souring. The milk should be free from gassy
organisms. The lactic starter required should introduce the typical
lactic organism (_Streptococcus lacticus_) in numbers sufficient to
suppress all other forms during the next twenty-four hours. The amount
of acid starter introduced, however, plus the acid resulting from growth
during the curdling period, should not produce a grainy acid curd. The
temperatures of handling are such as to favor this group of organisms if
properly introduced and permit the development of nearly 1 per cent of
acid (estimated as lactic) by the second morning. Cheeses with such acid
are fairly free from further danger from bacterial activity. Members of
the high-acid group (_B. Bulgaricus_ and allies) may be found in these
cheeses but do not appear to develop in numbers sufficient to affect the
cheese to any marked degree.
[Illustration: FIG. 20.--Halloir, the first ripening room for Camembert
in an American factory.]
CAMEMBERT CHEESE RECORD
Date_______________ Set__________ No._____
Amt. milk___________ No. cheese_____ Milk per cheese________
Producer of milk_______________
Apparent cleanliness of milk_______________
+Acidity:+
Before adding starter____________________
After adding starter____________________
After acidity period____________________
Whey at dipping_______________
+Starter:+
Kind_______________ Age_____ Amt_____
+Color:+
Amount_______________
+Curdling:+
Temperature used__________
Amount of rennet__________
Time at which rennet is added__________
Time at which milk is curdled__________
Time of curdling__________
Quality of curd____________________
+Dipping:+
Cut or uncut_______________
Amt. of cutting_______________
+Draining:+
Temperature of room during__________
Condition of cheese after____________________
+Salting:+
Time of_____ Total amt. of salt used_____ Kind of salt_____
Amt. of salt per cheese_____
+Mold inoculation:+
Form of culture used_______________
Method of inoculation______________
Time of inoculation__________
+Remarks on making:+
+Curing:+
Transfer of curing rooms_________________________
Condition of cheese______________________________
Rooms____________________________________________
Dates____________________________________________
+Mold growth:+
Date of first appearance____________________
Purity and vigor____________________________
Date of changing color______________________
+Surface of slimy growth:+
Extent of___________________________________
General character of________________________
+Surface contamination:+
Mold________________________________________
Oidium______________________________________
Yeast_______________________________________
Bacterial___________________________________
+Wrapping:+
Date_______________ Material____________________
Condition of cheese_________________________
+Ripening:+
Rapidity of_________________________________
Texture_____________________________________
+Flavor:+
Ripened curd________________________________
Unripened curd______________________________
+Special treatment and reasons for same:+
Record of treatment by days____________________
Room__________ Date__________ Observations.____________________
1 D_____ 16 D_____
2 D_____ 17 D_____
3 D_____ 18 D_____
4 D_____ 19 D_____
5 D_____ 20 D_____
6 D_____ 21 D_____
7 D_____ 22 D_____
8 D_____ 23 D_____
9 D_____ 24 D_____
10 D_____ 25 D_____
11 D_____ 26 D_____
12 D_____ 27 D_____
13 D_____ 28 D_____
14 D_____ 29 D_____
15 D_____ 30 D_____
31 D_____
+149. Ripening the cheese.+--The cheese is now ready for the ripening
rooms (Fig. 20). For this process temperatures between 52° and 58°F. are
desirable; lower temperatures only delay the process; higher
temperatures favor undesirable fermentations. The cheeses rest upon
coarse matting (Fr. clayons) consisting of round wooden rods about the
size of a pencil separated 1-1¼ inches and held in position by wire
strands. Assuming cheeses of optimum composition as indicated above, the
relative humidity of the ripening rooms should be 86 to 88 per cent.
Higher humidities produce too rapid development of slimy coatings; too
low humidity is indicated by drying, shrinkage and the growth of green
molds on the surface. A slight and very slow evaporation is demanded; by
this the water-content of the cheeses is reduced 3 to 6 per cent in two
weeks. During the first two weeks of ripening, the cheeses commonly show
some growth of yeast and _Oidium lactis_ first, followed by cottony
white areas of Camembert mold (_Penicillium Camemberti_). This mold must
be introduced by inoculation in new factories but once firmly
established in the factory will propagate itself if conditions are kept
favorable. Climatic conditions in most dairy sections of America have
been sufficiently unfavorable to make more or less continuous use of
pure cultures desirable. At the end of two weeks, Camembert cheeses
should show a well-established rind, consisting of a well-matted felt
work of mold hyphæ through the outer 2 mm. (1/12 inch) of the whole
surface of the cheese. More or less of the pale gray-green fruit of the
characteristic _Penicillium Camemberti_ can usually be seen. Beginning
at about twelve to fourteen days,[52] a softening of the curd is first
directly detectable under the rind. This is preceded by the
disappearance of the acidity of the curd, which progresses inward. The
softening of the curd follows closely the lowering of the acidity. Thus
a litmus test taken along the cut face of a Camembert cheese at any
stage of softening will always show a sharp acid reaction in the solid
sour portion which changes to alkaline just before the softening due to
proteolytic action becomes noticeable. These two changes appear to be
due to enzymes secreted by the mycelium of the _Penicillium Camemberti_
and _Oidium lactis_ which constitute the most active factors in the
ripening. Some accessory bacterial action is indicated but of minor
importance in the changes found.
To avoid loss from breaking, after the softening of the curd has fairly
begun, the cheeses must be removed from the coarse matting to smooth
boards where they are watched and turned repeatedly, or as in the more
common practice, wrapped at once in parchment paper and boxed. The
ripening may be completed in either way. The conditions necessary are
such as to favor the extension of slimy areas of bacteria over part or
all of the rind to the exclusion of further development of gray-green
fruiting areas of mold.
Complete softening may occur in three weeks in cheeses in which
evaporation has gone on too slowly. Such cheeses are found to contain 51
to 55 per cent of water when ripe and decay very quickly. If handled
properly, the water-content should fall from about 57 per cent at the
beginning of ripening to 48 per cent at its completion which should
require a minimum period of about four weeks. It is more desirable that
a cheese four weeks old show a thin core of sour curd in the center than
that it be entirely liquid at that age.
[Illustration: FIG. 21.--Very soft Camembert cheese.]
+150. Composition.+--Properly ripe Camembert shows about the following
range of composition: Water 47 to 49 per cent; fat 25 to 28 per cent;
protein 18 to 21 per cent; salt 2.2 per cent to 2.8 per cent. Variations
outside these limits are usually associated with less desirable
qualities. The approximate limits and characters outlined for Camembert
still leave a considerable latitude for variations in practice which
characterize the output of particular factories in a producing group. At
one extreme are brands of Camembert cheese which are very soft (Fig.
21), some of them actually liquid when ripe, and which have very strong
odor and taste; one such brand has held first place in the trade of
certain American cities for years. Another popular brand when fully ripe
is well covered with yellow-orange viscid slime[53] but is fairly firm
in texture with high flavor; still others show dry moldy surfaces and
mild flavors. The product of certain factories is always characterized
by the presence and characteristic ammoniacal odor of _Penicillium
brevicaule_.
Each of these forms seems to appeal to some classes of consumers, so
that in handling imported Camembert the trade comes to assign the
product to specific groups of purchasers according to the conditions
observed at its arrival from Europe.
[Illustration: FIG. 22.--Camembert cheese factory at Lisieux, France.
The square windows are seen in the second-floor rooms.]
+151. Factory.+--The type of factory to be used in making and ripening
Camembert must be adjusted to the climate. This product originated in
the Normandy section of France which is but a few feet above sea level,
is swept by winds from the Gulf Stream, and has a narrow range of
temperature, with highly humid conditions. In that region, every effort
must be made to secure ventilation to carry off the necessary amount of
evaporation water. In contrast, most of the dairy sections of America
have land instead of sea breezes, much higher altitudes, much greater
extremes of temperature and a lower range of relative humidities. The
conditions of an upstairs room full of windows in Normandy (Fig. 22) are
most readily reproduced in rooms partly or completely below ground in
this country. The industry calls for the production and maintenance of a
specific set of working conditions. These are furnished by nature in
northern France, probably also in certain Pacific coast areas, but must
be artificially obtained where the climate is unfavorable.
+152. Economic factors.+--Camembert cheeses show a yield of about 13
pounds to 100 pounds of milk testing 4 per cent fat. At roughly one-half
pound each, the number of cheeses will be approximately twenty-six.
Assuming no losses and a wholesale price of 15 cents each, the wholesale
value of 100 pounds of milk would be $3.90. The labor cost of production
is high, the package represents (box, wrapping and label) at least 1½
cents a cheese. The time between the purchase and the consumption of the
cheese will average about one month. Few cheeses actually remain this
length of time in the possession of the maker. This short investment
period, therefore, is a distinct advantage of Camembert. Among
disadvantages, however, the extremely perishable character of the fully
ripe cheese makes provision of an adequate and constant market
essential. Losses due to failures in manufacturing or ripening
conditions are also frequent. Excessive heat in summer and very cold
periods in winter are both unfavorable. The Camembert-maker cannot,
therefore, use the cheapest milk of the summer months at all and the
losses entailed by failure of control in winter fall on the most costly
milk of the year. Camembert requires, therefore, careful selection of
the location for manufacture and ripening, effective control of
conditions throughout the period and adequate marketing facilities.
Camembert at its best is one of the finest of all cheeses; when bad, it
becomes quickly inedible and is a total loss.
+153. French Brie.+[54]--Brie cheese has its center of production in
Seine-et-Marne, east of Paris in northern France. The apparatus,
arrangement of the factories and details of manipulation differ from
those described for Camembert, but the final product is in flavor and
texture closely related to Camembert. Brie cheeses are the same
thickness as Camembert, 1 to 1¼ inches; in diameter, however, there
are three or more sizes varying from 8 to 16 inches, or even greater.
The largest cheeses weigh 5 to 6 pounds. As in Camembert, practices of
making and ripening vary to such a degree as to produce various
qualities of product. These run from whole milk through all shades of
skimming. Perhaps the best established practice puts the cheese-making
room next to the stalls of the cows. The milk is drawn, strained
directly into the curdling cans and renneted while still warm,--86-92°
F. (30-33° C.). No lactic starter is added and no ripening period is
given to the milk. The other manipulations differ only in detail from
Camembert. Ripening of Brie follows the same course with the same
organic agents, namely, Camembert mold (_Penicillium Camemberti_) and
_Oidium lactis_ with the accompaniment of a mixture of slimy organisms
upon the surface of the cheese. The process admits of many minor
modifications each capable of affecting the product in a characteristic
way. The judgment and skill of the maker is given a wide opportunity to
establish and work toward a particular ideal of appearance and texture
and flavor. Brands with characteristic qualities, therefore, command
their own market.
Brie as known in France must not be confused with the American
"d'Isigny," or with the particular sizes of that type which have been
called Brie on account of diameter only. Very little Brie as known in
France has been made in America and only a limited amount has been
imported for very restricted trade.
+154. Coulommiers.+--Another member of the Camembert group is called,
from its place of origin, Coulommiers. This form is made at the same
thickness as Camembert and about 5¼ inches in diameter. It appears as
either a ripened or unripe cheese. As a ripened cheese, Coulommiers is
not essentially different from Camembert except that some brands are
made without salting. As a cheese eaten unripe, it has certain
advantages over the other cheeses with the flavor of sour milk only. The
cottage and (American) Neufchâtel group of cheeses comprises the best
known forms with the acid flavor. These cheeses are very perishable in
nature. On the other hand, Coulommiers as eaten fresh can be held and
used over a much longer time without loss. Coulommiers[55] in this sense
is simply a fresh Camembert. Such a cheese, when ready for the salting
process, is a firm sour mass, close textured, almost impervious to air
and but slowly permeable to liquids. Spoilage in such a cheese begins
only on the outside, and not throughout the mass as in cottage cheese or
Neufchâtel. Successive portions of such a cheese can be removed daily
over a considerable period with no loss of substance aside from slight
scraping at times and little or no change in flavor. This product has
very tangible merit for manufacture and use on the farm in many sections
of America.
CHAPTER IX
_SOFT CHEESES RIPENED BY BACTERIA_
A bacterially-ripened series of cheeses parallels the mold-ripened group
as typified by Camembert. Although the varieties overlap, these may be
roughly grouped as: (1) those made from friable or soft curd; (2) those
made from firm or rubbery curd. In the first group, the curd is set at
86° F., or below; in the second, the rennet is added at 90° F. or above.
In the first, the lower temperature and long curdling time with ripened
milk gives a soft friable curd which may be toughened somewhat by
cutting and stirring in the whey. This section is typified by d'Isigny,
American Brie, Liederkranz. In the second, curdling of unripened milk at
temperatures of 90° F. or above insures a smooth elastic curd which
fuses more or less completely into the firm rubbery mass typified by
freshly made Limburger.
+155. The Isigny group.+--A series of names, d'Isigny, Brie, Brie
d'Isigny, combined with trade names, are used for a domestic cheese,
made in a small number of factories distributed over New York,
Pennsylvania, Michigan, Illinois, Wisconsin, Iowa and California. The
cheeses sold under the separate varietal names differ only in diameter;
their thickness is fairly uniform; the process of manufacture and
ripening with resultant textures and flavors furnishes no fundamental
varietal characters, although the products of the several factories show
noticeable differences in market quality. D'Isigny, while the name of a
French town famous for butter production, is not used to designate a
cheese in France. It may, therefore, be accepted as a French name
arbitrarily applied to a domestic product. Brie as used in France is a
markedly different cheese (p. 131), and the name should be dropped from
this form as made in America. As used for a member of this series made
in America, it merely means cheese 7 to 15 inches in diameter. The
cheese partakes of the characters of French Livarot, and of Pont
l'Eveque without exactly reproducing either form.
The milk varies from separator skim to whole milk, with resultant
differences in quality. Freedom from gas is essential to the best
results. The milk is curdled at 85° to 86° F. with sufficient rennet to
produce a very firm curd within a period of one and one-half hours. Curd
is then cut in two directions, allowed to stand a few minutes or gently
agitated to produce a very slight toughness or "worked" condition, then
scooped into hoops 4½ to 5 inches in height and varying in diameter
from 2½ to 15 inches according to the size selected for manufacture.
To aid in the escape of whey, three rows of holes 1/12 inch in diameter
and 2 inches apart in the row are made in each hoop. The hoops are
arranged upon draining tables with more or less corrugated surface,
which for best drainage should be covered with matting. The cheeses are
allowed to drain without pressure. They are commonly turned the second
morning, although they are sometimes solid enough to turn within the
first day. When fully drained, the cheeses are salted by rubbing coarse
salt on the surface, after which they stand an extra day. They are then
arranged upon shelves in a ripening room held between 50° and 60° F.
with humidity so high that evaporation is kept at a minimum. In this
room, a surface slime develops quickly. This consists of bacteria of
several forms, yeasts, _Oidium lactis_ and accidental species of other
molds. During this ripening, the cheeses are turned, rubbed with the
hands, washed with salt water and scraped if infected with molds which
produce colored colonies. In the course of ripening, the slimy surface
layer acquires a yellowish orange color with the strong odor and taste
characteristic of the series.
Brands of d'Isigny are made from every grade between separator skim and
whole milk. They reach the market in condition all the way from "Kosher"
forms[56] which are eaten entirely unripe, to brands which approximate
the qualities of Limburger and others which approach Port du Salut.
The biology and chemistry of the ripening of this type of cheese have
not been completely followed. An initial souring process always takes
place quickly. _Oidium lactis_ is always present in some degree on the
surface, but the organisms in the yellowish to orange slime on the
surface of the cheese appear to produce the characteristic odor and
taste. These appear to be due to the development of volatile fatty
acids, such as valerianic and caproic, which diffuse throughout the
cheese, even penetrating the unripened sour portions. The same odor and
taste in varying intensity are present in Limburger, Brick, and a long
series of German varieties not handled in America.
High-flavored cheeses such as these, form an acceptable part of the meal
in cases in which the intensity of other flavors is such as to mask
entirely the milder flavors of Camembert or cream cheese.
In composition, a characteristic whole-milk brand of this group showed
the following analysis:[57] water, 45.5 per cent; fat, 25.28 per cent;
protein, 18.22 per cent.
+156. Raffiné.+[58]--This cheese is made in the French settlement of the
Isle of Orleans in the St. Lawrence River. The practice seems to have
been brought from France and represents an intermediate product between
Camembert and perhaps Livarot, a cheese on the borderline between
Camembert and Isigny as made in America. The outline of the making
process as given follows: Milk freshly drawn is curdled without cooling,
at approximately 90° F. The rennet is prepared on the farm. About
one-half hour is required for curdling. The curd is cut into 2-inch
cubes. Whey is removed as fast as it separates. About two hours are
required for draining. The curd then goes into the hoops. The metal
hoops, which are closed at one end, are 6 inches high, 4½ inches in
diameter, with holes about 1/16 inch at intervals of about ½ inch, and
stand upon three legs about 1 inch in height. When filled, the cheeses
are left on a draining table. Some salt is put on top while draining.
When the volume is reduced to one-half, the cheese is turned. The
draining room is kept at about 70° F. After they are firm enough to
handle, drainage is completed on racks covered with rush matting. These
are arranged on special racks. The cheeses are turned twice a day, and
washed in slightly salted water every two days. After each washing, they
are drained for two hours on cloth, and placed on clean matting. This
treatment continues about fifteen days.
After fifteen days on the matting, the cheeses are ready for ripening.
They are first covered with cold brine and let stand twenty-four hours.
The cheeses are packed in rolls or tiers in boxes, covered with cloth
and ripened at 45° F. They must be kept moist; if signs of drying
appear, moisture must be added. If the cheeses develop yellow slime,
they are washed with clear water and rinsed in water with salt added.
After a ripening period of three weeks, the cheeses should begin to be
soft when pressed with the finger. The growth of molds must be prevented
by washing the boxes, cloths, and washing and scraping the cheeses if
necessary. When the cheeses are ready for the market, they are scraped
clean and white, wrapped separately in cheese-cloth or parchment paper
and packed into the boxes. Ripe cheeses are about 5 inches in diameter,
1 inch thick and weigh a little over 5 ounces.
The outline of the Raffiné process follows:
coagulation by rennet 30 minutes
cutting and draining curd 2 hours
draining in hoops 10 hours
stand on mats 15 days
ripening in boxes 21 days
Total period 36 days
The treatment described closely resembles the handling of Livarot cheese
in the department of Calvados, France.
+157. Liederkranz cheese.+--Among the specialties in the bacterial group
is Liederkranz, made from curd with the soft friable texture of a
Camembert, molded in rectangular blocks of about 4 ounces in weight and
ripened very completely. Although this name is the private brand of a
single factory, it has become widely known with the effect of creating a
type name in the American market. Analysis of this brand of cheese
gives about 55 per cent water, 25 per cent fat, 17 per cent protein,
which indicates a whole milk cheese.
+158. Limburger cheese+[59] derives its name from the town of Limburg in
Belgium. The manufacture of this cheese is now widely practiced in
Europe and in certain parts of the United States, especially in New York
and Wisconsin. Practically no cheese of this name is at present
imported, and the practices described are limited to those in American
factories.
+159. The milk.+--Limburger cheese is probably best known on account of
its pronounced odor. Because of this characteristic pungent smell, it is
often thought that the cheese is made in dirty or unsanitary places. On
the contrary, Limburger cheese is usually made in small factories which
are clean and sanitary. Because of the constant attention required, a
cheese-maker can handle only about 2000-2500 pounds of milk a day, and
then some help is necessary to care for the cheeses in the curing
room.[60] The discussion of the milk given in Chapter II applies to that
to be made into Limburger cheese; however, Limburger requires sweeter
milk than do some of the other types. To be sure of obtaining very sweet
milk, it is the usual practice for the milk to be delivered without
cooling morning and evening at the cheese factory. The cheese is made
twice a day. Because the milk must be delivered twice daily, it is
obtained from only a few producers near the factory. A factory usually
does not have more than eight to twelve patrons. Because of the small
number of patrons, it is comparatively easy to obtain a supply of fresh
clean milk.
[Illustration: FIG. 23.--A common type of Limburger cheese factory.]
The factories are variously built. A common type takes advantage of
sloping ground so that the floor at one end may be on the ground level
and run backward into a hillside until the other end is a cellar with
small windows at the ceiling opening at the ground level (Fig. 23). The
family of the cheese-maker often lives in the same building above the
factory.
+160. Making the cheese.+--Limburger cheese is made from the whole milk.
When the milk is received at the factory, it is placed in the cheese
vat. As the milk is delivered both morning and evening without cooling,
it reaches the factory at a temperature of 90 to 96° F. In some cases
the night's and morning's milk is mixed and then warmed to about 94° F.
This practice is not recommended but is frequently adopted, when the
supply of milk becomes too small to work in two lots. As soon as all of
the milk has been delivered, the cheese-making process begins. No
starter is used. The milk is not ripened because no acid development
during the making process is desired. The milk is set or curdled at the
temperature at which it is received at the factory, usually from 90 to
96° F. Sufficient rennet extract is used to give a firm coagulation in
twenty to thirty minutes. This usually requires 2½ to 3 ounces of
rennet extract for each 1000 pounds of milk: This is diluted in about
forty times its own volume of cold water and added to the milk. (For
method of adding rennet extract to milk, see Chapter V.) When the
coagulum has become firm so that it will split clean over the finger,
the curd is ready to cut. Coarse Cheddar cheese knives are used.
Sometimes only the perpendicular knife is employed, and the curd is
broken up while being stirred with the hands and rake. This usually
causes a large fat loss. After cutting, the curd is stirred first by
hand and later with an ordinary wooden hay rake. Usually the curd is not
"cooked" or heated after setting, though occasionally it is brought up
as high as 96° F. to 98° F. If the curd does not firm up, the
temperature may be raised to 98° to 100° F. to aid in expelling the
moisture.
When ready to dip, the curd should still be in large soft shiny pieces.
It requires from one hour to an hour and thirty minutes from the time
the rennet extract is added until the curd is ready to dip. When, in the
judgment of the cheese-maker, the curd has become sufficiently firmed in
the whey, the whey is drawn down to the surface of the curd. The curd is
then dipped into the Limburger molds. These molds are 5 inches square by
8 inches deep without top or bottom. Usually there are five or six of
these molds built together into a section. These molds are placed on a
draining table beside the vat and the curd is ladled into them with a
large tin ladle. The draining table has strips on both sides and one end
and slants toward the other end so that the whey will drain from the
curd and yet not go on the floor except at the one end. This makes it
easy to save and catch the whey for stock feed.
+161. Draining and salting Limburger.+--In some factories, a clean piece
of burlap is put on the draining table and the molds and curd placed on
the burlap. This aids in the rapid draining of the whey from the curd
and prevents the loss of curd particles. The curd should be turned
frequently in the mold to obtain uniform draining. The molds are
transferred to the salting room as soon as well drained, usually in
about twelve hours, but sometimes they are left until the following
morning. Here they are placed on another draining table, which has
strips about 5 inches high on the sides and one end. The cheeses are
placed along this board, each cheese being separated by a piece of board
4 inches high and 5 inches wide. When the row is filled, a long strip
the length of the table is placed against the row. Another row is laid
down against this strip in the same manner as the first, and so on until
several rows are on the table. The last long strip is held firmly in
place by sticks wedged between it and the opposite side of the table.
These strips and pieces form a mold for each cheese while draining.
Usually the cheeses are turned several times in this period to obtain a
uniform expulsion of whey. In about twenty-four hours the cheeses are
ready to be salted. This is done by applying the salt to the outside of
the cheese. The edges are rolled in a box of salt and the salt then
rubbed on the two broad surfaces. Any excess salt is brushed from the
cheese with the hand. The cheeses are then laid on a draining table in
single layers. The second day, they are salted again in the same way and
piled two deep; they are salted again the third day and piled three or
four layers deep. The salting room or cellar should have a temperature
of 60° F. and be fairly damp. The amount of salt used is very important.
The tendency is to use too much salt. This retards the ripening process
and in extreme cases gives the cheese a salty taste. If not enough salt
is used, the cheese will deteriorate very rapidly on account of the
development of undesirable types of fermentation. The cheeses when
salted are then placed in the curing room, which is a cellar, usually
beyond the salting room. This cellar should have a temperature of 58° to
64° F. and a relative humidity of 95 per cent of saturation. In winter
it is necessary to have a fire to keep the rooms warm, otherwise the
cheese would cure very slowly or not at all. In some factories the
curing and salting cellars are a single room.
+162. Ripening Limburger.+--When first placed in the curing cellar, the
cheeses are put on edge close together, and as they cure are gradually
separated. While in the curing cellar, the cheese must be rubbed
frequently by hand and washed, usually with salt water. The object of
the rubbing is to keep the surface of the cheese moist and prevent the
growth of molds. The drier the cheese and the more mold, the oftener the
cheeses must be rubbed. The drying or the evaporation from the cheese
can be retarded by sprinkling the floor of the cellar with water. When
first placed in the curing cellar, they are usually rubbed daily; after
a few days they are rubbed every other day and finally as often as the
cheese-maker can find time to work at them. The more the cheeses are
rubbed, the better the rind.
In the curing of Limburger cheese, protein compounds are attacked by the
micro-organisms. Certain highly-flavored fatty acids are commonly
produced.[61] This change works most rapidly near the outside and more
slowly toward the center of the cheese. The stage of ripening can be
determined by examining the cheese. When first made, a cheese is harsh
and hard and the outside is more or less white: as the curing changes
take place, the cheese becomes soft and pasty or buttery. The outside
color changes from a whitish to a yellowish and finally even a reddish
brown. It requires considerable time for the ripening agents to work
from the outside to the center of the cheese. As ripening progresses,
Limburger cheeses tend to become soft enough to break in handling. If
such cheeses are wrapped in manila paper after three to four weeks of
ripening and packed in boxes, losses from handling are eliminated. One
loose board is left on each box and the boxes remain in the ripening
cellar until the cheese-maker decides by removal and examination of
cheeses from time to time that they are ready for shipment. When fully
ripe, the cheese spoils very quickly. Unless handled very carefully, the
outer part may actually rot before the interior is fully ripe. The
cheeses are shipped from the factory when they are eight to ten weeks
old. They are then placed in cold storage, which checks the action of
the ripening agents and so lengthens the commercial life of the cheese.
+163. Marketing and qualities of Limburger.+--As shipped from the
factory, each cheese is wrapped in heavy manila paper and frequently
also in tin-foil. The cheeses are packed in boxes which hold
forty-eight. Each cheese weighs about two pounds.
Limburger cheese should be regular in shape. The rind should not be
cracked or broken nor the sides bulged, nor should it be lopsided. It
should have the pronounced characteristic flavor, without other
objectionable flavors due to undesirable fermentations. The body should
be uniform throughout. It is common to find cheeses that have not a
uniform body, due to lack of curing; a small part of the interior at the
center will be hard and not cured, while the remainder of the cheese
will be soft and buttery. The color should be uniform. When not entirely
cured, the uncured part at the center is usually of a lighter color.
The cheese should contain the proper amount of salt. The most common
defect is in the flavor. If the milk is not free from bad odors and
flavors, these are apt to be more pronounced in the cheese than in the
milk. (For care of milk see Chapter II.) Gas-forming fermentations are
very bad in this variety of cheese as they cannot be controlled and give
the cheese a bad flavor and a "gassy body." When a cheese is gassy, the
sides are most liable to be bulged and the body is full of gas holes or
pockets. Another defect is a sour cheese. This is caused by the
development of too much acid in the milk or during the manufacturing
process. A sour cheese usually cures slowly and has a pronounced sour
taste. The body is hard and bitter.
If the cheese contains too much moisture, it will cure rapidly and the
body will be very soft and pasty. In extreme cases it will be so soft
that it will run when the rind is broken. On the other hand if the
cheese does not contain sufficient moisture, it will cure very slowly
and the body will be hard and dry and sometimes crumbly. There is no
standard score-card for judging Limburger cheese. The Wisconsin
Cheese-makers Association[62] uses the following score-card for
Limburger:
Flavor 40
Texture 40
Color 10
Salt 5
Style 5
---
Total 100
+164. Yield and composition of Limburger.+--The yield of cheese depends
on: (1) the amount of fat and other solids in the milk from which it is
made; (2) the amount of moisture incorporated into cheese; (3) the loss
of solids during the manufacturing process.
The yield varies from 12 to 14 pounds of cheese from 100 pounds of milk.
The more fat and other solids in the milk, the more cheese can be made
from 100 pounds of the milk. The more moisture incorporated into the
cheese, the larger the yield. The quality of the cheese and the amount
of solids determine the amount of moisture that can be incorporated into
the cheese. The greater the losses during the manufacturing process, the
less is the yield. The composition of Limburger cheese is affected by
the same factors as the yield. The average cheese probably carries from
40 to 42 per cent of moisture. Limburger cheeses will vary in
composition from this analysis about as follows: water 38 to 44 percent,
protein 21 to 25 percent, fat 25 to 30 percent. The differences in
practice in factory groups are considerable. Certain markets call for
more solid brands, others for the very soft forms.
+165. Münster cheese+ originated in Germany near the city whose name it
bears. There is a limited demand for this variety in America; therefore
it is not extensively made. It is usually manufactured from whole milk
in a Limburger or Brick cheese factory. The process of manufacture is
between that of these two varieties in temperatures used, firmness of
curd and amount of moisture in the curd and cheese. The process is
probably more like that of Limburger. The curd is firmed more in the
whey than for Limburger, and more acid is developed. The cheeses are
pressed or drained in round forms 7 inches in diameter and 6 inches
high. The hoops are lined with cloth to prevent the loss of curd
particles while draining. When the cheeses are sufficiently drained,
until they are firm enough to hold their shape, the cloths are removed.
The cheese is salted by rubbing dry salt on the surface or soaking the
cheese in brine. The product is handled in the curing room very much the
same as Limburger or Brick cheese. When sufficiently ripe, each cheese
is wrapped in parchment paper and placed in a separate wooden box. This
cheese, when cured, has a characteristic flavor which is between that of
Limburger and Brick. The body is more or less open. The essential factor
in the manufacture of Münster cheese is clean milk. Bad fermentations,
such as produce gas and bad flavors, seriously interfere with the
manufacture and sale of the product. The cheese is usually made in the
late fall and winter, when it is difficult to manufacture Limburger.
CHAPTER X
SEMI-HARD CHEESES
Between the quickly perishable soft cheeses and the typical hard group,
are two series of varieties, one ripened by green mold and best known by
Roquefort, the other ripened by bacteria and typified by Brick cheese.
These cheeses are fairly firm, hold their shape well, ripen over a
period varying from a few weeks to several months and their marketable
period is comparatively long. In texture they are intermediate between
the conditions known as "soft" and "hard." In water-content, they range
at their best from 37 to 45 percent. Outside these limits, the cheeses
are often marketable but they lose in quality[63] and trueness to type.
+166. The green mold group.+--There are three well-known semi-hard
cheeses ripened by green or blue-green mold.[64] The mold is an
incidental factor in certain other forms but none of these forms has won
larger than local or purely national recognition. French Roquefort, on
the contrary, is probably the most widely known of all cheeses. Stilton,
to a small degree at least, has followed the English to the many lands
they inhabit. Gorgonzola, although made in Italy alone, has a large
market in other parts of Europe and in America. In the manipulations of
manufacture, these forms are not closely related but they resemble each
other in that each becomes streaked or marbled by the growth of green
mold (_Penicillium Roqueforti_) through open spaces within the cheese.
The "blue-veined" or marbled cheeses have a characteristic taste which
is developed in its most typical form in Roquefort.
+167. Roquefort cheese.+--This is a rennet cheese made from sheep's milk
(with occasional and minor admixture of goat's and cow's milk) in the
section of southern France centering about Roquefort in Aveyron. The
practices are standardized and controlled by a few companies, thus
reaching exceptional uniformity. Roquefort is uncolored, open, made from
firm but brittle or crumbly, not tough or waxy curd. Each cheese is
about 7¼ inches (20 cm.) in diameter and 3¼ inches (9 cm.) in
thickness without a definite rind, and when ripe enough for market is
scraped carefully, closely covered with tin-foil and kept in
refrigerators. The cut cheese shows extensive open spaces which are
lined with green mold. This cheese, in addition to a strong cheesy odor
and taste, has a peppery or burning quality which according to
Currie[65] is due to the formation of volatile fatty acids such as
caproic, caprylic and capric from the butter-fat of the sheep's milk
used. A series for Roquefort cheeses selected for excellent quality was
found by Dox[66] to show the following composition:
TABLE IV
COMPOSITION OF ROQUEFORT CHEESE
=========================================================
| WATER | FAT | PROTEIN | ASH | SALT
| PER | PER | PER | PER | PER
| CENT | CENT | CENT | CENT | CENT
--------------+--------+-------+---------+------+--------
Average | 38.69 | 32.31 | 21.39 | 6.14 | 4.14
Minimum | 37.49 | 31.50 | 19.14 | 5.18 | 3.64
Maximum | 40.10 | 33.53 | 23.06 | 6.81 | 4.88
=========================================================
The composition of the sheep's milk of the Roquefort producing region is
reported by Marre:[67]
TABLE V
COMPOSITION OF SHEEP'S MILK
=============================================================
| WATER | CASEIN | FAT | LACTOSE | ASH
| PER | PER | PER | PER | PER
| CENT | CENT | CENT | CENT | CENT
-------------+-------+--------+----------+---------+---------
Range | 76-83 | 5-8 | 5.5-10.5 | 4 to 5 | 0.8-1.2
Average | 79.5 | 6.5 | 8.0 | 4.5 | 1.0
=============================================================
The cheeses when properly made in the local factories are transported to
Roquefort for ripening in the famous caves which have made possible the
development of a great industry.
The Roquefort caves were originally natural openings leading back into
the face of a cliff until they reached a deep, narrow fault or crack in
the rock leading to the plains above. The cooler air from the plains
came down this crack over moist and dripping rocks and issued through
these clefts in a cold moisture-laden current which kept the caves about
50 to 55° F. and moist enough to ripen the cheeses without shrinkage. As
the business outgrew the natural caves, great cellars, some of them five
or six floors deep, were excavated and tunnels were dug back to the
crack so that the strong ventilating current reaches every part of the
cellars and keeps both temperature and relative humidity favorable to
the ripening of the cheeses.
+168. Cow's milk or Façons Roquefort.+--The supply of Roquefort is
automatically limited by the supply of sheep's milk. The sheep gives
milk only about five months in the year and at best a scant average of
about a pint a day to a sheep. Sheep's milk for cheese-making is not
produced, therefore, outside of very limited regions. Some cow's and
goat's milk unavoidably finds its way regularly into the industry
itself. Attempts were naturally made to substitute cow's milk. Outside
the controlled area, factories were established for this purpose. The
quality of the product did not equal that of the Roquefort factories,
and French courts decreed that the name Roquefort should not be used for
such products. Although some local success was obtained, not much
progress was made against the intrenched Roquefort industry. Similar
attempts to make such a product in Germany[68] were tried on an
extensive scale but failed. More recently, under the inspiration of
Conn, the United States Department of Agriculture and the Storrs
Experiment Station have studied the possibilities of such an industry.
Although the work is not completed, the preliminary reports[69] have
indicated the fundamental principles which must underlie such
development.
+169. Outline of making Roquefort.+--Some of the results of these
experiments are summarized in the following paragraphs:
_Milk._--Clean-flavored fresh milk testing 4-4.2 per cent fat and up to
2.8 per cent casein gives the best results. The milk with a high
percentage of cheese-making solids forms a firmer curd, hence works up
better in the process than milk of lower quality.
_Acidity._--The milk is ripened by lactic starter up to an acidity of
0.23 per cent titrated as lactic acid at the time rennet is added. This
gives a firm curd, which drains to the desired water-content but is low
enough to prevent the toughening effect of too high acid. A very slight
increase in initial acid--1 to 2 hundredths per cent--combined with the
rate at which acidity is developing introduces such physical changes in
texture as to make the final texture of Roquefort impossible.
_Temperature._--Rennet is added at or below 84° F. Every degree of heat
adds definitely to the efficiency of rennet. Below 82° F., curdling
becomes slower and the coagulum softer and more difficult to drain. The
sheep's milk curd is made from 76° to 84° F. but sheep's milk has about
twice the cheese solids found in cow's milk. It was found necessary to
raise the temperature as high as texture would permit. However, at 86°
F. the physical character of the curd tends to become tough or waxy in
handling. At 84° F. the curd remains brittle and crumbly. It was,
therefore, necessary to keep the curdling temperature down to 84° F.
_Renneting or setting._--Rennet at a rate of 3 to 4 ounces of standard
liquid rennet to 1000 pounds (10 to 12 c.c. to 100 pounds) was found to
give the best curd under experimental conditions.
_Curdling time._--One and one-half to two hours gave most satisfactory
results in forming curd. This should be very firm and stand until it
begins to "sweat," until beads of whey have begun to collect upon its
surface.
_Cutting._--The cow's milk curd gave best results when cut in two
directions with the half-inch curd knife. The resulting columns, a half
inch square in cross-section, may be handled without excessive losses.
_Draining._--The cut curd is dipped to a draining rack covered with
cloth with as little breaking as possible. During the draining process,
a certain amount of turning is necessary to facilitate the separation
and escape of the whey. If handled too much, losses of fat are increased
and the curd becomes tough or waxy instead of remaining brittle or
crumbly. When properly handled, not over 0.35 per cent of fat is lost.
Under favorable conditions, four-ninths to two-thirds of the original
weight of curd will separate and run off as whey in twenty to thirty
minutes. The curd meanwhile is exposed to the air of the room and cools
toward room temperature. If cooling goes too far, further drainage is
interfered with. Hence the curd is put into the hoop and the drainage
completed while the cheese is reaching its final form.
_Hoop._--Hoops for cow's milk Roquefort must be 7½ inches in diameter
and about 5¾ inches high to hold curd enough to produce a cheese the
size of the standard Roquefort when completely drained. Sheep's milk
with its higher percentage of solids does not require such high hoops.
The curd as it goes into the hoop should be a soft, pulpy mass with no
suggestion of toughness.
_Inoculation with mold._--The mold for Roquefort cheese (_Penicillium
Roqueforti_[70]) is readily grown in pure culture in ordinary loaves of
bread. For this purpose loaves hot from the oven are quickly drenched
with or immersed in hot paraffine to form an impervious crust to retain
moisture as well as to keep out contaminations. It is then allowed to
cool. The interior of each loaf is inoculated by drawing a suspension of
_P. Roqueforti_ spores in water into a sterile pipette (10 c.c.) which
is then thrust through the paraffined crust to the center of the loaf of
bread and allowed to empty there. The hole is sealed up with paraffine.
These loaves are incubated for about a month at room temperature. When
cut, every open space should be found lined with the green spores of the
mold. When dry enough, the mass may be powdered, and put into an
ordinary pepper box. When the curd is ready to go into the hoop, this
mold powder is sprinkled upon it from the pepper box.
_Handling._--Freshly made cheeses are turned within the first hour to
insure the proper smoothness of both sides. Further draining is best
accomplished in a room at about 64° F. with a relative humidity of 85 to
90 per cent. If the surface of the cheese becomes too dry, a rind is
formed. No real rind is permitted on Roquefort. If the temperature is
too high, slime forms quickly and unfavorable fermentation may occur.
Slime (bacteria and _Oidium lactis_ usually) must be scraped when it
becomes too heavy.
_Salting._[71]--Experimental cheeses were found to give the best results
when at the end of about three days' drainage they contained about 50
per cent water. Such cheeses were salted by sprinkling the entire
surface lightly, replaced upon the drain boards for one day, salted
again and piled in two's. After another day they received the third
salting and were piled in three's for two days longer. A total of about
10 per cent by weight of salt was used to secure an absorption of 4 per
cent. At the same time the water-content dropped to 40 to 43 per cent.
After salting is completed, the cheeses are brushed and punched with
holes to permit oxygen to enter.[72] They are then ready for ripening.
+170. Ripening of Roquefort.+--The ripening of experimental Roquefort
has required four to six months at a relative humidity of 85 to 90 per
cent. This relative humidity is just below the equilibrium relative
humidity of the cheese, hence permits a shrinkage of 2 to 4 per cent in
the water-content of the cheese. This makes it possible to control the
amount of surface slime developed.
If the relative humidity goes too high, the surface slime of bacteria
and yeasts becomes very heavy, soft and almost liquid, and follows the
openings into the cheese with resultant damage to appearance and flavor.
Even under the conditions at Roquefort, this slime must be removed by
rubbing or scraping several times to avoid injury to the cheeses,
together with the production of bad odor and taste. If the humidity
becomes too low, the surface becomes dry, hard and cracks open, the
friable crumbly texture is injured, and there is considerable loss in
weight. Salt forms about 4 per cent of the cheese. This is in solution
in the water present, which is about 40 per cent, and makes a brine of
about 10 per cent strength. This strength of brine does not prevent the
growth of the Roquefort mold (_Penicillium Roqueforti_) but does hinder
the development of _Oidium lactis_ in the open spaces within the cheese.
Accurate adjustment of temperature and relative humidity in the ripening
rooms to salt and water-content in the cheese is essential to proper
ripening. These conditions are furnished by the unique natural
conditions of the caves of Roquefort. The production of such cheeses
elsewhere depends either on the discovery of another locality with
closely similar conditions or on the artificial production and control
of the necessary temperature and relative humidity. This has been done
on an experimental basis by the use of cold storage apparatus combined
with proper humidifiers.
The differences between working with sheep's and with cow's milk lie in
the making process rather than in the ripening. Sheep's milk freshly
drawn shows a higher acidity than cow's milk, probably on account of the
acid reaction of its greater casein content. With nearly double the
total solids of cow's milk, the yield to one hundred pounds is much
greater, consequently the drainage of the curd is much more easily
handled.
Once made and salted, the cheeses require very nearly the same
conditions of ripening. The resultant products are alike in appearance
and texture. In flavor, cow's milk Roquefort differs in character from
sheep's milk cheese to such a degree as to be recognized by taste. The
difference was found by Currie[73] to be due to an actual difference in
the combination of fatty acids present.
Although these differences in character are recognizable by the expert
in testing the cheese, as well as by chemical analysis, cow's milk
Roquefort would satisfy that large proportion of consumers who use such
cheese only in connection with other fairly high flavored foods. The
demands for technical skill and factory equipment are not naturally
greater than for many other lines of cheese-making. The gradual
development of a cow's milk Roquefort may be anticipated.
[Illustration: FIG. 24.--Gorgonzola ripening establishment in valley
near Lecco.]
+171. Gorgonzola+[74] is a rennet cheese made from fresh whole cow's
milk, in northern Italy. It takes its name from the village of
Gorgonzola, a few miles from Milan, but the manufacture of the cheese
has spread over a wide area. The cheeses are made on farms and in
factories from which they are transported for ripening to cool valleys
of the Alps, principally near Lecco (Fig. 24). Boeggild introduced the
making of a cheese after the Gorgonzola process into Denmark about 1885.
This industry has been successful on a small scale since that time.
Gorgonzola cheeses are about 30 cm. (12 inches) in diameter and 18 cm.
(7 inches) thick and weigh 15 to 20 pounds. As exported they are usually
heavily coated[75] with a mixture usually barite, tallow and lard
colored with annatto or other cheese color. This coating prevents
shrinkage or mold on the surface of the cheese in transit. When cut
these cheeses vary greatly. All show marbling with mold (Roquefort
mold). During their ripening they become very slimy at the surface. To
open up air spaces for mold growth, this slime is scraped off and holes
are punched into the cheeses. These holes are readily seen in the final
product. Some show crumbly texture, well distributed mold, as in
Roquefort, with flavor approaching that cheese; in others the texture is
waxy rather than crumbly, a condition correlated regularly with
different character in the flavor. Frequently in whole areas or in small
pockets, slime consisting of bacteria and Oidium has followed the
openings into the cheese and affects its odor and taste.
Experimental Gorgonzola cheeses comparable with the Italian product were
made with cow's milk ripened as for Roquefort or higher, to 0.25-0.30
per cent (titrated as lactic acid), curdled at 86° F. (30° C.), cut into
cubes and slightly stirred, then dipped to a draining board for about
one-half hour, and put into the hoop. The cheeses drained quickly to
about 50 percent water and developed a surface rind as in the harder
cheeses. Cut surfaces showed a fairly open cheese in which mold grew
readily. These cheeses were salted to taste, not to a specified
percentage. They ripened with the same irregular results and the
characteristic range of flavors found in Gorgonzola. To avoid the
rotting of the cheese by surface growths, they were exposed to low
humidities for a time and cracks opened at the surfaces, as seen in the
ripening rooms at Lecco (Fig. 24). The texture was more or less waxy or
tough, which was correlated with the slightly higher heat at renneting
together with the stirring or "working" of the curd. Comparative
analyses of a series of imported cheeses confirm the interpretation that
the salt-content of Roquefort, 4 per cent approximately, prevents the
invasion of the interior of the cheese by Oidium. No complete study of
the ripening of Gorgonzola has been made. As far as followed, it
consists in an initial souring process followed by ripening by molds and
slime organisms. At its best, Gorgonzola is nearly equal to Roquefort
but the percentage of such quality is low. In spite of its irregular
quality, England has used larger amounts of Gorgonzola than of
Roquefort. Considerable quantities have been imported for the Italian
trade in the United States.
[Illustration: FIG. 25.--Gorgonzola cheese curing-room.]
+172. Stilton cheese+ bears the name of an English village[76] in which
it was first sold. It is made from cow's milk and is typically a whole
milk cheese, although part skim cheeses are regularly made and sold as
lower grades. In the Stilton-making counties, the milk from Shorthorn
cattle testing about 3.5 to 4.0 per cent fat is preferred to richer or
poorer grades. Such milk is curdled with rennet at about 86° F. in about
one hour; the curd is cut, dipped to a draining table covered with cloth
and drained slowly over a period of several hours, commonly overnight.
During this period considerable acidity is developed. The curd is then
milled or broken by hand, salted, packed into hoops 15 to 16 inches high
and 7 inches in diameter. These hoops are made from heavy tin (Fig. 26)
with four rows of holes about 3/10 inch in diameter. The freshly filled
hoops are allowed to stand and drain without pressure in a room at about
70° F. (Fig. 26). Such cheeses are turned every day for several days.
When solid enough to stand the hoops are removed, the cheeses are
scraped or rubbed with a knife until the surface is smooth, and commonly
wrapped with a cloth bandage to maintain the shape, if the cheese is
still too soft to stand firmly. In the factories, several rooms are used
with varying temperature and relative humidities, which makes it
possible to place each cheese under the condition best suited to its
texture and condition of ripeness. In general, the dairy sections of
England are much more humid than those of America and there are less
violent changes in temperature. Stilton cheese-making has grown up to
take advantage of this climatic factor in handling the product.
Transplantation of such an industry necessitates a mastery not only of
the manipulations but a grasp of the fundamental principles underlying
the process and a readjustment of practices to preserve those
principles.
[Illustration: FIG. 26.--Stilton cheeses in hoops, draining.]
Stilton is, then, a soured curd cheese in whose ripening a very
prominent part is played by the green mold (usually some strain of _P.
Roqueforti_) which grows throughout the cavities of its mass[77]. At
its best, it has attractive texture and flavor. Much of it fails to
reach high quality on account of the invasion of bacteria, _Oidium
lactis_, and very frequently myriads of cheese mites. The following
analysis was furnished as typical for ripe cheese by Miles Benson,[78]
late professor of dairying at Reading, England: Water 31 per cent, fat
36 per cent, casein 29 per cent, mineral constituents including salt
about 4 per cent. Approximately the same figures are given by Primrose
McConnell (Agricultural Note Book). The low percentage of salt is
another factor of uncertainty in the control of this Stilton product, as
in Gorgonzola, since these cheeses are commonly high in water-content at
first and are thus subject to invasion by Oidium.
Stilton has been made on a small scale in Canada[79] and occasionally
attempted in the United States. No serious effort to develop an industry
of commercial importance has been made in America. Comparative study of
the cheeses ripened by green mold tends to the conviction that the
adaptation of the Roquefort practice to the use of cow's milk offers a
more satisfactory basis for experiment than efforts to establish a
Stilton or a Gorgonzola industry.
+173. Gex.+--A cheese under this name made in southern France resembles,
in its general character as a ripened cheese, the English Stilton and
Italian Gorgonzola. Although it has no commercial importance, reference
is made to this cheese to show that mold-ripened cheeses have been
developed entirely independently in different countries to bring about
the same general character of product.
+174. Bacterially ripened series.+--The semi-hard cheeses ripened by
bacteria stand half-way between true Limburger and the hard forms. In
fact, brands of Limburger are readily found which approach the texture
and ripening of Brick cheese. In the same way, Brick cheeses are often
found which have the appearance, texture and much of the flavor of the
Cheddars with only a trace of the taste of Limburger. Port du Salut,
Oka, Münster, in France Livarot, in the Balkan regions Kascoval, belong
in this series.
+175. Brick cheese.+--The name of this cheese is probably due to the
finished product being about the size and shape of a brick. It is
similar to the German cheese Bäckstein and may have been developed from
it. It is typically a sweet-curd cheese, made from milk freshly drawn,
without permitting the development of appreciable quantities of acidity
until after the curd has been put into the hoop. In the making process,
it is intermediate between Limburger and the cheeses of the Cheddar
group. Some cheese-makers use an ordinary cheese vat, others a copper
kettle in manufacturing.
It is the usual practice to deliver the milk to the cheese factory both
morning and evening, without cooling. Cheese is made twice a day. In
some cases the milk is delivered only once a day, and extra precautions
must then be taken to care for the milk properly.
The discussion of the care of milk in Chapter II applies to that for
Brick cheese. For the best quality of cheese, the milk in the vat
should show about 0.15 of 1 per cent acidity and never above 0.18 of 1
per cent.[80]
+176. Making of Brick cheese.+[81]--The milk is received at the cheese
factory at a temperature of about 92° to 96° F. For the best results,
the acidity should be determined (by the acid test) to decide on the
amount of starter to use. Few Brick cheese-makers use an acid test or a
starter but these precautions would improve the product of many
factories. For method of using the acid test, see Chapter V. Chapter IV
discusses the preparation and use of starter. Usually 0.25 to 0.50 of 1
per cent of starter is the amount required. A small amount of starter is
used to aid the development of lactic acid and for the beneficial effect
it has on the flavor. A very small development of acid is desired after
adding the starter; therefore the change in acidity should be very
carefully watched with the acid test. The vat is usually set when the
acid test shows 0.16 of 1 per cent acidity. The more acid in the milk,
the less starter should be employed. Sufficient rennet extract should be
used to give a coagulation suitable for cutting in thirty to thirty-five
minutes. For method of adding the rennet extract, see Chapter V. When
the coagulum is firm enough for the curd to break clean over the finger,
it is ready to cut. The curd is cut with coarse knives into 3/8- or
½-inch cubes. After cutting, the curd is let stand three to five
minutes, then stirred with the hands for a few minutes until the whey
begins to separate and then stirred with the rake. Some makers do not
stir by hand but use the rake directly after cutting. When this is done,
great care must be exercised to stir the curd without breaking up the
pieces, because this causes a loss of fat. After cutting the curd is
stirred for twenty to thirty minutes before the steam is turned on. The
curd is heated very slowly at first and more rapidly during the last
stages of cooking. The curd is cooked to a temperature of 110° to 115°
F. The lower the temperature that can be used to produce firm curd, the
better the texture of the cheese. After cutting and during the cooking,
the curd must be constantly stirred so that lumps will not form. When
the curd forms lumps, the moisture is not evenly expelled. This results
in uneven texture and curing. Sometimes some salt is added to the curd
in the vat to restrain souring. The curd is stirred after cooking until
it is sufficiently firm. It remains usually in the whey for a total
period of one and one-fourth to one and one-half hours from the time of
cutting. It is then dipped into forms 10 inches long by 5 inches wide by
8 inches deep. The forms are without top or bottom and are placed on a
draining table. This table is so constructed that the whey can be saved
for stock feed. When ready to "dip," the whey is drawn down to the
surface of the curd in the vat, then the curd is dipped into the forms
or hoops. Care must be taken to get the same amount of curd into each
form to produce the cheeses of uniform size. Each cheese is turned
several times to insure even draining and even reduction of the
temperature. While draining, a follower is placed in each hoop and a
weight placed on each cheese. Usually a brick is used for this weight. A
cheese is allowed to drain or press for ten to fifteen hours. It is
then placed on the salting table and rubbed with coarse salt. While on
the salting table, a cheese is placed on its broad side. Some
cheese-makers prefer to salt their cheeses by soaking them in a salt
brine. This brine should be strong enough to float an egg. Salting
requires three days. The cheeses are then brushed free from excess salt
and taken to the cellar to cure or ripen.
+177. Ripening Brick cheese.+--For this process, the cellars are kept at
about 90 percent relative humidity and a temperature of 60° to 65° F.
Some prefer a temperature for curing as high as 68° F. During the
curing, the surfaces of the cheese are kept moist and mold growths kept
down by rubbing or brushing the cheese with pure water or salt and
water. In the curing cellars the cheeses are placed on shelves; at first
they are set close together and as they cure, they are separated. During
curing, the color changes from a whitish to a reddish brown. The cheese
cures from the outside toward the center. When first made, the product
is harsh and hard in texture but during the ripening process it becomes
mellow and smooth. The cheeses remain on the curing shelves for four to
six weeks, after which they are wrapped in heavy waxed paper and boxed.
A cheese ready for market usually weighs about five pounds. A Brick
cheese box is 5 inches deep by 20 inches wide by 3 feet long, and holds
110 to 115 pounds of cheese.
+178. Qualities of Brick cheese.+--The cheeses should be neat and
attractive and the rind not cracked or broken. The sides should be
square and not bulged. The cheese should have a clean, characteristic
Brick cheese flavor. The body and texture should be mellow and smooth
and when rubbed between the thumb and forefinger, should break down
like cold butter. The color should be uniform. The cheese should contain
the proper amount of salt and moisture. One of the worst faults with
Brick cheese is bad flavor. This is many times due to the cheese-maker
not using clean flavored starter. It may also be due to bad flavored
milk. A Brick cheese-maker has no means of controlling gassy
fermentations. These show themselves in the bad flavor of the cheese and
in the porous body. They also cause the cheese to bulge. If detected,
gassy milk should be rejected. If too much acid is developed, a sour
cheese is the result. This will not cure normally and usually has a sour
flavor. The body will be brittle and mealy. If too much salt is used,
the cheese may have a salty taste and it will cure very slowly. If not
enough salt is used, the cheese may cure too rapidly and undesirable
flavors and fermentations develop. The cheese must have the proper
moisture-content; if too much moisture is present, the cheese cures too
fast and is soft and pasty in body; if not enough moisture, then the
reverse is true. Tabulation of cheeses of special quality, as submitted
in scoring contests, show an average water-content of 37 to 38 per cent,
with occasional cheeses verging toward Limburger in texture and flavor
with 40 to 42 per cent water, and others indistinguishable from Cheddar,
with water-content as low as 34 per cent.
The Wisconsin Cheese-makers Association uses the following score-card
for the judging of Brick cheese on a scale of 100:
Flavor 40
Texture 40
Color 10
Salt 5
Style 5
---
100
+179. Composition and yield.+--The composition of Brick cheese varies
within wide limits. The average cheese probably contains from 37 to 39
per cent of water, although many cheeses are above and below this
average; Doane and Lawson[82] give the fat as 28.86 per cent, proteins
23.8 per cent and total ash 4.20 per cent.
The composition and yield are both affected by: (1) the moisture-content
of the cheese; (2) composition of the milk from which made; and (3)
losses during the manufacturing process. The average yield of Brick
cheese is 11 to 13 pounds to 100 pounds of milk.
+180. Port du Salut cheese.+--The Trappist monks originated this type of
cheese in their monasteries in France. Under the name of their community
Oka, it has been made and sold widely by the Trappist Fathers of Quebec.
In recent years, factories independent of the order have made such
cheese both in America and in Europe.
The following outline of the making process indicates the close
relationship between Port du Salut and Brick cheeses. Whole milk or milk
not over one-fifth skimmed is ripened to medium acidity, then heated to
90° to 95° F. according to season and acidity. Rennet enough is added
(see Chapter V) to curdle in thirty to forty minutes, although some
makers shorten the time to twenty minutes. When formed, the curd is cut
into small cubes and excess of whey is dipped away. The constantly
stirred mass is then heated or cooked to 100° to 105° F. within a period
of ten to twelve minutes or according to some makers twenty to thirty
minutes. It is allowed to stand a few minutes to settle. Most of the
whey is then drawn and the mass is stirred vigorously to prevent fusion
of the curd granules. The curd is ready for the hoop when the particles
are about the size of grains of wheat and do not stick together when
squeezed with the hand. The individual grains of curd should crumble
easily between the fingers. The hot curd is transferred directly to the
hoops without cooling. For this purpose, a hoop is set upon the table
covered with a cloth and the curd dipped into the cloth. The edges of
the cloth are then folded over. In this condition the cheese is
transferred to the press where gradually increasing pressure begins with
3 to 4 pounds and reaches about 70 pounds. To insure proper shape,
cheeses are turned and put into fresh cloths at the end of the first
hour and turned subsequently several times during the pressing period of
about twelve hours.[83]
Port du Salut cheeses are salted by rubbing fine salt on the surface by
hand at the rate of 1.2 to 2 per cent of the weight of the cheese. After
about two days in the salting process, they are put into the ripening
cellars. The cellars are wet, since they reach 90 to 95 per cent
relative humidity at a temperature of about 55° F. After two days in the
cellar, the cheeses are plunged into a tank of saturated brine to which
a trace of cheese color has been added. As they come out of these tanks,
they are yellowish and greasy or slimy. They are returned to the
shelves where they are rubbed every day with a cloth or by hands wet in
brine. After about one week they are again plunged in the brine.
Treatment with brine tends to insure a firm rind. The cheeses are rubbed
more or less regularly with brine through the whole ripening period.
After six weeks, such cheese may be eaten. The cut surface of Port du
Salut is creamy in color, may or may not show small holes. In texture it
is soft enough to spread readily under pressure without losing its shape
in handling. In flavor the cheese is a mild form belonging to the
Limburger group.
Port du Salut cheeses as imported from France usually are firm round
cakes about 1½ inches thick, weighing about 3 pounds.
CHAPTER XI
_THE HARD CHEESES_
The hard cheeses form a great series of groups, whose most prominent
physical character is their firm or hard texture. This is correlated
with comparatively low water-content, which is usually between 30 and 40
per cent. Although certain varieties occasionally test above 40 per cent
water, this deviation is accompanied by quick ripening and rapid
spoilage. These varieties of cheese are staple products with long
marketable periods; therefore they may be handled in large lots,
shipped, carted and stored freely without the losses such treatment
would entail in soft cheese. The retailer frequently buys hard cheese by
the ton, not by the cheese or by the box.
In making, these varieties are characterized as cooked and pressed
cheeses. Although both the heating of a curd and the pressing of a newly
made cheese occur among semi-hard forms, these practices appear in their
most typical forms in the hard cheeses.
The hard cheeses show two types of texture. A cut cheese may appear
smooth, free from holes or with a few angular cracks or seams, or it may
show round holes or "eyes." In the smooth textured forms every effort is
made to prevent gassy fermentations, usually by controlling the
fermentation of the curd in the making process. When "eyes" are present,
the end sought has been a development of a particular form of gassy
fermentation which gives this appearance and brings about the
characteristic ripening texture and flavor.
The hard cheeses have been developed in groups of national varieties.
The best known of these groups are those which may be represented by
English Cheddar, American Factory Cheddar, Danish, the Edam of Holland,
Swiss and Parmesan with many related varieties in Italy and neighboring
countries of southern Europe.
+181. The Danish group.+--The Danish cheeses are related in appearance
and flavor to the English group represented by Cheddar. The demand for
butter in Europe has been so great that the Danish cheese-makers have
developed skim and part skim varieties largely to the exclusion of the
whole milk form. Skillful handling of their process has resulted in a
product which has had a very large and appreciative market in England
and Germany.
+182. The Dutch group.+--Edam and Gouda are the two forms of cheese made
in Holland and most widely known among other peoples. Both reach America
in considerable quantities; both are shipped in large amounts to
tropical countries. Although attempts have been made to manufacture them
in America, no commercial production of these cheeses has been
successful. Although whole milk grades of these cheeses are known, they
are to a large measure part skim in manufacture. The presence of one or
both of these forms in every large market in America makes the general
facts of their production of general interest. Parts of a report on
experimental work in the making of Edam and Gouda are, therefore, given
here.
+183. Edam cheese+[84] is a sweet-curd type, made from partially
skimmed-milk. It comes to the market in the form of round red balls,
each weighing from 3½ to 4 pounds when cured. It is largely
manufactured in northern Holland and derives its name from a town famous
as a market for this kind of cheese.[85] Milk from which one-fourth to
one-third of the fat has been removed is used. Too great pains cannot be
taken in regard to the condition of the milk. It should be fresh, free
from every trace of taint; in brief, it should be in as perfect
condition as possible.
+184. Method of manufacture.+--The following paragraphs give the steps
in the manufacture of Edam cheese:
_Treatment of milk before adding rennet._--The temperature of the milk
should be brought up to a point not below 85° F. nor much above 88° F.
When the desired temperature has become constant, the coloring matter
should be added. Cheese color is used at the rate of 1½ to 2 ounces
for 1000 pounds of milk. The coloring matter should, of course, be added
to the milk and thoroughly incorporated by stirring before the rennet is
added.
_Addition of rennet to milk._--The rennet should not be added until the
milk has reached the desired temperature (85° to 88° F.) and this
temperature has become constant.
When the temperature reaches the desired point and remains there
stationary, the rennet extract is added. Rennet extract may be used,
4½ to 5½ ounces being taken for 1000 pounds of milk, or enough to
coagulate the milk in the desired time, at the actual temperature used.
The milk should be completely coagulated, ready for cutting, in about
twelve to eighteen minutes from the time the rennet is added. The same
precaution observed in making Cheddar cheese should be followed in
making Edam cheese with reference to care in adding the rennet, such as
careful, accurate measurement, dilution with pure water before addition
to milk.
_Cutting the curd for Edam._--When the curd breaks clean across the
finger, it should be cut; it is cut a very little softer than in the
Cheddar process as ordinarily practiced. As stated, this stage of
hardness in the curd which fits it for cutting should come in twelve to
eighteen minutes after the rennet is added. First, a vertical knife is
used and the curd is cut lengthwise, after which it is allowed to stand
until the slices of curd begin to show the separation of whey. Then the
vertical knife is used in cutting crosswise, after which the horizontal
knife is at once used. Any curd adhering to the bottom and sides of the
vat is carefully removed by the hand, after which the curd-knife is
again passed through the mass of curd lengthwise and crosswise,
continuing the cutting until the curd has been cut as uniformly as
possible into very small pieces.
_Treatment of Edam curd after cutting._--When the cutting is completed,
one commences at once to heat the curd up to the temperature of 93° to
96° F. The heating is done as quickly as possible. While the heating is
in progress, the curd is kept constantly agitated to prevent settling
and consequent overheating. As soon as the curd shows signs of
hardening, which the experience of the worker will enable him to
determine, the whey is drawn off until the upper surface of the curd
appears, when one should commence to fill the press molds.
[Illustration: FIG. 27.--Edam cheese mold.]
_Filling molds, pressing and dressing Edam._--The molds, which are
described later in detail, are well soaked in warm water previous to
use, in order to prevent too sudden chilling of curd and consequent
checking of separation of whey. As soon as whey is drawn off, as
indicated above, one begins to fill the pressing molds (Fig. 27). The
filling should be done as rapidly as possible to prevent too great
cooling of curd. When the curd has been put into the molds, its
temperature should not be below 88° F. Unless care is taken to keep the
curd covered, the portion that is last put into the molds may become too
much cooled. In making Edam cheese on a small scale, it is a good plan
to squeeze the moisture out with the hands as much as possible and then
break it up again before putting in the molds, when the curd should be
pressed into the mold firmly by the hands. The molds should be filled as
nearly alike as possible. The cheese should weigh from 5 to 5¼ pounds
each when ready for the press. When the filling of molds is completed,
they are put under continual pressure of 20 to 25 pounds for about
twenty-five or thirty minutes. While the cheese is being pressed, some
sweet whey is heated to a temperature of 125° or 130° F., and this whey
should not be allowed to go below 120° F. at any time while it is being
used. When the cheeses are taken from their molds, each is put into the
warm whey for two minutes, then removed and dressed. For dressing Edam
cheese, the ordinary cheese bandage cloth is used. This is cut into
strips, which should be long enough to reach entirely around the cheese
and overlap an inch or so, and which should be wide enough to cover all
but a small portion of the ends of the cheese when put in place. Before
putting on the bandage, all rough projections should be carefully pared
from the cheese. In putting on, the cheese is held in one hand and the
bandage is wrapped carefully around the cheese, so that the whole is
covered, except a small portion on the upper and lower surface of the
cheese. These bare spots are covered by small pieces of bandage cloth of
a size sufficient to fill the bare surface. The bandage is kept wet with
the warm sweet whey, thus facilitating the process of dressing. After
each cheese is dressed, it should be replaced in the dressing mold, care
being taken that the bandage remains in place and leaves no portion of
the surface of the cheese uncovered and in direct contact with the mold.
The cheese is then put under continual pressure of 60 to 120 pounds and
kept for six to twelve hours.
+185. Salting and curing Edam.+--There are two methods which may be
employed in salting,--dry and wet. In dry-salting, when the cheese is
finally taken from the press, it is removed from the press mold, its
bandage is removed completely, and the cheese placed in another mold,
quite similar, known as the salting mold. Each cheese is placed in a
salting mold with a coating of fine salt completely surrounding it. The
cheese is salted in this way once each day for five or six days. Each
day the cheese should be turned when it is replaced in the mold, so that
it will not be rounded on one end more than the other.
In the method of wet-salting, the cheese is placed in a tank of salt
brine, made by dissolving common salt in water in the proportion of
about 1 pound of salt to 2½ quarts of water. Each cheese is turned
once a day and should be left in the brine seven or eight days. When
the cheese is taken from the salting mold or salt bath, it is placed in
warm water and given a vigorous, thorough brushing in order to remove
all slimy or greasy substances that may have accumulated on the outer
surface. When the surface is well cleansed, the cheese is carefully
wiped dry with a linen towel and placed upon a shelf in the curing-room.
In being put on the shelves, the cheeses should be placed in contact so
as to support one another, until they have flattened out at both ends so
much that they can stand upright alone. Then they are moved far enough
apart to allow a little air space between them. Another method of
securing the flattened ends is to support each cheese on opposite sides
by wedge-shaped pieces of wood. After being placed on the shelves in the
curing-room, they are turned once a day and rubbed with the bare hand
during the first month, twice a week during the second month and once a
week after that. When any slimy substance appears on the surface of the
cheese, it should be washed off at once with warm water or sweet whey.
The special conditions of the curing-room will be noticed in detail
below. When the cheeses are about two months old, they can be prepared
for market in the following manner: They are first made smooth on the
surface by being turned in a lathe or in some other manner, after which
the surface is colored. For coloring, some carmine is dissolved in
alcohol or ammonia to secure the proper shade, and in this color-bath
the cheeses are placed for about one minute, when they are removed and
allowed to drain, and as soon as they are dry the outside of each cheese
is rubbed with boiled linseed oil, in order to prevent checking. They
are then wrapped in tin-foil, which is done very much like the
bandaging. Care must be taken to put on the tin-foil so that it presents
a smooth, neat appearance. The cheeses are finally packed in boxes,
containing twelve cheeses in each box, arranged in two layers of six
each with a separate partition for each cheese.
+186. Equipment for making Edam cheese.+--Careful attention must be
given to the moisture and temperature of the curing-room. This room
should be well ventilated, quite moist and its temperature kept between
50° and 65° F. These are conditions not easy to secure in any ordinary
room. Some form of cellar is best adapted for these conditions. The
amount of moisture can be determined by an instrument known as a
hygrometer. In a curing-room suited for Edam cheese, the moisture should
be between 85 and 95 per cent, or a little short of saturation. When the
temperature is between 50° and 65° F., the moisture is between 85 and 95
per cent if the wet-bulb thermometer is from 1 to 2° F. (or ½ to 1°
C.) below the dry-bulb thermometer. Cheese will check or crack and be
spoiled for market, if the degree of moisture is not kept high enough.
Aside from the molds, press and salting vat, the same apparatus that is
used in making Cheddar can be used for Edam cheese. The pressing mold is
turned preferably from white wood or, in any case, from wood that will
not taint. Each mold consists of two parts; the lower constitutes the
main part of the mold, the upper portion is simply a cover. The lower
portion or body of the mold has several holes in the bottom, from which
the whey flows when the cheese is pressed. Care must be taken to prevent
these holes being stopped up by curd. This part of the mold is about six
inches deep and six inches in diameter across the top. The salting mold
has no cover and the bottom is provided with only one hole for the
out-flow of whey; in other respects it is much like the pressing mold.
+187. Qualities and yield of Edam cheese.+--The flavor of a perfect Edam
cheese is difficult to describe. It is mild, clean, and pleasantly
saline. In imperfect Edams, the flavor is more or less sour and
offensive. In body, a perfect Edam cheese is solid, rather dry and mealy
or crumbly. In texture, it should be close and free from pores. In the
experiments here reported the amount of fat in 100 pounds of the
partially skimmed-milk varied from 2.45 to 3.20 pounds and averaged 2.77
pounds. Of this amount, from 0.30 to 0.51 pound of fat was lost in the
whey, with an average of 0.39 pound. The yield of cheese from 100 pounds
of milk varied from 9.60 to 11.82 pounds and averaged 10.56 pounds.
+188. Gouda cheese.+[86]--This Dutch variety is a sweet-curd cheese made
from whole milk. In shape, the Gouda cheese is somewhat like a Cheddar
with the sharp edges rounded off and sloping toward the outer
circumference at the middle from the end faces. They usually weigh 10 or
12 pounds, though they vary in weight from 8 to 16 pounds. They are
largely manufactured in southern Holland, and derive their name from the
town in which they were first made. Fresh sweet milk that has been
produced and cared for in the best possible manner should be used.
+189. Method of manufacture.+--The processes of manufacturing Gouda
cheese are as follows:
_Treatment of milk before adding rennet._--The temperature of the milk
should be brought up to a point not below 88° F. nor much above 90° F.
When the desired temperature has been reached and has become constant,
the coloring matter is added. One ounce of cheese color for about 1200
pounds of milk may be used. The coloring matter should be thoroughly
incorporated by stirring before the rennet is added.
_Addition of rennet to milk._--The rennet should not be added until the
milk has reached the desired temperature (88 to 90° F.) and this
temperature has become constant. The milk should be completely
coagulated, ready for cutting, in fifteen or twenty minutes. The same
precautions should be used in adding rennet as those previously
mentioned in connection with the manufacture of Edam cheese.
_Cutting the curd._--The curd should be cut when it is of about the
hardness generally observed for cutting in the Cheddar process. The
cutting is done as in the Cheddar process except that the curd is cut a
little finer in the Gouda cheese. Curd should be about the size of peas
or wheat kernels when ready for press and as uniform in size as
possible.
_Treatment of curd after cutting._--After the cutting is completed,
heating and stirring is begun at once. The heating and constant stirring
is continued until the curd reaches a temperature of 104° F., which
should require from thirty to forty minutes. When the curd becomes
rubber-like in feeling, the whey should be run off. The whey should be
entirely sweet when it is removed.
_Pressing and dressing Gouda._--After the whey is off, the curd is put
in molds at once without salting (Fig. 28). Pains should be taken in
this process to keep the temperature of the curd as near 100° F. as
possible. Each cheese is placed under continuous pressure amounting to
ten or twenty times its own weight and kept for about half an hour. The
first bandage is put on in very much the same manner as in Edam cheese
making. The cheese is then put in press again for about one hour. The
first bandage is then taken off and a second one like the first put on
with great care, taking pains to make the bandage smooth, capping the
ends as before. The cheese is then put in press again and left twelve
hours or more.
[Illustration: FIG. 28.--Gouda cheese mold.]
_Salting and curing._--When Gouda cheese is taken from the press, the
bandage is removed and it is placed for twenty-four hours in a
curing-room like that used for Edam cheese, as previously described.
Each cheese is then rubbed all over with dry salt until the salt begins
to dissolve, and this same treatment is continued twice a day for ten
days. At the end of that time, each cheese is carefully and thoroughly
washed in warm water and dried with a clean linen towel. The cheeses are
then placed on the shelves of the curing-room, turned once a day and
rubbed. The temperature and moisture are controlled as described in the
curing process of Edam cheese. If the outer surfaces of the cheese
become slimy at any time, they are carefully washed in warm water and
dried with clean towels. Under these conditions, cheese ripens in two or
three months.
+190. Equipment for Gouda cheese.+--The molds, press and curing-room
are the only equipment needed in the making of Gouda cheese that differ
from that employed in making Cheddar cheese. The mold used for Gouda
cheese consists of two portions, which are shown separately in Fig. 28.
These molds are made of heavy pressed tin. The inside diameter at the
middle is about 10 inches, that of the ends about 6½ inches. The
height of the mold is about 5½ inches, and this represents the
thickness of the cheese, but by pushing the upper down into the lower
portion, the thickness can be decreased as desired.
+191. Composition and yield of Gouda.+--In work with milk averaging 4.2
per cent of fat there were lost in the whey from 0.29 to 0.43 per cent
with an average of 0.35 per cent of fat. The loss of fat appears to be
not much greater than the average loss met with in cheese factories in
making Cheddar cheese. From 100 pounds of milk, there were made from
11.60 to 13.35 pounds of green cheese, with an average of 12.50 pounds.
The percentage of water in the experimental cheese varied from 41.25 to
45.43 per cent and averaged 43.50 per cent.
CHAPTER XII
_CHEDDAR CHEESE-MAKING_
Cheddar is the best known cheese throughout the United States and the
one most commonly made in factories. The Cheddar process was brought to
America by English immigrants. Similar to Cheddar cheese are Pineapple,
English Dairy, Sage cheese, skimmed-milk and California Jack cheese made
in this country, and Derbyshire, Leicestershire, Wensleydale and
Cheshire made in England. The Cheddar cheese process as employed in the
factories to-day has been modified and improved since it was first
introduced into this country by the early immigrants. The following
description[87] includes only the practices as found in the factories
to-day if whole milk is used. Skimmed-milk Cheddar cheese is discussed
later.
+192. The lot-card.+--The Cheddar process involves several hours of
manipulation and includes many details which should be closely and
accurately observed and recorded. The necessity of carrying observations
of several different factors at the same time makes a scheme of
recording data essential to convenient work. For this purpose, a
lot-card for Cheddar cheese is introduced here and the pages given to
particular factors are indicated in the space intended for the recording
of observations. The manufacture of Cheddar cheese is a complicated
process, because several factors must be given attention at the same
time. A careful record of the observations of each step in the
successive handling of each lot of milk puts the operator in possession
of a permanent record of his experience. This record has several uses.
It may help to convince patrons of the importance of eliminating faults
in the milk; it furnishes the cheese-maker a cumulative record of his
experiences in handling milk with special qualities, such as high or low
fat-content, over-acidity or taints. Since Cheddar ripening covers a
period of weeks and months, no operator can remember particular lots of
milk sufficiently well to be able to use his experience on the
interpretation of the qualities found in the ripened product.
[Illustration: FIG. 29.--Delivering milk to the cheese factory.]
+193. The milk.+--It is the usual practice to deliver the milk to the
cheese factory each morning (Fig. 29). The night's milk is cooled and
kept clean and cold until delivered at the factory. It is advisable not
to mix the cold night's milk and the warm morning's milk, but to deliver
them in separate cans to the cheese factory at the same time. The milk
is weighed, sample for fat test taken and then run into the vat (Fig.
30). The receiving or taking in of the milk is one of the most important
parts of the cheese factory work. It is practically as important as the
actual manufacturing of the cheese.
+21 CHEESE.+ This card must remain with lot ........... from the milk room
until the finished product is ready to leave the building, then it should
be handed to instructor.
+MAKING+ Day and Date ................................ Vat ...............
+Milk | |
Used+ | | +Milk+
........................|............| Appearance of Milk ................
........................|............| Odor ..............................
........................|............| Taste .............................
Total pounds |............| Weather conditions ................
------------------------+------------+------------------------------------
...........% fat ...........lbs. fat | +Starter+
| Kind used..........................
....% solids not fat ....lbs. s.n.f. | Flavor.............................
| Acidity............................
....% casein ....lbs. casein. | Amount used.......... % used.......
-------------------------------------+------------------------------------
+Time of Minutes+ | +% Acid+ | +Temperature+
adding starter }...... | _In Milk_ | of milk when received
} | | when starter added...
adding rennet }...... | when received............| when rennet added....
} | before adding starter....| when whey removed....
coagulation }...... | after adding starter.....| at pressing..........
} | when rennet added........+----------------------
cutting }...... | | +Rennet Test+
} | | when milk received...
turn'g on steam }...... | _In Whey_ | after adding starter.
} | after curd is cut....... | when rennet added....
turn'g off steam}...... | at dipping.............. +----------------------
} | at packing.............. | +Hot Iron Test+
dipping }...... | at milling | at dipping...........
} | at milling | at packing...........
packing }...... | at salting | at salting...........
} +--------------------------+----------------------
milling }...... | +Condition of Curd+
} |
salting }...... | when cut........................................
} | when packed.....................................
hooping }...... | when milled.....................................
} | when salted.....................................
pressing }...... | when pressed....................................
} +-------------------------------------------------
dressing }...... | Amount per | +Color+ | +Rennet+ | +Salt+
| 1000 lbs. milk |.........|..........|........
Total time from }....| | | |
setting to pressing} | Total Amount |.........|..........|........
------------------------+-------+-----------+---------+----------+--------
% fat in lbs. fat estimated | If comments are added on
.......whey ....... so lost. | reverse side, put cross here............
% of total milk | Work and
....fat lost in whey | Observations by.........................
Assisted by...............................................................
--------------------------------------------------------------------------
+YIELD+ Day and Date......................... Time.......................
Serial
Weight of cheese when removed from press to curing room,......lbs. No....
lbs. milk for Kind of cheese made lbs. cheese per
..........one lb. cheese. ................... ......100 lbs. milk
lbs. cheese for one No. of cheese made. lbs. cheese for one
..........lb. fat in milk. ................... ....lb. total solid
If comments are added on reverse side put cross here...........
Work and observations by..................................................
--------------------------------------------------------------------------
Arranged by W. W. Hall.
[Illustration: FIG. 30.--Receiving, sampling, weighing and running the
milk into the cheese vat.]
Any milk high in acid or with a bad flavor should be avoided. It is
often bad policy to reject the milk, for a neighboring factory will
accept it and the factory not only loses the milk but also the patron.
Factories should have an agreement to prevent this. The acidity can be
determined by the acid test, but the detection of flavors must be made
by the cheese-maker himself with the aid of smell and taste. Many of
the bad flavors in the cheese can be traced to the poor quality of the
milk. One of the worst qualities in milk and cheese is the presence of
gas-producing organisms.[88] Any milk which shows gassy fermentation
should be rejected, for it is difficult to make cheese from this and at
best there will be a large loss during the manufacturing process. The
cheese may have a bad flavor and develop "pin-holes" and in extreme
cases may puff up like a ball. The person receiving the milk should talk
to the farmers or dairy-men about the proper care of the utensils and
milk. He must see that the cans are kept clean. One very bad practice is
to deliver milk and take home whey in the same cans. The cans, as they
are brought back from the cheese factory full of whey, are often left in
the barn or near a hog-pen until the whey is fed. Unless such cans are
emptied immediately on returning to the farm and then rinsed out with
cold water, thoroughly washed and scalded, bad flavors may develop in
the cheese. It is thought that this causes "fruity" or sweet flavor,
which resembles that of fruits such as raspberries, strawberries or
pineapples.
+194. Ripening the milk.+--A slight development of acidity is required:
(_a_) to obtain the formation of a firm curd; and (_b_) to establish
immediate dominance of a desirable type of lactic organism which will
produce the large amount of acid required later in the cheddaring
process. The development of this acidification before the addition of
rennet is known as the ripening of the milk. The extent of ripening
advised by different schools of makers has varied from an acidity of
0.20 of 1 per cent or even slightly higher percentage titrated as lactic
acid, to about 0.17 of 1 per cent as now preferred by some of the most
successful groups of workers. The ripeness of the milk can also be
determined by the use of the rennet test.
The milk may be ripened by allowing the lactic organisms already present
in the milk to develop naturally. This requires considerable time and
while the lactic acid-forming bacteria are developing, other and
undesirable fermentations may be taking place, so that the good results
which should follow the uninterrupted development of the lactic
acid-forming organisms are lost. Starter is commonly used to produce the
desired ripening of the milk. (For the preparation of starter see
Chapter IV.)
[Illustration: FIG. 31.--Steel cheese vat.]
Some makers put the starter into the empty vat (Fig. 31) and add the
milk as it is received; others add it to the total volume of cold milk
and then begin to heat it. Whenever the starter is used, it should be
strained to remove lumps. These lumps might cause a mottled color in the
cheese. The best practice calls for an acidity or a rennet test of the
mixed milk after it has been brought to the setting temperature in the
vat. With milk tested at this stage and the volume of milk in the vat
known, the cheese-maker is able to calculate closely the amount of
starter needed. When the quantity of starter to use is in doubt, the
amount added should be under rather than over the estimate, since the
need of more can be determined by making frequent rennet and acid tests
in a very few minutes without damage to the cheese. If too much starter
has been used, acid or sour cheese is usually obtained, with loss in
market quality.
An over-development of acidity at any stage of the manufacturing process
affects the flavor, body and texture, color and finish of the cheese.
The product is known as a sour cheese, and can usually be identified by
its sour taste and smell. A sour cheese while curing will seldom develop
a normal Cheddar flavor and the texture will be hard and harsh and very
brittle. The body will not be smooth but harsh and grainy. The
over-development of acid will show by fading or bleaching the color. A
sour cheese usually leaks whey for a few days after being placed on the
curing-room shelves.
Ripening the milk is one of the most important parts of cheese-making.
Proper ripening places the acid fermentations under the control of the
cheese-maker so that he may know what results will follow his labors.
The operator can control the acidity while ripening the milk, but after
the rennet is added all control of the acidity is lost. From that time,
the moisture must be regulated in proportion to the acidity.
Before setting, the milk should be ripened to such a point as to leave
at least two and one-half hours from the time that the rennet extract is
added until the acid development has reached the stage at which it is
necessary to remove the whey. By the acid test the milk may vary from
0.16 to 0.18 of 1 per cent, but no definite statement can be given for
the rennet test. This can be determined only by comparison from day to
day. For operation of rennet test see Chapter V. During this period of
two and one-half hours, the curd is formed, then cut, and the
temperature is raised from 84° or 86° F. (the temperature at which the
rennet extract is added) to about 98° to 100° F. The curd must be kept
agitated so that the particles will not mat together; this is necessary
to obtain sufficient contraction of the particles of curd with the
proper reduction of water-content. If the milk becomes too ripe (too
sour) before the rennet is added, there will not be sufficient time for
these steps to take place naturally. In such cases special means are
required to firm the curd. These result in a loss of both quality and
quantity of cheese. On the other hand, if the milk is not ripened, but
the rennet extract added, regardless of the acid development, one of the
important natural forces for expelling the moisture is lost. The time
required for the particles of curd to contract is much prolonged, the
expulsion of whey is usually inadequate and the curd remains in a soft
or wet condition. Using too much starter is almost equally bad, for
although it hastens the making process, it produces a sour or acid
cheese.
+195. Setting or coagulating.+--The milk for Cheddar cheese-making is
heated to 86° to 88° F. or occasionally a slightly lower temperature.
This temperature is found by experiment to give the texture of curd most
favorable for the desired results. Although some cheese-makers work as
low as 84° F., the texture of such curd is too soft and coagulates too
slowly. The very slight change of 2° F. produces curd which coagulates
more quickly and is tougher and firmer.
If the cheeses are to be colored, the color should be added after all
the starter. It should be thoroughly and evenly mixed with the milk to
insure an even color in the cheese. If the color is added before the
starter, there are likely to be white specks in the cheese, on account
of the coagulated casein in the starter. The amount of color to use
depends on the tint desired in the cheese. It varies from 1/3 to ½
ounce to 1000 pounds of milk for a light straw color to 1½ to 2
ounces for 1000 pounds of milk for a deep red color.
Enough rennet should be used to produce a curd firm enough to cut in
twenty-five to thirty-five minutes. The necessary amount will vary with
the strength of the rennet extract itself, with the acidity, the
temperature, the nature of the lot of milk, and with the individual aims
of the maker in which he adjusts the other factors to his preferences as
to rapidity of rennet action. With the usual commercial extract, the
needed amount ranges from 2.5 to 4 ounces for 1000 pounds of milk. As
for all varieties of cheese, the rennet extract should be diluted in
cold water at about one part rennet to forty parts water and thoroughly
stirred into the milk. (See Chapter V.)
+196. Cutting.+--The object of cutting is to obtain an even expulsion of
the moisture from the curd. The curd is cut as soon as it becomes firm
enough. To determine this, various tests may be used. Some operators
test it by pressing it away from the side of the vat, considering it
ready to cut when it separates cleanly from the metal. The test most
commonly used is to insert the index finger obliquely into the curd,
then to start to split the curd with the thumb and finally to raise the
finger gently; if ready to cut, the curd will split cleanly over the
finger and clear whey will separate to fill the opened crack. Another
arbitrary but more or less satisfactory rule is that the time from
adding the rennet until cutting should be two and one-half times that
from the addition of rennet until the first sign of coagulation is
observed.
The condition of the curd itself is the best guide to show when it is
ready to cut. The condition of the curd is constantly changing, so that
in a large vat, if the cutting is not begun until the curd is in the
best condition, by the time the last of the curd is cut it will be too
hard or firm. It is better to begin while the curd is a trifle too soft
so that the cutting will be taking place while the curd is at the proper
stage. At best the last of the curd may become too hard. If too hard, it
will break ahead of the knife instead of cut. Breaking causes more fat
loss than cutting because there is more surface exposed and hence more
fat globules. The softer the curd when cut, the quicker and easier the
moisture can be expelled.
If the curd is cut when soft, care must be exercised not to stir it too
hard immediately after cutting. Soft curd breaks very easily. When the
curd is cut soft and then stirred vigorously, there is a larger loss of
fat than when the curd becomes hard before it is cut.
Two knives are used to cut the curd. (See Fig. 11.) These knives may
have either wire or blades for cutting. The space between the wires or
blades varies from 5/16 to ½ inch. Knives used should have blades or
wires close enough together to cut the pieces as small as desired,
without a second cutting. When the curd has to be cut a second time it
usually results in pieces of uneven sizes, because the pieces already
cut cannot be evenly split in two.
One set of knives has horizontal and the other perpendicular blades or
wires. The curd is cut the long way of the vat with the horizontal knife
and lengthwise and crosswise with the perpendicular knife so that the
result is small cubes or oblongs of curd. Some cheese-makers prefer to
use one knife first and some the other, but the result should be a curd
cut into pieces of uniform size. The smaller the particles of curd or
cubes are cut, the quicker the curd will firm up or cook. If not cut
uniformly, the changes taking place later in the curd particles will not
be uniform,--the small pieces will be hard and dry while the large ones
will be soft and mushy.
[Illustration: FIG. 32.--The proper way to put the knife into the curd.]
Care should be taken to let the knife cut its way into the curd (Fig.
32). If the knife is pushed into the curd, it will break it and cause a
large loss of fat. The same is true when taking the knives out of the
curd. The loss of fat due to cutting is very similar to the loss of
sawdust when sawing a board. It may be considered a necessary evil. The
loss due to cutting is about 0.3 of 1 per cent of fat in the whey and
the loss of casein about 0.1 of 1 per cent in the whey.
[Illustration: FIG. 33.--Acme curd rake.]
[Illustration: FIG. 34.--McPherson curd agitator.]
+197. Heating or "cooking" the curd.+--After the curd is cut, the pieces
(cubes) rapidly settle to the bottom of the vat and tend to mat
together. To prevent this, the curd must be kept stirred. When stirring
first begins, the curd is soft and very readily broken. Some
cheese-makers prefer to stir by hand for the first few minutes after
cutting, while the curd is soft. The importance of careful handling can
hardly be over-emphasized. No matter how well the curd has been cut, if
the stirring is performed in a careless manner in the early stages, it
will be broken into uneven sized pieces and a considerable loss of fat
will result. A wooden hay rake or a McPherson curd agitator (Figs. 33,
34) may be used to stir the curd. Mechanical curd agitators are used in
some cheese factories. There are several makes. (See Fig. 35.) These
agitators save much hand labor, although some stirring by hand must be
done in connection with them. The mechanical agitators do not stir the
curd in the corners of the vat; this must be done with the hand rake. It
is the usual practice to stir the curd immediately after cutting for
five to ten minutes before the mechanical agitators are used. This is
necessary to give the curd a slight chance to firm as the mechanical
agitators tend to break it up. After cutting, a thin film forms on each
piece of curd. This film holds the curd particles, especially the fat.
Breaking the films on the cubes causes loss of fat. If lumps form at
the early stage, by matting of the curd particles, violent stirring is
required to separate them. When such lumps are broken up, new cleavage
lines are formed with loss of fat, because the original films
surrounding the soft curd fuse so firmly that the curd cubes do not
separate but actually break. New surfaces are thus formed with
consequent fat loss. Rapid shrinkage with expulsion of whey takes place
during the first few minutes of gentle agitation. Before any heat is
applied to the vat, sufficient whey should have separated or formed to
float each piece of curd separately. This will require ten to fifteen
minutes from the time of cutting.
[Illustration: FIG. 35.--Two types of mechanical curd agitators.]
Thus far the first of three distinct factors which expel the moisture
from the curd has been considered: (1) the action of the rennet; (2) the
development of the lactic acid; and (3) the application of heat. These
forces must have time to act naturally. If heat is applied too soon
after the curd is cut or if the temperature is raised too rapidly, it
causes a thick film to form on the pieces of curd which interferes with
the escape of the whey. The outside of the curd becomes firm but the
inside remains very soft. A curd which is cooked on the outside only
feels firm when stirred by hand in the whey, but when a handful is
squeezed the soft centers are noticed. To firm such curd masses requires
violent stirring, which will break the thick tough film. This allows the
moisture to escape and also increases the fat loss. The rapidity of
heating should depend on the condition of the curd and the amount of
acid developed. The heat should keep pace with these. When ready to
raise the temperature, the least amount of steam possible should be
allowed to pass through the valve. This should raise the temperature
very gradually. If heat is applied too quickly at first, it will cause
the curd to lump. A safe rule is to raise the temperature one degree in
the first five minutes after the steam has been turned on. The heating
should progress slowly until the whole mass of curd in the vat has
reached a temperature of 90° to 92° F. The usual temperature to which
the curd is heated or cooked is 98° F. to 100° F. The lower the
temperature that can be used and properly firm the curd, the better will
be the body of the cheese. If the curd is heated too high, it will
become hard, which causes a dry hard "corky" cheese. After this
temperature has been reached, there is not such a tendency for the curd
particles to stick together nor are they so easily broken in stirring.
It should require, under normal conditions, not less than thirty to
forty-five minutes, from the time the steam is turned on, to raise
temperature of the curd from the setting temperature to that necessary
to "firm" the curd. If a shorter time is allowed to raise the
temperature, the curd will not have opportunity to contract naturally.
The temperature required to expel the moisture properly varies with the
percentage of fat in the milk. If rich in fat (4.5 to 5.5 per cent) milk
requires a temperature of 98° to 104° F. to firm the curd, while the
same result can be accomplished with milk testing 3.0 to 3.5 per cent
fat at a temperature of 94° to 96° F. A higher temperature is needed in
winter than in summer because the milk is usually richer in fat. In a
water-jacketed vat, allowance must always be made for the rise in
temperature due to the water surrounding it. The water may be removed if
there is danger of the temperature going too high. However, it is better
to gauge the heat so that the water may be left, as this helps to hold
the curd at an even temperature, especially in cold weather. In a
steam-heated vat there is not so much danger of the temperature running
up.
The stirring must be kept up after the steam has been turned off until
the curd has reached such a stage of contraction that it will not
readily pack or mat in the bottom of the vat. After the curd reaches
this stage it may be allowed to settle to the bottom and stirred only
occasionally until it is time to remove the whey. If the cheese room is
not warm and there is danger of the curd cooling, a cover should be
placed on the vat. The curd should not be allowed to settle for more
than fifteen minutes without stirring to keep each piece separate. This
is necessary to obtain uniform contraction of all curd masses.
+198. Removing the whey.+--To permit the normal changes in the curd to
take place naturally, two and one-half hours from the time the rennet
extract is added is ordinarily required before the whey is drawn. The
time of removing the whey is determined by two factors: one, the acid
development, and the other, the firmness of the curd. For the best
results, it is better to have the firmness of the curd a trifle ahead of
the acid development. When the proper acid development has been reached,
the whey must be removed, regardless of the firmness of the curd. If the
curd has not become firm enough by natural forces, when the acid
development has reached the proper stage to remove the whey, it must be
firmed by other means. If it is not firm enough, either by natural or
artificial means, when the whey is removed, a sour cheese is the result.
The acid development should not be allowed to go beyond 0.16 to 0.19 of
1 per cent acidity in the whey by the acid test or 1/16 to 1/8 of an
inch of acid on the hot-iron test, before the whey is removed.
+199. Hot-iron test.+[89]--This test is employed to determine the amount
of acid in the curd. A piece of iron, such as an iron pipe two feet
long, is heated in the fire to proper temperature. If the iron is too
hot it will burn the curd, and if not hot enough the curd will not stick
to the iron. When hot, it is taken from the fire and wiped clean with a
cloth. A handful of curd is taken from the vat and squeezed dry, either
in the hand or in a cloth. This curd is carefully pressed against the
hot iron and drawn away. If the iron is at the right temperature and the
curd has sufficient acid development, the curd will stick to the iron
and when pulled away will form fine threads. The length of these threads
determines the amount of acid in the curd. The acid is usually spoken of
in terms of the length of threads, as 1/8 inch of acid, ½ inch of acid
and the like. The curd must have a slight development of acid before it
will stick to the iron. This test takes advantage of the peculiar
properties[90] of curd which are produced by the action of the acid on
the casein.
+200. Firmness of the curd.+--The cheese-maker must be able to judge the
firmness of the curd by physical examination. The particles of curd
should have shrunken to about one-half their original size and should be
of uniform consistency throughout; they should not have any soft
centers. The curd should be firm and springy. When a double handful is
pressed and suddenly released, the curd particles should spring apart.
The curd should have a "shotty" feeling when in the whey. If the curd
has attained the proper firmness, and the acid has not reached the
correct stage to remove the whey, it may be left in the whey until
sufficient acid development has been attained. This is liable to cause
the curd to become too firm and to result in a hard dry cheese. If there
is no evidence of the presence of undesirable organisms, such as bad
odors, or gas holes in the curd, it is better to remove the whey and
develop the acid when the curd is in the "pack." The pack refers to the
first piling of the curd.
[Illustration: FIG. 36.--Whey siphon with strainer.]
The whey may be removed either by means of a faucet or gate in the vat
or by a siphon (Fig. 36). With either form of removal a whey-strainer
(Fig. 37) should be used to prevent loss of curd particles. It requires
considerable time for the whey to escape from a large vat. After the
curd has been heated to the proper temperature, it is well to remove a
portion of the whey. In doing this the surface of the whey should not be
drawn down quite to the top of the curd. When ready, the remaining whey
can be quickly removed.
[Illustration: FIG. 37.--Whey strainer with spout to fit into the gate
in the vat.]
If it is decided that the curd is not firm enough, when the whey is
drawn down to the surface of the curd and the acid has developed
sufficiently, the curd should be firmed up in the whey by stirring it
vigorously by hand before the remainder of the whey is removed. This is
commonly called "hand stirring." This difficulty results either from the
use of too much starter or from holding the milk until too much acid
development has taken place before adding the rennet. Hand stirring
accomplishes what natural forces would accomplish if given sufficient
time. If the curd does not firm naturally in the whey, there is a large
loss of fat and other solids, because the pieces of curd will have to be
broken up to allow the water to escape from the soft centers of these
masses. This loss can usually be reduced by firming the curd in the whey
or adding water rather than by stirring without either water or whey. If
the curd is not properly firmed, it carries extra whey into the cheese.
With the increase in whey, the amount of milk-sugar carried into the
cheese increases. This extra milk-sugar attacked by bacteria produces an
excess of lactic acid, which results in "sour" cheeses. This explains
why the curd is placed beyond the danger of over-development of acid by
removing so large a portion of the whey. If the curd is properly firmed
in the whey and the whey is removed before too much acid has developed,
it is impossible to make a sour cheese.
+201. Gathering the curd together.+--Before the last of the whey has
been removed, the curd should be pushed back from the faucet into the
upper two-thirds of the vat and spread in an even layer. This layer
should be six to eight inches thick. The curd can be pushed back with
the rake or a board which will fit crosswise in the vat, in which are
many holes. As soon as the whey has been removed so that there is not
enough to wash the curd into the lower part of the vat, the vat should
be tilted and a ditch eight to ten inches wide cut in the curd through
the center. The curd from the ditch should be removed to either side and
spread evenly. As soon as all the whey has been removed, the pieces of
curd scattered about in the vat should be gathered up and placed with
the remainder.
In some factories, instead of matting the curd in the vat, a curd sink
is used. This is a wooden receptacle about the size of the vat but not
so deep, with a slatted false bottom. It is fitted with castors so that
it can be easily moved about. A cloth is placed in the sink and the curd
and whey are dipped upon the cloth. The whey escapes very rapidly
through the cloth. The curd sink is an advantage in those cases in which
it is desirable to remove the whey from the curd quickly, such as high
acid curds which have to be hand stirred to firm the curd. The
disadvantage lies in the work required to keep the sink and the large
cloth clean.
+202. Matting or cheddaring+ is the distinctive feature of the Cheddar
process. It is the piling and matting of the curd. Whether the curd is
matted in the vat or in the curd sink, the process is practically the
same. The object of cheddaring is three-fold: (1) to control the
incorporation of moisture; (2) to control undesirable ferments, if
present in the curd; (3) to develop the texture desired in the cheeses.
[Illustration: FIG. 38.--A cheese knife.]
After the curd in the vat has become matted so that the particles stick
together, the masses on either side of the central channel are cut
crosswise into strips with a cheese knife (Fig. 38). The width of the
strip depends on the water-content of the curd at this stage. The more
water, the smaller should be the pieces of curd. This allows the whey to
drain away much more rapidly. As soon as the strips of curd are cut,
they should be turned over or stood on edge. A drain should be left
along the middle line of the vat and on each side. This permits the whey
to run away freely. If, on the other hand, the outlet is dammed up, the
curd may become "whey-soaked." This produces a soft mushy cheese which
sometimes is "acidy" or sour. After the curd is turned each time, all
crumbs of curd broken off should be brushed underneath the masses of
curd so that they will mat with it. They should never be placed on top
of the curd because they will not unite but will become dry and hard. If
the crumbs are not kept brushed up, they become dry and will cause an
open textured granular cheese and possibly lumps in the cheese. After
the pieces of curd have been turned several times, and the whey has
fairly completely drained away, they may be piled first two deep, then
three deep and so on, the depth of the piling being gauged by the
softness or amount of water in the curd and the temperature. The higher
the curd is piled, the more water it will retain (assimilate), so that
the amount of moisture in the curd is regulated by the size of the
pieces into which it is cut and the rapidity and depth to which it is
piled.
The curd should not be left too long from the time it is turned until it
is turned again. This period is usually about ten to fifteen minutes.
The moister the curd, the more often it should be turned. In turning,
care should be taken to keep the ends at the same temperature as the
remainder. This can be done by piling them inside, thereby keeping them
warm. There is a tendency for the ends of the pieces of curd to remain
granular and so cause an open-textured cheese.
During the cheddaring process, the temperature should be reduced
uniformly and gradually. If there is danger of the curd becoming too
cold, the vat should be covered and a pail of hot water may be placed
inside, if it is deemed necessary. The temperature of the curd should
not be allowed to go below 85° to 90° F. If kept too warm, the curd will
become soft and plastic, and if too cold, it will not mat together.
While the curd is being turned and piled, its physical properties are
changing. The acid develops. When the cheddaring process is completed,
the curd should be elastic, smooth and fibrous. The curd should have the
close meaty texture desired in the cheese. If this step in the process
is neglected, defects may appear later in the body, texture and flavor
of the cheese. Attempts to pile the curd too fast result in a soft,
mushy, open-textured product. Such cheese has mechanical holes, in which
moisture collects, and so is likely to cause rot while curing.
If gas is detected either before or during the cheddaring process, the
curd should be piled until the gas holes are no longer round but flat.
If the gas holes are not flattened or obliterated during this process,
the cheeses will be very liable to puff on the shelves in the
curing-room. The curd should be handled until the gas holes flatten out
evenly, although this may require considerable time. At best, gassy curd
will never produce the highest grade of cheese.
Cheddaring or piling the curd is not thoroughly understood by most
cheese-makers. Because the moisture contains the milk-sugar, there is
danger of having so much moisture present in the cheese that it will
become sour from the action of the lactic acid-forming bacteria on the
milk-sugar. A cheese may be sweet when made and later become sour
because it contains too much moisture or milk-sugar. This is known as
"shelf souring." For the proper cheddaring of a curd, it is necessary
that it be properly firmed in the whey. If the moisture is not evenly
incorporated, the cheese will have a mottled color. The pieces that have
the more moisture will be lighter colored. If the proper amount of
moisture is not incorporated, the cheese will be dry and hard, and if
too much, soft and pasty.
+203. Milling the curd.+--The large pieces formed by the cheddaring
process must be cut into small ones before the curd can be easily put
into the hoop. This is called "milling." Properly milled curd can be
salted evenly, cools more quickly and uniformly and can be distributed
evenly in the hoops.
The proper time to "mill" the curd is determined by its physical
condition. Some curds will cheddar much more rapidly than others, hence
no definite length of time can be given. Curd, when ready to mill,
should have a fibrous texture somewhat like the white meat of a chicken
breast. The pieces of curd should split very easily. When cut, the curd
should show a close, solid, smooth interior. The amount of lactic acid
developed may vary within rather wide limits. The hot iron may show
strings ½ to 1 inch long. The acidity (by titration of the freshly
separating whey) may be 0.45 to 0.65 of 1 per cent. If the curd has been
properly made, that is, firmed up in the whey with the proper acidity so
far, acid development during the cheddaring process will take care of
itself. The physical condition remains the principal means of
determining the time when the curd should be milled.
[Illustration: FIG. 39.--Gosselin curd-mill.]
[Illustration: FIG. 40.--Barnard curd-mill.]
[Illustration: FIG. 41.--Junker curd-mill.]
[Illustration: FIG. 42.--Harris curd-mill.]
There are many kinds and styles of curd-mills on the market. Gosselin,
Barnard, Pohl, Junker, Victor, Harris are well-known kinds (Figs.
39-42). Some are hand, others power mills. Some of these tear the curd
into pieces of unequal size, others cut it into uniform pieces. A mill
that will do the work with the least possible pressure on the curd and
which will cut it into small uniform-sized pieces is most desirable. The
ideal mill should release the least fat and leave the curd in the best
condition to receive the salt. It is impossible to run curd through any
mill without exposing some fat on the freshly cut surfaces, and if the
curd is put under pressure, more fat will be pressed out and lost.
Cutting in the mill, like cutting the curd after coagulation by rennet,
may be called a necessary evil. There is an unavoidable mechanical loss
which may be greater or less according to the mill used. If the curd has
been properly handled so that the water in it has become thoroughly
assimilated (properly incorporated), this loss will be reduced to the
minimum. If the curd contains free moisture and many of the particles
have soft interiors, a stream of white whey will run down the vat as the
curd masses are cut. Some samples of such white whey will test as high
as 15 per cent fat. This not only causes a loss in yield but in quality
of cheese, according to the amount of fat lost. White whey is an
indication of loss of fat. If the proper amount of moisture is present
and is so thoroughly incorporated in the curd that it can be separated
only by evaporation, the ideal condition has been reached. While
milling, the cut curd should be stirred as fast as milled to prevent
matting again and to allow odors to escape. This stirring is usually
performed with a curd fork (Fig. 43). At the same time the temperature
will be lowered. The milled curd should be spread evenly over the upper
three-quarters of the bottom of the vat. The flavor of the curd that has
been made from tainted milk can be very much improved by stirring at
this time so that air can enter.
[Illustration: FIG. 43.--A curd fork.]
A gassy curd, which has been held until the holes have become flattened,
should be stirred very frequently during this stage to allow the gas to
escape, thereby improving the flavor.
+204. Salting.+--Salt is added to Cheddar curd for several purposes: (1)
for its taste; (2) to aid in the removal of the whey and to harden and
shrink the curd; (3) to influence the fermentation by slowing down
acidification, checking the growth of unfavorable organisms and delaying
ripening. The salt should be pure. It should be coarse-grained, because
the large grains dissolve more slowly and permit its absorption to a
much larger extent than the fine-grained salt. Salt that dissolves
slowly is, therefore, to be sought for this purpose.
The following factors must be considered in determining the amount of
salt to be used: (1) the amount of curd from the milk; (2) the
percentage of water in the curd; (3) the acidity of the curd; (4) the
particular market form of cheese desired. The custom of determining the
quantity of salt by the weight of milk is an inaccurate practice. The
amount of salt should be based on the amount of curd. If the amount of
fat in the milk is known, a fairly accurate estimate of the amount of
curd can be made. It would be more accurate to weigh the curd before
salting, but this is not practicable or necessary to insure a good
quality of cheese. The amount of salt varies from 1½ to 2½ pounds
of salt to the curd from each 1000 pounds of milk.
The salt should not be added directly after milling because, at that
time, it would cause a large loss of fat. After milling there should be
time before salting for the freshly cut surfaces to dry or "heal over."
When first milled the curd has a dry harsh feeling; when ready to salt
it will feel soft and mellow and some moisture can usually be squeezed
out easily. Fifteen to twenty minutes from the time of milling are
required before the curd is ready for the salt. When ready, the curd
should be spread evenly over the bottom of the vat. The salt should be
carefully weighed, and then applied, evenly, over the surface of the
curd, in two or three applications. The curd should be thoroughly
stirred after each application of salt. While the salt is being
dissolved and absorbed, the curd should be stirred occasionally to
prevent lumps from forming.
[Illustration: FIG. 44.--Wilson press hoop. _A_, complete hoop; _B_,
bottom cover with wide flange; _C_, top cover with narrow flange; _D_,
closed body; _E_, bandager.]
[Illustration: FIG. 45.--Fraser press hoop. _A_, complete hoop; _B_,
bandager; _C_, follower; _D_, fibrous press ring.]
+205. Hooping the curd.+--When the salt has become dissolved and the
curd as soft and mellow as before the salt was added, it is ready to be
put into the hoop. Various sized hoops may be used, depending on the
desired size of the cheese. Two types are the Wilson and the Fraser
(Figs. 44, 45). With either type, a dampened press cloth should be cut
just to fit the bottom of the hoop. A starched circle may or may not be
used; if used, it should be placed on top of the press cloth. The
bandage now commonly employed is the seamless one which comes in the
form of a tube of various sizes for different sized hoops. The lengths
of bandage cut for each hoop or cheese depend on the height of the
cheese plus about one and one-half inches' lap on each end. The bandage,
after being cut the desired length, is placed on the part of the hoop
made to hold it, so that it is suspended about the side of the hoop and
laps about one and one-half inches on the bottom. The bandage should be
free from ravelings and placed squarely in the hoop.
The hoop is now ready to fill with curd. Enough hoops should be prepared
to hold all the day's curd as fast as it is ready. In order to have all
the cheeses as nearly as possible of the same size, it is advisable to
weigh the curd into the hoops. The curd may be measured into the hoops,
but this is not so accurate. The curd may be dipped with a flat-sided
curd pail or a curd scoop into the hoops (Fig. 46).
[Illustration: FIG. 46.--Curd scoop and pail.]
+206. Pressing the curd.+--The natural changes sought in the curd
require a period of at least five hours between the time of setting
(addition of the rennet) and the pressing of the curd. Less time than
this involves loss in yield and quality of the cheese. In other words,
the time requirement for these changes cannot be ignored. The object of
pressing is not primarily to remove whey but to produce the physical
conditions essential to ripening the cheese in a mass and put it in
convenient form for handling. The whey should have been removed during
the cooking and cheddaring. When ready for the press, the temperature of
the curd should be about 80° to 85° F.; it should be brought down to
this point during the milling, salting and hooping processes. If the
curd is put to press too warm or too cold, the following results may be
expected:
Too high temperature during pressing produces several faults, as:
(1) Favors the development of undesirable ferments.
(2) Causes excessive loss of fat.
(3) Gives the curd pieces a greasy surface so that they
will not readily pass into a compact cheese. If a cheese
is greasy, the bandages will not stick.
(4) Favors the formation of mechanical holes in the
cheese.
(5) Causes "seamy" color in the cheese by the collection
of fat between pieces of curd.
Too low temperature has its difficulties, such as:
(1) The pieces of curd will not fuse together.
(2) The rind does not form properly.
(3) It appears to cause mottled cheese.
[Illustration: FIG. 47.--Continuous pressure gang cheese-press.]
[Illustration: FIG. 48.--Filling the hoops and pressing the curd.]
The commonly used gang press may or may not have an arrangement to cause
continuous pressure to be applied to the cheese (Figs. 47, 48). When
fresh cheeses are first placed in the press, the pressure should be
applied very gradually. The curd, after being cut through the mill, will
have many exposed fat globules. A heavy pressure at first will force
out the whey set free by the extracting power of the salt. The whey will
carry away the exposed fat globules, and therefore reduce the yield. As
soon as white whey starts from the hoops, the increased application of
the pressure should be stopped until the whey regains the appearance of
clear brine. More pressure can then be gradually applied until full
pressure is reached. The cheeses should remain under heavy pressure for
one-half to one hour, when they should be removed from the press and
dressed.
+207. Dressing the cheese.+--When ready to dress the cheese, the press
is opened and the hoops turned down. The hoops are opened so that the
bandages can be lapped over the top of the cheeses about 1½ inches.
Before turning a bandage down, it should be carefully pulled up to
remove any wrinkles from the sides of the cheese, but not hard enough to
pull it free from the bottom. After it is pulled up, the bandage should
be lapped over the top about 1½ inches, and if not even should be
trimmed with a sharp knife. It should then be sopped down with warm
water. Plenty of warm water to wet the bandage and cloths helps to form
a good rind. If starched circles are used, one should be placed on the
top of the cheese and sopped down with warm water. If not, the press
cloth should be wrung out of warm water and put on smoothly, so there
will be no wrinkles. The hoop is then put together and placed back in
the press under heavy pressure for twelve to eighteen hours. The
pressure should be sufficient to cause the curd particles to unite so
that the surface of the cheese will be smooth. The next day the cheeses
are taken from the hoops and placed in the curing-room. If they do not
come out of the hoop easily, they may be loosened by cutting between the
sides of the cheese and the hoop with a knife. A special thin-bladed
knife for this purpose is called a speed knife (Fig. 49). Care should be
taken not to cut the bandage when trying to loosen the cheese. If
starched circles are used, the press cloths are removed from the cheese,
when they are put in the curing-room. If neither starched circles nor
press cloth are left on the cheese in the curing-room, the rind will
crack on account of drying out on the exposed surface. This allows mold
and insects to enter the cheese. The flavor, body and texture and color
of the cheese are all dependent on the skill of the cheese-maker and the
quality of the milk from which it is made. The finish is dependent
entirely on the skill and carefulness of the maker. An operator should
see that the cheese press is straight so that there will be no crocked
cheese and that the bandage and press cloths are properly put on,
because the finish or appearance of the cheese is an index of his
ability.
[Illustration: FIG. 49.--Speed knife.]
+208. Handling over-ripe and gassy milk.+--Because it is sometimes
necessary to make over-ripe[91] or gassy milk[92] into cheese, special
directions or precautions are necessary. The best way is to reject this
milk. When it is necessary to make it into cheese, the losses are much
more than with normal milk. It is a question of making as good a cheese
as possible, and the subject of losses is ignored.
(1) _Over-ripe milk._--The fact that the milk is over-ripe shows that
there is already too much acid present. Every effort must be made to get
the curd as firm as possible in the whey with the acid development as
low as possible or before the acid has had time to develop any more than
can be helped. Although the milk is over-ripe, it is a good plan to add
about ¼ of 1 per cent of starter just before the rennet. This starter
will not begin to work until the curd is being cheddared and it will
help the flavor, especially if any bad fermentation should be present.
The rennet is added at 80° F., as this lower temperature tends to check
the acid development. More rennet is used, commonly from 4 to 4½
ounces to 1000 pounds of milk. This gives a quicker coagulation. The
curd is cut soft, as this tends to expel the moisture more quickly. The
heat is turned on sooner after cutting. The time to turn it on and the
length of time to heat are determined by the amount of acid. A curd
should not be heated in less than fifteen minutes. If the curd has
enough acid and has not begun to firm up much, the whey should be drawn
down to the surface of the curd, water the temperature of the whey and
curd put into the vat, and the curd firmed up in this water. The water
washes the acid out of the curd and because of the lack of milk-sugar
checks the acid development.
If the milk is not so ripe and the curd nearly firm enough, the whey may
be drawn off and the curd firmed up by hard stirring in the vat or sink.
The curd should not be pushed back enough to be very deep or thick when
ready to cheddar.
The curd should be cut into very small pieces to cheddar. The smaller
the pieces, the faster the whey drains away. Sometimes it is necessary
to cut the curd into pieces six inches square. The pieces should not be
piled but should be turned often and stood on edge to let the whey drain
away and sometimes pressed with the hands to force the whey out. It is
often all one man can do to keep the curd turned.
[Illustration: FIG. 50.--At the left is a regular shaped, close, solid
textured cheese; at the right one puffed up with gas.]
The curd is not cheddared very long but is milled early so that the whey
can escape. If it is thought that the cheese will be sour, the curd
should be washed in cold water to remove the acid and milk-sugar. A
little more salt is sometimes used. A product made from over-ripe milk,
no matter how skillful the cheese-maker, will show traces of a sour
cheese.
(2) _Gassy milk._--If a cheese-maker knows that there is "gassy"
fermentation, he should add more starter and develop more acid when
ripening the milk to try to overcome this. There are different kinds of
gassy fermentation. Some produce acid and some do not. Some will not
show until the cheeses have been on the curing-room shelves several
days. Others will cause the curd to float in the whey. Usually the gas
shows as pin-holes while the curd is being cheddared.
[Illustration: FIG. 51.--This shows the same cheeses as in Fig. 50, cut
open to show the solid and gassy texture.]
The gas causes tiny round holes in the cheese, resulting in the cheese
swelling or puffing out of shape and sometimes breaking open (Figs. 50,
51). The only time to overcome the gas is during the cheddaring process.
The curd is piled and repiled until the holes flatten out. This shows
that the gas-producing organisms have weakened and will not cause any
more holes. Because the curd has to be piled so many times and so long,
the pieces become very thin. The curd is ready to mill when most of the
holes have flattened. After milling, the curd should be stirred and
aired for some time before salting to allow the bad odor to escape.
Because of the high acid development, it often happens that the cheese
will not be gassy but will be sour. At best a cheese made from milk
having gassy fermentation will have a bad flavor. The quality of the
cheese can be no better than that of the milk from which it is made,
plus the skill of the cheese-maker.
+209. Qualities of Cheddar cheese.+--The cheese should be neat, clean
and attractive. If unclean, and the bandage not put on the cheese
properly, it shows that the manufacturer is not particular to keep the
curing-room shelves tidy nor careful and painstaking in dressing. The
cheese should not be lopsided or bulged. When cut, it should have a
uniformly colored interior. The principal color defects are too high, or
too light color, mottled or seamy. The texture should be solid and
close. A common defect is mechanical holes or openings and another is
gas pockets. The body can be tested by rubbing the cheese between the
thumb and fingers. It should be smooth and waxy and free from lumps. It
should rub down like cold butter. The common defects are graininess and
lumpiness. Graininess may be caused by too much acid or too much
moisture in the cheese. Lumpiness is due to uneven curing. If too much
moisture is present, the body will be soft and mushy; if not enough
moisture, the body will be hard and dry.
The cheese should have a pleasant, clean, mild aroma and the
characteristic flavor which is usually somewhat similar to that of nuts
and so is spoken of as a nutty flavor.
CHAPTER XIII
_COMPOSITION AND YIELD OF CHEDDAR CHEESE_
So many factors affect the composition and yield of Cheddar cheese that
no positive or exact statement can be made unless other facts are
definitely known. The following factors affect both the composition and
yield:
1. The chemical composition of the milk.
2. Amount of moisture incorporated into the cheese.
3. The amount of solids lost in cheese-making.
4. The skill of the cheese-maker.
5. The bacterial-content of the milk.
+210. Composition of milk, whey and cheese.+--The
following Tables[93] VI, VII, VIII, which are the average
of forty-eight factories for the season of 1893, show the
minimum, maximum and average composition:
TABLE VI
AVERAGE COMPOSITION OF THE MILK
| Minimum | MAXIMUM | AVERAGE
--------------------|---------|---------|---------
Water | 86.28 | 88.30 | 87.28
Total solids | 11.70 | 13.72 | 12.72
Fat | 3.30 | 4.40 | 3.77
Casein | 2.20 | 2.85 | 2.48
Albumin | 0.52 | 0.81 | 0.69
Sugar and ash, etc. | 5.63 | 5.89 | 5.78
TABLE VII
AVERAGE COMPOSITION OF THE WHEY
| Minimum | MAXIMUM | AVERAGE
--------------------|---------|---------|---------
Water | 92.75 | 93.28 | 93.00
Total solids | 6.72 | 7.25 | 7.00
Fat | 0.24 | 0.51 | 0.38
Casein, albumin | 0.66 | 0.99 | 0.86
Sugar, ash, etc. | 5.63 | 5.86 | 5.76
TABLE VIII
AVERAGE COMPOSITION OF THE GREEN CHEESE
| Minimum | MAXIMUM | AVERAGE
--------------------|---------|---------|---------
Water | 33.16 | 43.89 | 37.33
Total solids | 66.84 | 56.11 | 62.67
Fat | 30.00 | 35.89 | 33.41
Casein | 20.80 | 25.48 | 23.39
Sugar, ash, etc. | 4.86 | 7.02 | 5.89
Table VI shows the minimum, maximum and average composition of the milk
and Table VIII the composition of the cheese made from that milk. The
average composition of the cheese in Table VIII shows that it contains
37.33 per cent of water. The tendency to-day seems to be for a softer
cheese so that the average would probably be higher. Table VIII also
shows the wide variation in the composition of the cheese. The moisture
and total solids both vary about 10 per cent. In order to judge the
variation in composition, one must know the composition of the milk and
the moisture-content of the cheese and then only a very inaccurate
estimate of the composition of the cheese can be formed.
+211. Relation of fat to casein in normal milk.+--In order to understand
the relation of the composition of the milk to yield of cheese, one must
be familiar with the relation of the fat to the casein in normal milk.
The following table[94] shows the relation of fat to casein in normal
milk:
TABLE IX
SUMMARY SHOWING THE RELATION OF FAT TO CASEIN
IN NORMAL MILK
====================================================================
| | | | | AVERAGE
| | | AVERAGE | AVERAGE | POUNDS OF
| PER CENT | NUMBER | PER CENT | PER CENT | CASEIN FOR
GROUP | OF FAT IN | OF | OF FAT IN | OF CASEIN | EACH POUND
| MILK | SAMPLES | EACH IN | EACH | OF FAT IN
| | | GROUP | GROUP | MILK
--------+-----------+----------+-----------+-----------+------------
I | 3.0-3.5 | 22 | 3.35 | 2.20 | 0.66
II | 3.5-4.0 | 112 | 3.72 | 2.46 | 0.66
III | 4.0-4.5 | 78 | 4.15 | 2.70 | 0.65
IV | 4.5-5.0 | 16 | 4.74 | 3.05 | 0.64
V | 5.0-5.25 | 7 | 5.13 | 3.12 | 0.61
====================================================================
Table IX shows that the pounds of casein for each pound of fat are not
constant but that the casein does not increase in proportion to the fat
above 4.0 per cent of fat in the milk.
+212. Influence of fat in milk on yield of cheese.+--The following table
shows the influence which fat in the milk has on the yield of
cheese:[94]
TABLE X
SUMMARY SHOWING RELATION OF FAT IN MILK TO YIELD
OF CHEESE
==============================================================
| AVERAGE PER | POUNDS OF GREEN CHEESE | POUNDS OF
GROUP | CENT OF FAT | MADE FROM 100 LB. OF | GREEN CHEESE
| IN MILK | MILK | MADE FOR 1 LB.
| | | OF FAT IN MILK
------+-------------+------------------------+----------------
I | 3.35 | 9.14 | 2.73
II | 3.72 | 10.04 | 2.73
III | 4.15 | 11.34 | 2.70
IV | 4.74 | 12.85 | 2.71
V | 5.13 | 13.62 | 2.66
==============================================================
Table X shows that as the fat in the milk increases, the pounds of
cheese made from 100 pounds of that milk increases; but the amount of
cheese made for each pound of fat in the milk does not increase. This is
due to the fact pointed out in Table IX, namely, that as the fat
increases in the milk the casein does not increase in the rich milk in
proportion to the fat. From Tables IX and X this conclusion may be
drawn: that as the percentage of fat increases in the milk the more
cheese can be made from 100 pounds of that milk, but after the increase
in fat gets above 4 per cent the amount of cheese that can be made for
each pound of fat in the milk is decreased because the casein does not
increase in proportion to the fat. No exact statement of yield can be
made without first stating the moisture-content of the cheese. The
losses also must be considered.
Van Slyke[95] in the following Table XI shows the effect of the
fat-content of normal milk on the yield of cheese.
The moisture-content of all the cheeses is reduced to a uniform basis of
37 per cent. (See cut showing yield of cheese, Fig. 52.)
[Illustration: FIG. 52.--The figures represent the relative yield of
cheese containing different percentages of fat, but all have a uniform
content of 37 per cent water.]
TABLE XI
TABLE SHOWING THE EFFECT OF THE FAT-CONTENT OF
NORMAL MILK ON THE YIELD OF CHEESE
----------------+-------------+--------------+-------------------
PER CENT OF FAT | PER CENT OF | AMOUNT OF | AMOUNT OF CHEESE
IN THE MILK | CASEIN IN | CHEESE MADE | MADE FOR EACH
| THE MILK | FROM 100 LB. | POUND OF FAT
| | OF MILK | IN THE MILK
----------------+-------------+--------------+-------------------
3.00 | 2.10 | 8.30 | 2.77
3.25 | 2.20 | 8.88 | 2.73
3.50 | 2.30 | 9.45 | 2.70
3.75 | 2.40 | 10.03 | 2.67
4.00 | 2.50 | 10.60 | 2.65
4.25 | 2.60 | 11.17 | 2.63
4.50 | 2.70 | 11.74 | 2.61
4.75 | 2.80 | 12.31 | 2.59
5.00 | 2.90 | 12.90 | 2.58
----------------+-------------+--------------+-------------------
+213. Fat loss in cheese-making.+--The amount of solids lost in the whey
also affects the yield. The following table gives the amount of fat lost
in whey with normal milk containing different percentages of fat:
TABLE XII
SUMMARY SHOWING AMOUNT OF FAT IN MILK LOST IN
CHEESE-MAKING
=================================================================
GROUP | POUNDS OF FAT IN | POUNDS OF FAT LOST | PER CENT OF FAT
| 100 LB OF MILK | IN WHEY FOR 100 | IN MILK LOST
| | LB. OF MILK | IN WHEY
------+------------------+--------------------+------------------
I | 3 to 3.5 | 0.32 | 9.55
II | 3.5 to 4 | 0.33 | 8.33
III | 4 to 4.5 | 0.32 | 7.70
IV | 4.5 to 5 | 0.28 | 5.90
V | 5 to 5.25 | 0.31 | 6.00
=================================================================
Table XII shows that the percentage of fat in the whey is approximately
the same for milk high or low in fat. But the milk low in fat loses a
higher percentage of the total milk-fat in each 100 pounds of whey.
+214. Effect of bacterial-content of milk on yield of cheese.+--The
bacterial-content[96] of the milk influences the yield by affecting both
the moisture-content and the losses. If the milk is sour or has bad
fermentation, the losses will be increased because the curd cannot be
carefully handled, and the moisture cannot be incorporated to the extent
that it can in clean milk, without injury to the quality. The
proper-cooling of the milk in one instance increased the yield 0.3 pound
of cheese for each 100 pounds of milk. The more moisture that can be
incorporated into the cheese up to the legal limit, the greater the
yield.
+215. Factors affecting the moisture-content of Cheddar.+--The amount of
moisture that can be incorporated in a curd depends on several
factors.[97] The following increase the moisture-content control of the
cheese:
1. Cutting the curd coarse.
2. High setting temperature.
3. Low acid in the curd at time of removing whey.
4. Not stirring the curd with the hand as the last of the whey is
removed.
5. Slow pressure.
6. High piling of the curd in the cheddaring process.
7. Small amount of salt.
8. Holding the curd at low temperature after the whey is removed.
9. Large amount of rennet.
10. Cutting the curd hard.
The following factors decrease the moisture-content of the cheese:
1. Fine cutting.
2. Low setting temperature.
3. High acid in the curd at time of removing the whey.
4. Stirring the curd with the hand as the last of the whey is removed.
5. Fast pressure.
6. Low piling of the curd in the cheddaring process.
7. Large amount of salt.
8. Holding the curd at high temperature after the
whey is removed.
9. Small amount of rennet.
10. Cutting the curd soft.
From this discussion, it is evident that the yield of cheese from 100
pounds of milk increases with higher percentages of fat and casein in
the milk, with reduced losses of solids during manufacture, with the
absence of undesirable fermentations, and with the incorporation of
large amounts of water.
+216. Variations of the Cheddar process.+--The Cheddar process, as
already described, is widely employed in cheese factories. Many
varieties are found, however, and varietal names are used for such
products. A whole series of these forms are either locally or widely
made in England and taught in the English dairy schools. Some of these
varieties resemble the factory Cheddar product fairly closely; others
are clearly different products. A typical series of the variations as
developed in America will be considered.
In the commercial trade Cheddar cheese is usually designated by some
name which indicates its size. The size of the cheese is determined by
that of the hoops. The hoops vary both in diameter and height. The table
on the following page shows the usual sizes of the hoops and the weight
and name applied to the cheese.
+217. Cheddar-type cheese from pasteurized milk.+--Sammis and Bruhn[98]
have described a variation of the Cheddar process to overcome the
difficulties of making cheese from pasteurized milk. Such milk curdles in
very unsatisfactory manner unless some chemical is added to compensate
for the salts lost and to offset the other changes resulting from heat.
For this purpose, they found the use of hydrochloric acid satisfactory.
TABLE XIII
SIZE OF CHEESE HOOPS, WEIGHT, AND TERM APPLIED TO
CHEESE
========================================================================
DIAMETER OF | HEIGHT OF | WEIGHT OF | TERM APPLIED TO
HOOP | CHEESE | CHEESE | CHEESE
| | POUNDS |
---------------+-------------------+------------+-----------------------
6-7 in. | 7-8 in. | 9-11 | Young America
Tapers 5-7 in. | 10-14 in. | 10-16 | Long Horn
12-14 in. | 3½-4½ in. | 18-24 | Daisy or Picnic
14-15½ in. | 4-6 in. | 30-40 | Twin (two in same box)
14-16 in. | 4-7 in. | 35-40 | Flat
13½-15 in. | 10-12 in. | 40-50 | Cheddar
14-16 in. | 12-15 in. | 75-90 | Export
========================================================================
"The acidulation of milk with hydrochloric acid after pasteurization is
accomplished without difficulty or danger of curdling by running a small
stream of the acid, of normal concentration, into the cooled milk as it
flows from the continuous pasteurizer into the cheese vat. One pound of
normal-strength acid is sufficient to raise 100 pounds of milk from 0.16
percent to 0.25 percent acidity (calculated as per cent of lactic acid).
The amount of acid needed each day to bring the milk up to 0.25 per cent
acidity is read from a table or calculated from the weight of the milk
and its acidity, determined by the use of Manns's acid test (titration
with tenth-normal sodium hydrate and phenolphthalein). The preparation
of standard-strength acid in carboy lots for this work and the
acidulation of milk present no great difficulty to any one who is able
to handle Manns's acid test correctly.
"After the milk is pasteurized and acidulated three-fourths per cent of
first-class starter is added and the vat is heated to 85°. It is set
with rennet, using 2 ounces of rennet per thousand pounds of milk, so
that the milk begins to curdle in 7 minutes and is cut with three-eighth
inch knives in 25 minutes. All portions of the work after adding rennet
are carried out in an unvarying routine manner, according to a
fixed-time schedule every day. As soon as the rennet has been added the
cheese maker is able to calculate the exact time of day when each of the
succeeding operations should be performed, and the work of making the
cheese is thus simplified and systematized. It is possible that the
routine process here described may be varied somewhat with advantage at
different factories."
This cheese usually lacks characteristic Cheddar flavor or contains it
in very mild form. It therefore satisfies only those who seek very mild
flavored products. Efforts are now being made to find a flavor producing
substance or organism which will bring the flavor of this product more
nearly to that of typical Cheddar.
+218. Club cheese+ is known by a variety of trade names. It is made from
Cheddar cheese, so that it is especially liked by persons who care for
strong Cheddar flavor. It has a soft texture so that it spreads easily,
and is therefore much used for sandwiches. Well-ripened or old Cheddar
cheese is ground in a food chopper. The older the Cheddar, the stronger
will be the flavor of the club cheese. Cheese of good flavor should be
used. In order to do away with all lumps in the texture, it is sometimes
necessary to run the mixed cheese through the food chopper a second
time. While all lumps must be worked out, care should be taken not to
work the cheese so much that it will become salvy and sticky.
Usually a little pepper is added, to give the cheese a biting taste.
Some manufacturers add a great variety of substances, but these are not
necessary and destroy the flavor of the cheese.
Club cheese may be wrapped in tin-foil or put up in air-tight glass
jars. The latter practice, while more expensive, has the advantage of
making the cheese keep longer; but for local trade tin-foil is just as
satisfactory as glass. In filling the glass, care must be taken not to
leave any air spaces between the cheese and the glass, as this is likely
to permit the cheese to mold. A glass jar can be filled and air spaces
prevented by first smearing a very thin layer of cheese over the glass.
+219. The stirred-curd or granular process.+--The original practice as
brought from England and followed in the farm dairies before the
development of the factory system is now known variously as the
"stirred-curd" or "granular curd" process. With the introduction of the
cheese factory, as known to-day, this system was replaced by the Cheddar
cheese. The old farm process is still used on some farms and in a few
factories. As the name indicates, the curd for such cheeses is kept
stirred so that it remains in granular condition instead of being
allowed to mat as in the Cheddar process.
The early steps of the two processes are identical. They diverge at the
point at which in the factory Cheddar process the whey is drawn and the
curd is allowed to mat. In some factories the curd and part of the whey
are dipped into a curd sink. This allows the whey to escape more easily
and quickly. In the stirred-curd process, the pieces of curd are kept
separated by stirring and not allowed to mat. The whey is drawn off and
the stirring continued by hand. After stirring fifteen to twenty
minutes, the curd becomes so dry as not to mat easily. As soon as the
curd has reached this stage, the salt is evenly and thoroughly mixed
with it. More salt is added than in the Cheddar process because the curd
is more moist than Cheddar curd at the time of salting. The whey freely
separating carries away much of the salt. The quantity of salt to use
depends on the amount of whey draining from the curd. After salting, the
curd is allowed to cool, with occasional stirring to prevent the
formation of lumps. The advantage of the stirred-curd practice lies in
the shorter time required for making cheese and in the greater yield due
to increased water-content. It has several disadvantages, among them
being: (1) lack of control of undesirable fermentation; if gas organisms
are present, the cheeses more frequently huff than with the Cheddar
system; (2) there is more fat lost while stirring the curd, hence
quality and yield suffer; (3) the water is not so thoroughly
incorporated, which more frequently results in mottled cheeses; (4) the
body is commonly soft and "weak," shows mechanical holes, and cures too
rapidly. These faults are closely correlated with the presence of higher
percentages of water than in cheeses made by the Cheddar process. In
other words, the stirred-curd process usually produces a cheese with
higher water-content, hence more subject to the development of
unfavorable fermentation than the Cheddar cheeses.
+220. California Jack cheese+[99] is very similar to the stirred-curd or
granular process. This cheese was originally made in Monterey County on
the coast of California, about twenty-five years ago, in small
quantities, but after it was found to sell well other counties started
to manufacture it. As Monterey was the first county to make this
product, it was named "Monterey" cheese. In order to distinguish the
cheese made in other counties from this, it was suggested that it be
given a name and, consequently, it was called "Jack" cheese. This has
been accepted as its true name. The cheese is made mostly by Portuguese
and Italian-Swiss, although some of the best of the variety is now
manufactured near Modesto, California.
This cheese is adapted for manufacture on small dairy farms, where there
is inexpensive and scanty equipment. The smaller sizes of cheese are
made and ripened quickly. It has become widely used in California.
The cheese is made every morning, from evening's and morning's milk. The
former is put into the cheese vat at night, and morning's milk is added
as milking is going on. When the milk is all in the vat, it is
immediately warmed to 86° to 88° F. and rennet extract is added (when
milk has 0.2 to 0.21 of 1 per cent acidity) at the rate of 6 to 8 ounces
to 1000 pounds of milk. No coloring matter is used. It is ready for the
curd-knife in thirty to thirty-five minutes, its readiness being
determined the same as in making Cheddar cheese. The curd is first cut
lengthwise of the vat with the horizontal curd-knife and allowed to
stand until the whey rises over and partly covers the curd, when it is
cut again with the vertical curd-knife crosswise of the vat. It is then
hand-stirred, gently at first, and the stirring is finished with the
rake.
Either a steam-heating or self-heating vat is used (the steam-heating
vat is preferred) and temperature increased about one degree in five
minutes. The curd is heated to 98° F. in winter, and to 105° F. to 110°
F. in summer. After temperature is up, it is stirred occasionally with a
rake until the whey is drawn at 0.14 to 0.15 of 1 per cent acidity.
The curd is hand-stirred as soon as the whey is nearly drained off, and
raked to each side of the vat to drain more thoroughly, when it is
quickly stirred again to keep it from lumping or matting. Salt is now
added at the rate of 1½ pounds to 100 pounds of curd, and stirred in
thoroughly several times. During the salting process, cold water is
allowed to run under the vat, the hot water having been run off
previously.
Curd is put into cloths at a temperature of 80° to 85° F. No cheese
hoops are used. Two sets of press cloths are necessary; one set is ready
to use while the other is still on the cheese in the press. These press
cloths are about one yard square. The press cloths are all laid out
evenly one on top of the other, as many as there are cheeses. They are
then taken together and spread out over the top of a large, open tin
milk-pail, and pushed down in the center to the bottom of the pail, with
the edges hanging over the top. A common one-gallon lard pail is used to
measure the curd into the press cloths. A lard pail full will make a
cheese weighing six and one-half pounds, which is the popular size.
After a pailful has been put into the press cloth, the four corners are
caught up with the left hand, while with the right hand the curd is
formed round and the press cloth straightened and the other corners in
turn taken up. The press cloth is now taken up tight over the curd with
the left hand, while the cheese is given a rolling motion on the table
with the right hand, pressing at the same time to expel some of the
whey. This twists the press cloth tight over the curd, where it is tied
with a stout string. After fixing them all (as many as there are
cheeses) in this way, they are ready for the press.
The cheeses are pressed between two wooden planks, 12 inches wide, 1½
inches thick, by whatever length is required for the number of cheeses
to be pressed. One plank is nailed on supports at a convenient height
from the floor on a little slant for the whey to drain off better. The
cheeses in the press cloths are placed at the proper distance apart so
they do not touch. Then the other plank is put squarely over the top of
the cheese and levers about four feet long at an interval of five feet
are placed over this plank, from a cleat in the wall, on the other end
of which is placed a heavy weight of about 100 pounds, which acts as an
automatic pressure. The cheeses are left in the press until the next
morning, when they are taken out and put on the shelves in the
curing-room. The cheeses have no bandage or covering, and do not seem to
crock, and they form a very good rind.
The cheese is a sweet variety, weighs six and one-half pounds cured and
cures in about three weeks ready to ship, and sells at 16 to 25 cents a
pound wholesale. Most of the work seems to lie in forming and rolling
the curd in press cloths before pressing. Trouble is experienced by the
makers, especially in warm climates in summer, in not having the milk at
a uniform acidity when rennet is added. Great improvements could be made
in this cheese by using an acidimeter, paraffining and curing the cheese
in an even temperature, not much over 60° F.
Old and hard Jack cheese is also employed for grating and cooking, while
the fresh is used for the table.
+221. The washed-curd process+ has been developed in recent years
largely in the state of New York. In this method, a regular Cheddar curd
is made up to the time of milling. This curd is washed or soaked in cold
water during or directly after milling. The theoretical object of this
washing is to carry away bad flavors and to reduce over-development of
acidity by washing away all traces of whey. However, cheese-makers soon
found that it increased the yield and this led some to carry it to
extremes.
After the curd has been milled, it is covered with cold water. The
temperature of this water ranges from 50° F. to 70° F. The curd is
stirred in this water for various lengths of time according to the
judgment of the cheese-maker. This time varies from five minutes to one
hour. Sometimes the vat is partly filled with water and the curd milled
directly into the water. This process has certain advantages and
disadvantages.
The advantages are: if too much acid has developed in the curd, this
washing will reduce it so that the cheese will not be sour. Sometimes
when bad flavors are present in the curd, washing will tend to overcome
or remove them. Its disadvantages are: the larger yield due to excessive
soaking tempts the makers to soak curd beyond the time needed to relieve
the initially sour condition. Curd soaked in this way produces cheeses
containing percentages of water so high as to lower their quality. This
increases the yield sometimes as much as 3 to 5 per cent. Such a cheese
is very soft in texture and does not cure like a Cheddar cheese which
has not been washed. Part of the lactic acid, milk-sugar[100] and the
inorganic salts are removed by this washing. A washed-curd cheese will
sometimes rot, due to the activity of the putrefactive bacteria, and to
the lack of the restraining effect of the lactic acid-forming bacteria.
Some washed-curd cheeses are so soft that they will not retain their
normal shape.
A washed-curd cheese is never sour because the milk-sugar and lactic
acid have been removed by washing.
+222. English dairy cheese.+--In some localities cheeses are still made
on the farms. These are mostly produced after the stirred-curd process,
hence are soft-bodied and open-textured. They usually weigh ten to
twelve pounds and are three to four inches thick and twelve inches in
diameter.
+223. Pineapple cheese.+--This variety derives its name from the fact
that the cheeses are made in about the size and shape of a pineapple.
The curd is made after the Cheddar process from either whole milk or
partly skimmed milk. It is pressed in molds shaped like a pineapple. The
cheeses are then hung in nets to give the checked appearance on the
surface. They are rubbed with linseed oil to prevent the surface
cracking, and finally are shellacked.
+224. Leyden.+--Among specialties, a cheese called Leyden originating in
Holland is made in Michigan and New York. This is a part skim cheese
heavily spiced with caraway seed. The ripe cheese is colored red as it
goes to market.
+225. Cheddar cheese with pimientos.+--Recently some Cheddar cheeses
have been made with pimientos added. This gives a mixture of
characteristic Cheddar and pimiento flavors, which seems to be desired
by some persons. An ordinary Cheddar curd is made and the pimientos
added just before salting. The pimientos are ground rather coarsely and
then added to the curd together with the liquid which was with the
pimientos in the can. The pimiento should be thoroughly and evenly
mixed with the curd to insure a uniform distribution and mottled color
in the cheese. The salt is then applied. The remainder of the process is
the same as for ordinary Cheddar cheese.
+226. Sage cheese+ is a product flavored from the leaves of the ordinary
garden sage. It is made by two methods: one, in which the sage leaves
are used, and the other, in which a part of the curd is colored to
imitate that given by the sage leaves, and sage oil or tea is used to
give the flavor.
In the leaf method, a regular Cheddar cheese curd is made up to the time
of salting. Just before the salt is added, sage leaves are mixed with
the curd. The leaves should be dried and freed from stems and other
coarse particles and the leaves themselves broken up rather finely. The
leaves are then added at the rate of 3 ounces for every 1000 pounds of
milk. Care must be exercised to see that the leaves are evenly mixed
through the curd or an evenly mottled cheese will not result. The salt
is then added. This sequence seems to increase the absorption of the
flavor by the curd.
If these cheeses are consumed as soon as well cured, no fault can be
found. On the other hand, if they are held for any length of time,
yellow areas form about each piece of sage leaf; the leaves decay
rapidly and spoil the cheese. This method gives a very true flavored
sage cheese, the only objection being that it cannot be held in storage
for any length of time without a marked deterioration.
In the other method of making sage cheese, either a vat with a movable
partition or a large and a small vat must be used. In many cases the
receiving can is used as the small vat. After the milk is properly
ripened and ready to set, one-sixth to one-seventh of the milk is put
into the small vat. To this small vat, green coloring matter is added.
Juice from the leaves of corn, clover, or spinach was formerly used as
coloring. Consequently the manufacture of sage cheese by this method was
limited to the seasons of the year when these leaves could be obtained.
Now, however, the dairy supply houses have a harmless green color paste
which is much cheaper and can be secured at any season of the year. The
amount of color paste to use will vary from 30 to 35 c.c. for every 1000
pounds of total milk. This should be added to the small vat of milk. It
gives a green milk and later a green curd.
Both vats are worked along together, until the time for removing the
whey. Then the partition in the vat is removed or the small vat is mixed
with the large one. The green curd should then be evenly mixed with the
white one or an even green mottled cheese will not result. The curds
should not be mixed until they are well firmed or the white curd will
take on a greenish cast and spoil the appearance of the cheese.
After the whey is removed, the curd is allowed to mat as in ordinary
Cheddar but care must be exercised to pile the curd so that it cannot
spread or "draw" out. If it does draw out, the small green spots will be
stretched out and large blotches or patches of green will be the result.
The cheese-maker must watch the curd closely or he may not secure the
much desired small green mottles. When the curd is well matted, it is
milled as in Cheddar. Just before the salt is added, the sage extract is
applied to the curd.
The sage extract can be obtained from dairy supply houses, or a sage
tea can be made by steeping the sage leaves. In many cases the
commercial extract gives the cheese a strong disagreeable flavor, but
not a true sage flavor. The sage tea gives a flavor more like that of
the leaves themselves. Too much of the extract or the leaves will give a
very rank flavor. The sage extract can best be put on the curd by means
of a sprayer or atomizer with which it can be evenly sprayed over the
entire surface. The extract should be applied two or three times and the
curd well stirred after each application. The amount of the extract to
use depends altogether on its strength; an ounce of the extract or three
ounces of sage tea to 1000 pounds of milk is about the correct amount.
After the extract has been added, the salt is used at the same rate as
with a normal Cheddar curd and the sage curd is carried along the same
as a Cheddar.
This extract method gives a sage cheese mottled with small green spots
which somewhat resemble the green of sage leaves. A cheese made in this
way can be held for a long time, as nothing has been added which can
decay. The only objection to this method is that the sage extract may
not give a true sage flavor. Therefore, the maker must try to obtain the
best extract possible or make his own from the sage leaves.
+227. Skimmed-milk Cheddar cheese.+[101]--The process of making
skimmed-milk cheese after the Cheddar process is varied with the amount
of fat left in the milk. Before attempting to make skimmed-milk Cheddar,
one should become familiar with the process for whole-milk Cheddar.
Skimmed-milk cheeses are usually highly colored.
When part skimmed-milk cheese is manufactured, there is often
difficulty in getting the milk in the vat to test the desired percentage
of fat. Some cheese-makers skim all the milk and then put in the desired
amount of cream. This practice seems wasteful, not only because of the
cost of separation, but because the fat will not mix easily with the
milk but will tend to float on the surface. If the fat floats, there
will be a large loss. After a very few trials an operator can tell about
how much of the whole milk must be skimmed in order to have the mixed
skimmed-milk and whole milk test the desired percentage of fat. The
necessary percentage of fat in the mixed milk to produce cheese of a
certain grade can be determined by testing the cheese by the Babcock
test. (See Chapter XIX.)
+228. Full skimmed-milk Cheddar cheese.+--In the summer there is not
much demand for full skimmed-milk cheese, but it is made in large
quantity in winter. The method of manufacture is as follows:
Skimmed-milk as it comes from the separator is at a temperature of about
88° to 90° F.; it is ripened and set at this temperature. It is ripened
rather highly on the acid test, from 0.18 to 0.20 of 1 per cent, and to
correspond on the rennet test which will not be many spaces. In about
twenty-five to thirty minutes it is coagulated ready for cutting. The
curd of skimmed-milk cheese is cut a little softer than is that of
whole-milk cheese. Milk is usually set at 88° to 90° F. The curd is not
ordinarily cooked above this temperature. If the milk was 84° to 86° F.
when set, then the curd should be raised to 88° to 90° F. The curd firms
in the whey very rapidly. When firm enough, it should have a slight
development of acid. On the acid test it should show 0.17 to 0.19 per
cent, and on the hot iron 1/8 to ¼ of an inch. The milk should be ripe
enough or starter enough should have been used, so that the acid will
continue to develop in the "pack" very rapidly. During the cheddaring
process the curd is piled more rapidly and in higher piles than is
customary with whole-milk cheese. This is necessary to incorporate or
assimilate a large percentage of water or whey in the cheese. Therefore
the process of skimmed-milk Cheddar cheese is much shorter. More acid is
developed with the skimmed-milk than with the whole-milk cheese because
it seems necessary to develop proper texture. If the acid is not
developed sufficiently, the cheese will be very rubbery and cure very
slowly, in which case bad fermentation and flavor may and often do
develop. The curd is turned, piled or cheddared in the vat until it
begins to become meaty and fibrous. If there is danger of too much acid,
the curd may be rinsed off with water. It is then milled and salted at
the rate of 1 or 1¼ pounds of salt to the curd from each 1000 pounds
of milk. The remainder of the process is the same as that for making
whole-milk cheese.
+229. Half skimmed-milk Cheddar cheese.+--No definite directions can be
given for the manufacture of part skimmed-milk cheese, because the
process varies with the amount of fat left in the milk. As the fat is
decreased, the process becomes more like that for making full
skimmed-milk cheese; as the fat is increased, the process becomes more
like that for whole-milk cheese. However, the process of making half
skimmed-milk cheese is about midway between the two. The milk is ripened
more than it would be for whole-milk cheese, usually until it tests from
0.15 to 0.17 of 1 per cent acid. The curd is coagulated and cut the same
as for the other skimmed-milk cheeses. It is cooked to a temperature
just sufficient to firm the curd, usually from 94° to 96° F. The lower
the temperature at which the curd can be cooked and yet become firm,
the better is the texture of the cheese. When the curd has firmed
enough, or when sufficient acid development, from 0.15 to 0.17 of 1 per
cent, has taken place, the whey is removed. The curd is then turned,
piled or cheddared. A skimmed-milk curd may be piled much more rapidly
than a whole-milk curd without danger of injuring it. When the curd
becomes meaty or fibrous, it is milled. It should be salted at the rate
of 1¼ to 2 pounds of salt to the curd from each 1000 pounds of milk.
The remainder of the process is the same as that for making whole-milk
cheese.
The cheese-maker should observe the following points when making
skimmed-milk cheese: (1) Have clean-flavored sweet milk; (2) use
clean-flavored commercial starter; (3) ripen the milk sufficiently, but
not too much; (4) firm the curd at as low a temperature as possible; (5)
have the curd properly firmed when the whey is drawn; (6) cheddar the
curd faster than the curd from whole milk; (7) make the cheeses all the
same size; (8) keep the cheese neat and clean in the curing-room.
+230. Yield and qualities of skimmed-milk Cheddar cheese.+--The results
of skimming different percentages of whole milk containing varying
percentages of fat are given in the following table. As the percentage
of fat in the milk decreases, the yield of cheese also decreases,
according to the table. As the percentage of fat decreases in the milk,
the percentage of moisture in the cheese increases, showing that
moisture is substituted for fat. The yield of cheese from 100 pounds of
milk is also given in this table. This yield varies with the amount of
moisture incorporated into the cheese, the amount of solids not fat in
the milk, and the solids lost in the whey.
TABLE XIV
TABLE SHOWING THE COMPOSITION AND YIELD OF SKIMMED-MILK
CHEDDAR CHEESE
============================================================================
| |PERCENTAGE|NUMBER | COMPOSITION OF THE CHEESE
PERCENTAGE|PERCENTAGE|OF FAT IN |OF POUNDS +----------+----------+----------
OF FAT |OF THE |THE MILK |OF CHEESE |PERCENTAGE| |
IN THE |MILK |IN THE |FROM 100 |OF TOTAL |PERCENTAGE|PERCENTAGE
MILK |SKIMMED |VAT AFTER |POUNDS |OF TOTAL |OF FAT |OF WATER
| |SKIMMING |OF MILK |SOLIDS | |
----------+----------+----------+----------+----------+----------+----------
4.7 | 50 | 2.4 | 9.92 | 54.75 | 22.00 | 45.25
4.7 | 60 | 2.0 | 9.74 | 52.46 | 17.50 | 47.54
4.7 | 70 | 1.5 | 9.26 | 49.87 | 13.50 | 50.13
4.7 | 80 | 1.0 | 8.42 | 48.26 | 10.00 | 51.74
4.0 | 50 | 2.0 | 9.70 | 53.29 | 21.00 | 46.71
4.0 | 60 | 1.6 | 9.50 | 50.89 | 17.00 | 49.11
4.0 | 70 | 1.2 | 9.30 | 48.06 | 13.50 | 51.94
4.0 | 80 | 0.9 | 9.20 | 45.24 | 10.50 | 54.76
3.5 | 50 | 1.8 | 8.54 | 54.20 | 19.50 | 45.80
3.5 | 60 | 1.5 | 8.10 | 51.10 | 16.50 | 48.90
3.5 | 70 | 1.1 | 7.44 | 52.62 | 13.00 | 47.38
3.5 | 80 | O.9 | 7.00 | 49.64 | 9.54 | 50.36
3.4 | 50 | 1.9 | 8.24[102]| 54.50 | 20.00 | 45.50
3.4 | 60 | 1.5 | 7.82 | 52.05 | 16.50 | 47.95
3.4 | 70 | {1.4 | {7.80 | {49.04 | {14.00 | {50.96
| | {1.2 | {7.28 | {50.76 | {14.00 | {49.24
3.4 | 80 | 0.9 | 7.24 | 47.41 | 10.50 | 52.59
============================================================================
In some creameries and cheese factories, the milk is skimmed and the
cream made into butter and the skimmed-milk into cheese by the Cheddar
process. In making cheese without the milk-fat, it is difficult to
standardize a method that will produce the flavor and body of the
whole-milk Cheddar cheese. A skimmed-milk cheese lacks the softness and
mellowness of texture of the whole-milk product. It is very likely to be
tough, dry or leathery. It is attempted to remedy this defect by
incorporating more moisture into the skimmed-milk cheese. The added
moisture tends to replace the fat in giving a soft mellow body. It
requires skill on the part of the cheese-maker to incorporate moisture
to take the place of the fat in giving the cheese mellowness and
smoothness of body.
The grades of skimmed-milk cheese vary between rather wide limits--from
those made entirely of skimmed-milk to those made of milk from which
only a small amount of fat has been removed and which are almost like
whole-milk cheese. Because of the gradations of skimmed-milk cheese, it
is difficult to make anything but general statements and to base
comparisons with whole-milk cheese.
CHAPTER XIV
_CHEDDAR CHEESE RIPENING_
Freshly made Cheddar cheese is hard, tough and elastic and lacks
characteristic cheese flavor. In this condition it is called "green,"
unripe or not cured. Before the cheese is ready to be eaten, it passes
through a complex series of changes which are collectively known as
ripening. In the ripening process the texture becomes soft and mellow
and the characteristic cheese flavors develop. Cheese ripening must be
considered from two view-points, first, the changes taking place inside
the cheese and secondly the outside conditions necessary for ripening.
Some of the chemical changes during ripening are known, while others are
not understood. The different agents causing ripening, and the
constituents of the milk, will be discussed.
+231. Fat.+--Numerous investigations have been made to ascertain what
chemical changes the fat undergoes in the ripening process. Suzuki,[103]
in studying the fat, found no enzyme capable of producing lactic acid or
volatile fatty acids. However, these acids were found in increasing
amounts during the ripening process and after the lactose had
disappeared. Acetic and propionic acids reached a maximum at three
months and then decreased, while butyric and caproic acids continually
increased during the experimental period covered. Formic acid was
detected in the whole-milk cheese only at the five and one-half month
stage. In the judgment of the experimenter the principal source of
acetic and propionic acids was probably lactates. Traces of these acids
may have had their origin in protein decomposition or further
fermentation of glycerine. The principal sources indicated for butyric
and caproic acids were fats and proteins.
The distillate from the experimental cheese was designated "flavor
solution" and contained alcohols and esters, giving a close resemblance
to the cheese aroma. The "flavor solution" from the mild whole-milk
cheese contained esters made up largely of ethyl alcohol and acetic
acid, while from the more pungent skimmed-milk cheese the esters were
largely compounds of ethyl alcohol and caproic and butyric acids. The
alcohol may have come from the lactose fermentation. It appears to be an
important factor in flavor production. The agencies operative in the
production of volatile acids and syntheses of esters are as yet
undefined.
+232. Milk-sugar.+--The milk-sugar (lactose) is changed into lactic acid
by the lactic acid-forming organisms, within the first few days after
the cheese is made. This acid is combined with the other constituents as
fast as it is formed. After a few days, the milk-sugar will have
entirely disappeared from the cheese.[104] The relation between the
milk-sugar and lactic acid is very close. It is necessary that
milk-sugar be present in order later to have the lactic acid develop.
+233. The salts.+--Just what changes the salts[105] undergo or how they
combine with the other compounds is not definitely known. It is supposed
that the calcium salts first combine with the phosphates and later, as
the lactic acid is formed, they combine with the lactic acid, forming a
calcium lactate.
+234. Gases.+--In the process of cheese ripening, gases are formed, the
commonest being carbon dioxide.[106] Exactly how this gas is formed is
not known. It may be due to the formation of lactic acid from the
milk-sugar or to the living organisms in the cheese.
+235. Casein or proteins.+--Complex ripening changes in the cheese take
place in the casein compounds or proteins. Because of the complex
chemical nature of the proteins and the various agents acting on them,
it is difficult to follow these changes. This has led to different
opinions regarding the ripening process. The various compounds thought
to be formed from the casein or proteins are as follows:[107]
_Paracasein_ (formed by the action of the rennet on the casein).
Insoluble in brine and warm 5 per cent salt brine.
_Protein._ Soluble in warm 5 per cent salt brine.
_Protein._ Insoluble in warm salt brine or water.
_Paranuclein._ A protein soluble in water and precipitable by dilute
hydrochloric acid.
_Caseoses and proteoses._ Protein derivations soluble in water and not
coagulated by heat.
_Peptones._ Protein derivations simpler than the proteoses, soluble in
water and not coagulated by heat.
_Amido acids._ Protein derivations soluble in water, least complex
except ammonia.
_Ammonia._ The simplest protein derivations.
From the discussion of the constituents in the milk and cheese, it is
evident that practically all the principal ripening changes are
concerned with those taking place in the proteins.
+236. Causes of ripening changes.+--Authorities disagree as to the exact
agents which cause the ripening changes. Some think they are due to the
action of the enzymes in the rennet and those secreted in the milk.
Others hold that these changes are due entirely to bacterial action. A
combination of the two seems probable. The action of the rennet extract
renders the casein insoluble and in the ripening process the proteins
become soluble, the degree depending on the length of time the cheese is
ripened. The amount of water-soluble proteins and protein derivatives is
used as a measure of the extent of cheese ripening, considered from a
chemical standpoint.
+237. Action of the rennet extract.+--Some authorities hold that rennet
extract contains two enzymes, rennin and pepsin, while others think it
is a single peptic ferment. These enzymes produce effects[108] closely
related to, if not identical with, those of pepsin in the following
particulars: neither the rennet enzyme nor pepsin causes much, if any,
proteolytic change except in the presence of acid; the quantitative
results of proteolysis furnished by the rennet enzyme and pepsin agree
closely, when working on the same material under comparable conditions;
the classes of soluble nitrogen compounds formed by the two enzymes are
the same, both quantitatively and qualitatively; neither enzyme forms
any considerable amount of amido compounds and neither produces any
ammonia; the soluble nitrogen compounds formed by both enzymes are
confined to the group of compounds known as paranuclein, caseoses and
peptones.
Rennet exerts a digestive effect on the casein[109] which is intensified
by the development of acid in the curd. The soluble nitrogenous products
formed in Cheddar cheese by the rennet enzymes are the albumoses and the
higher peptones. Experiments show that no flavor develops until the
amido acids and ammonia are formed. When the rennet enzymes were the
only digesting ferments in the cheese, there was no trace of cheese
flavor. This is probably due to the fact that the rennet enzyme changed
the casein into caseoses and peptones but did not form amido acids and
ammonia. Some authorities[110] think that the enzyme galactase carries
the ripening of the protein from this stage. The question arises whether
these intermediate compounds must be found before other agents can form
the amido acids and ammonia.
TABLE XV[111]
SHOWING THE EFFECT OF DIFFERENT AMOUNTS OF RENEET
EXTRACTS ON THE RATE OF FORMATION OF SOLUBLE
NITROGEN COMPOUNDS IN CHEESE RIPENING
=========================================================
| PER CENT OF WATER SOLUBLE NITROGEN
QUANTITY OF | COMPOUNDS IN THE CHEESE
RENNET ADDED PER +---------------------------------------
1000 LB. OF MILK | Initial | 32 days | 80 days | 270 days
-----------------+---------+---------+---------+---------
2 oz. | 0.14 | 0.47 | 0.68 | 1.30
4 oz. | 0.16 | 0.75 | 1.13 | 1.74
8 oz. | 0.16 | 0.90 | 1.50 | 1.97
16 oz. | 0.14 | 1.26 | 1.70 | 2.04
=========================================================
The above table shows that the more rennet extract used the faster the
cheese cures, measured by the amount of water-soluble nitrogen compounds
formed in the cheese.
+238. The action of the bacteria.+--Authorities[112] disagree as to the
groups of bacteria found in Cheddar cheese. This may be due to lack of
proper classification. Some of the groups are: _Bacterium lactis acidi_,
_B. coli communis_, _B. lactis aerogenes_, _B. casei_, Streptococci,
_B.[113] Bulgaricum_ and Micrococci. Authorities agree that the _B.
lactis acidi_ group is the most prominent. This group makes up 90 per
cent or more of the total bacteria flora of the cheese in the early
stages of ripening. In the course of a few weeks, however, this group is
largely replaced by the _B. casei_ group[114].
TABLE XVI
SHOWING THE NUMBER OF BACTERIA TO A GRAM IN CHEDDAR
CHEESE AS DETERMINED BY LACTOSE-AGAR PLATE CULTURES
====================================================================
TIME OF | CHEESE NUMBER
PLATING +-------------+---------------+-------------+--------------
| 580 | 581 | 582 | 583
---------+-------------+---------------+-------------+--------------
Milk | 8,000,000 | 500,000 | 700,000 | 500,000
---------+-------------+---------------+-------------+--------------
Curd at | | | |
salting | 160,000,000 | 326,000,000 | 912,000,000 | 839,000,000
time | | | |
---------+-------------+---------------+-------------+--------------
12 hours | 332,000,000 | 1,048,000,000 | 623,000,000 | 965,000,000
---------+-------------+---------------+-------------+--------------
1 day | 586,000,000 | 736,000,000 | 709,000,000 | 569,000,000
---------+-------------+---------------+-------------+--------------
2 days | 235,000,000 | 405,000,000 | 848,000,000 | 580,000,000
---------+-------------+---------------+-------------+--------------
4 days | 145,000,000 | 684,000,000 | 522,000,000 | 1,025,000,000
---------+-------------+---------------+-------------+--------------
6 days | 165,000,000 | 184,000,000 | 853,000,000 | 184,000,000
---------+-------------+---------------+-------------+--------------
14 days | 51,000,000 | 211,000,000 | 369,000,000 | 401,000,000
---------+-------------+---------------+-------------+--------------
21 days | 284,000,000 | 290,000,000 | 348,000,000 | 319,000,000
---------+-------------+---------------+-------------+--------------
28 days | 285,000,000 | 453,000,000 | 314,000,000 | 144,000,000
---------+-------------+---------------+-------------+--------------
35 days | 104,000,000 | 261,000,000 | 326,000,000 | 504,000,000
---------+-------------+---------------+-------------+--------------
49 days | 132,000,000 | 228,000,000 | 436,000,000 | 661,000,000
---------+-------------+---------------+-------------+--------------
70 days | 128,000,000 | 291,000,000 | 193,000,000 | 168,000,000
---------+-------------+---------------+-------------+--------------
98 days | 114,000,000 | 212,000,000 | 45,000,000 | 55,000,000
====================================================================
From Wis. Bul. 150.
The large number of bacteria in the cheese is very striking. The number
as given in the accompanying table is not that actually in the cheese,
as it is very difficult to obtain the sample in suitable condition for
plating.[115]
The principal action of the lactic acid-forming bacteria in the cheese
ripening is the changing of the milk-sugar or lactose into lactic acid
and the formation of small amounts of other substances, such as acetic,
succinic and formic acids, alcohol, aldehydes and esters and some gases,
carbon dioxide and hydrogen. While the amount of these substances other
than lactic acid is small, it is thought that the effect of these on the
cheese may be important. Heinemann shows[116] that lactic acid exists in
two optical modifications, the levorotatory and dextrorotary acids. In
cheese they are usually found in the inactive or racemic form, the
levorotatory and dextrorotary acids being present in equal amounts. What
importance the question of optical activity of the lactic acid may
assume is not definitely known. Just as some groups of bacteria have a
specific effect on the lactose, producing only one modification of
lactic acid, so bacteria attacking lactic acid may exercise a selective
action and use only one or the other optically active modification. In
other words, the early flora of cheese-ripening bacteria may determine
the later flora by the production of a form of lactic acid attacked by
one group of bacteria and not by another, and the effect on the flavor
will differ accordingly. The amount of lactic acid in the cheese
increases for a time, then decreases.
The errors in determining lactic acid are considerable. It seems that
the tendency is toward an increase of lactic acid in the cheese long
after the lactose has disappeared. Two explanations are offered: one,
that in the lactic acid fermentation an intermediate compound or
compounds are formed which exist for some time, the conversion into
lactic acid being complete at about three months; the other is that
lactic acid is formed as a product of paracasein proteolysis.
The lactic acid formed in cheese ripening does not exist in a free state
but reacts with the calcium salts in the cheese and forms calcium
lactates. It is thought that there is sufficient of these salts to
neutralize all the acid formed, and therefore the acid does not enter
into combination with the paracasein salts. It has been found that
lactates are the principal source of acetic and propionic acids. These
are supposed to have some effect on the flavor of the cheese.
The effect of lactic acid as a determinant of bacterial and enzymic
changes is very important. Early in the ripening process, lactic acid
suppresses the growth of undesirable micro-organisms. It also furnishes
the acid medium necessary for the best action of both the coagulating
and peptic enzymes.
The importance of the lactic acid bacteria in cheese ripening has been
summed up by Hastings[117] as follows: "The functions of this group of
bacteria in Cheddar cheese are through their by-product lactic acid as
follows: (_a_) To favor the curdling of milk by rennet. (_b_) The
bacteria of the milk are held in great part in the curd. Through the
acid they influence the shrinkage of the curd and expulsion of the whey,
(_c_) The acid so changes the nature of the curd as to cause 'matting,'
or 'cheddaring' of the curd, (_d_) The acid activates the pepsin of the
rennet extract, (_e_) The acid prevents the growth of putrefactive
bacteria in the cheese. (_f_) It has been shown that _Bacterium lactis
acidi_ is able to form acid in the absence of the living cell. (_g_) The
development of _Bacterium lactis acidi_ is followed by the growth of
another group of acid-forming bacteria, the _Bacillus Bulgaricus_ group.
They reach numbers comparable with those of the first group, reaching
their maximum number within the first month of ripening. Since they
develop after the fermentation of the milk-sugar, they must have some
other source of carbon and of energy than milk-sugar." It is also
probable that other groups constantly present contribute to the changes.
From the preceding discussion it is evident that each of the ripening
agents has its important part to play in the ripening process and a
normal ripening of the cheese is a composite result of these various
agencies.
+239. Conditions affecting the rate of cheese ripening.+--The rate at
which these agents cause ripening of the cheese depends on several
factors.[118] Most of these factors are within the control of man. They
are as follows: the length of time; temperature of the curing-room;
moisture-content of the cheese; size of the cheese; the quantity of salt
used; the amount of rennet; the influence of acid.
+240. The length of time.+--The water-soluble nitrogen compounds
increase as the cheese ages, other conditions being uniform. The rate of
increase is not uniform; it is much more rapid in the early than in the
succeeding stages of ripening.
+241. The temperature of the curing-room.+--Very few cheese factories
have made any provision for regulating the temperature of the
curing-room. Without such provision the temperature follows closely that
of the outside air. In some cases the curing-room is located over the
boiler-room and hence becomes very hot. In the cheese warehouses,
provision has been made to control the temperature very closely.
Experiments show that the soluble nitrogen compounds increase, on the
average, closely in proportion to an increase of temperature, when the
other conditions are uniform.
The temperature of the curing-room has a material effect on the quality
of the cheese. Cheese made from the same day's milk, and part cured at
40° F., part at 50° F., part at 60° F. show considerable differences,
the greatest seeming to be in the flavor and texture. Those kept at the
low temperature cure more slowly and develop a milder flavor, those at
the higher temperature cure faster and develop undesirable flavors. At
the higher temperature the undesirable organisms seem to be more active.
Some very skillful makers and judges of cheese have always contended
that if Cheddar is properly made, firmed to the body and texture of a
high-class cheese, ripening at 55 to 60° F. gives a higher quality. Such
a cheese must be low in moisture, perhaps 3 to 5 per cent lower than one
cured successfully by the cold process.
The following tables[119] XVII, XVIII show the effect of different
temperatures of curing cheese on the total score and on the points of
the flavor, body and texture:
TABLE XVII
TABLE SHOWING THE RELATION OF TEMPERATURE OF CURING
TO TOTAL SCORE
==========================================
TEMPERATURE OF CURING | TOTAL SCORE
----------------------+-------------------
40° | 95.7
50° | 94.2
60° | 91.7
==========================================
TABLE XVIII
TABLE SHOWING THE RELATION OF TEMPERATURE OF CURING
TO SCORE OF BODY AND TEXTURE, AND FLAVOR
=================================================
TEMPERATURE OF CURING | 40° F. | 50° F. | 60° F.
----------------------+--------+--------+--------
Body and texture | 23.4 | 32.0 | 22.2
Flavor | 47.4 | 46.4 | 44.8
=================================================
Of the three temperatures of curing, the lowest gave a higher total
score and a higher score for flavor, body and texture.
The curing temperature should not go low enough to freeze the cheese, as
this lowers the quality. The cheese will cure very slowly and have a
mealy texture.
+242. Moisture-content of the cheese.+--Other conditions being equal,
there is a larger amount of water-soluble nitrogen compounds in cheese
containing more moisture than in that containing less moisture.
Therefore, a high moisture-content of the cheese causes it to cure
faster. The presence of moisture also serves to dilute the fermentation
products which otherwise would accumulate and thus check the action of
the ripening agents.
+243. The size of the cheese.+--Cheeses of large size usually cure
faster than smaller ones, under the same conditions. This is due to the
fact that the large cheeses lose their moisture less rapidly by
evaporation and therefore after the early period of ripening have a
higher water-content.
+244. The amount of salt.+--The relation of salt to the rate of ripening
is more or less directly associated with the moisture-content of the
cheese, since an increase in the amount of salt decreases the moisture.
Thus, cheese containing more salt forms water-soluble nitrogen compounds
more slowly than that containing less salt. The salt also has a direct
effect in retarding one or more of the ripening agents.
+245. The amount of rennet extract.+--The use of increased amounts of
rennet extract in cheese-making, other conditions being uniform, results
in the production of increased quantities of soluble nitrogen compounds
in a given period of time, especially such compounds as paranuclein,
caseoses and peptones.
+246. The influence of acid.+--It is necessary that acid be present but
the exact relation of varying quantities of acid to the chemical changes
of the ripening process is not fully known. If too much acid is present,
it imparts a sour taste to the cheese. It also causes the texture of the
cheese to be mealy or sandy instead of smooth and waxy.
Conditions that may increase the rate of ripening:
1. Increase of temperature.
2. Larger amounts of rennet.
3. More moisture in the cheese.
4. Less salt.
5. Large size of the cheese.
6. Moderate amount of acid.
Conditions that may retard ripening:
1. Decrease of temperature.
2. Smaller amounts of rennet.
3. Less moisture in the cheese.
4. More salt.
5. Small size of the cheese.
6. No acid or an excess of acid.
+247. Care of the cheese in the curing-room.+--The cheeses need daily
attention while in the curing-room (Fig. 53). They should be turned
every day to prevent sticking and molding to the shelf and to secure an
even evaporation of moisture. If not turned, the moisture will not
evaporate evenly from all surfaces and will result in an uneven
distribution in the cheese, which causes uneven curing, and usually
gives the product an uneven color.
The surface of the cheese should be watched to see that the cloths
stick. If they do not, the surface will crack, due to the evaporation of
the moisture. If the cloths are loosened, they should be removed and the
surface of the cheese greased with butter. The grease will tend to
prevent the rind from cracking. If the surface of the cheese is not
smooth, due to wrinkles in the bandage, or if it cracks, due to the lack
of cloths, it furnishes the opportunity for insects to lay their eggs
and the larvæ to develop within the cheese. Molds also lodge and grow in
such cracks.
[Illustration: FIG. 53.--Cheddar cheese curing-room.]
The cheese should be kept clean while in the curing-room. This means
that the hands of the person handling the cheese must be clean. The
shelves should be washed with good cleaning solution and scalded with
hot water whenever they become greasy or moldy.
Some means should be provided for regulating the temperature and
humidity of the curing-room. In most factories this is accomplished by
opening the doors and windows at night to admit the cool air and closing
them in the morning to keep out the hot air. Care should be taken to
keep the doors and windows closely secured. The windows should have
shades to keep out the sun. If the room becomes too dry, the floor may
be dampened with cold water.
The length of time in the curing-room depends on how often shipment is
made to some central warehouse or to the market. This usually varies
from two to six weeks.
When the surface of the cheese becomes dry and the rind is well formed,
the cheese may be paraffined. It usually requires four to six days after
cheeses are taken from the hoop before they are ready for this process.
The object of paraffining is to prevent the escape of moisture and to
keep the cheese from molding.
+248. Evaporation of moisture from the cheese during ripening.+--The
losses due to evaporation while the cheeses are curing are a
considerable item. The rate of evaporation depends on the temperature
and humidity of the curing-room, the size of the cheese, the
moisture-content and protection to the surface.
Table XIX[120] shows the effect of size of cheese and temperature of the
curing-room, on losses while curing. This table shows that the
evaporation of moisture is more as the size of the cheese decreases and
the temperature is increased. This is probably due to the fact that the
smaller cheese has more surface to a pound than a large cheese. The
evaporation increases with temperature, probably because of lowered
relative humidity. The humidity can be tested with an hygrometer.
TABLE XIX
SHOWING THE VARIATION OF LOSSES IN WEIGHT OF CHEDDAR
CHEESE WHILE CURING, DUE TO SIZE OF CHEESE AND TEMPERATURE
OF CURING-ROOM
=============================================================
| WEIGHT LOST PER 100 POUNDS OF CHEESE IN 20
WEIGHT OF CHEESE | WEEKS AT
IN POUNDS +---------------+--------------+------------
| 40° F. | 50° F. | 60° F.
-----------------+---------------+--------------+------------
70 | 2.5 | 2.4 | 4.2
45 | 2.7 | 3.7 | 5.1
35 | 3.9 | 5.9 | 8.5
12½ | 4.6 | 8.1 | 12.0
=============================================================
The higher the moisture-content of the cheese, usually the more rapid is
the evaporation. This is due to several causes: there is more moisture
to evaporate; the moisture is not so well incorporated; a moist cheese
does not form so good a rind.
249. +Paraffining+[121] consists of dipping the cheese in melted
paraffin at a temperature of about 220° F. for six seconds. Fig. 54
shows an apparatus for paraffining. This leaves a very thin coat of
paraffin on the cheese; at a lower temperature, a thicker coat would be
left. The thicker coating is more liable to crack and peel off. If the
cheese is not perfectly dry before it is treated, the paraffin will
blister and crack off.
Before a cheese is paraffined, the press cloth is removed and also the
starched circles, if loose. After a cheese has been paraffined, if the
coating is not broken, the loss due to evaporation is greatly reduced.
The amount of paraffin to coat a 35-pound cheese will depend on the
temperature of the paraffin and the length of time the cheese is
immersed. Usually at 220° F. it requires about 0.15 of a pound for each
35-pound cheese. After the cheeses have been paraffined, they may be
left on the curing-room shelves or boxed ready to ship.
[Illustration: FIG. 54.--A paraffiner for cheese.]
+250. Shipping.+--When ready to ship, each cheese should be carefully
and accurately weighed and boxed. Usually these cheeses are boxed after
being paraffined. If press cloths are left on the cheese in the
curing-room, they should be removed just before weighing. These cloths
should not be left in a pile in the factory after being removed as they
have been known to heat and sometimes cause fires. They should be washed
clean and dried ready for use again. If starched circles are used, they
should be left on the cheese. A scale board should be placed on each end
of the cheese to prevent its sticking to the box and also to keep the
box from wearing the surface of the cheese.
The box should be a trifle larger in diameter than the cheese so that
the latter can be easily placed in it. The sides of the box should be
the same height as the cheese.
The weight of each cheese should be neatly and accurately marked on each
box. Care should be exercised to keep the boxes clean.
DEFECTS IN CHEDDAR CHEESE
A great number of defects may occur in Cheddar cheese. Certain of these
are due to known causes and proper remedies are definable, while neither
cause nor remedy has been found for other defects. Some of the common
defects and their causes and remedies are discussed under different
headings of the score-card as: defects in flavor, their causes and
remedies; defects in body and texture, their causes and remedies;
defects in color, their causes and remedies; defects in finish and their
causes and remedies.
+251. Defects in flavor.+--Any flavor differing from the characteristic
Cheddar cheese is a defect. Certain of these defective flavors can be
recognized and causes and remedies given for them, while others may be
distinguished as such but no cause or remedy can be given.
+252. Feedy flavors.+--Flavors may be characteristic of certain feeding
stuffs. Feeding strong-flavored foods, such as turnips, cabbage, decayed
silage, certain weeds and sometimes rank green feed, give their peculiar
flavors to both milk and cheese. Freshly drawn milk usually absorbs
these odors from the air in barns filled with such foods. Certain of
these materials may be fed just after milking in moderate amounts
without affecting the milk drawn at the next milking. Others should not
be used. Milk should not be exposed to strong volatile odors. Some of
the objectionable odors may be removed by airing the curd for a longer
time after milling before the salt is applied.
+253. Acid flavors.+--A cheese with an acid flavor has a pronounced sour
smell and taste. This is caused by the over-development of acid which
may be due to any of the following causes: (_a_) receiving milk at the
factory which is sour or has too high development of acid; (_b_) using
too much starter; (_c_) ripening the milk too much before adding rennet;
(_d_) not firming the curd sufficiently in the whey before removing the
latter; (_e_) developing too much acid in the whey before it is removed;
(_f_) retaining too much moisture in the curd.
The trouble can be reduced or eliminated by one or more of the following
precautions: (_a_) receiving only clean, sweet milk at the cheese
factory; (_b_) maintaining the proper relation between the moisture and
acidity; (_c_) adding the rennet at the proper acidity; (_d_) using less
starter; (_e_) adding the rennet extract so that there will be
sufficient time to firm the curd before the acid has developed to such a
stage that it will be necessary to draw the whey; (_f_) producing the
proper final water-content in the newly made cheese.
+254. Sweet or fruity flavors.+--These are the sweet flavors
characteristic of strawberry, raspberry and the like. Such flavors are
very objectionable and usually increase with the age of the cheese. They
appear to be caused by: (_a_) carrying both milk and whey in the same
cans without properly cleaning them; (_b_) exposing milk near hog-pens
where whey is fed; (_c_) dirty whey tanks at the cheese factory; (_d_)
micro-organisms which get into the milk through any unclean conditions.
These troubles can be controlled: (_a_) if milk and whey must be carried
in the same cans, the cans should be emptied immediately on arrival at
the farm and thoroughly washed and scalded; (_b_) the whey vat at the
factory should be kept clean and sweet; (_c_) the starter must have the
proper clean flavor.
Other defects may be classed as "off flavors," "dirty flavors," "bitter
flavors" and the like. These are undoubtedly due to unsanitary
conditions whereby undesirable organisms get into the milk, even though
the particular organism is often not determined. The flavors may be
improved by the use of a clean-flavored commercial starter and by airing
the curd after milling before salting. The best remedy is to remove the
source of the difficulty.
+255. Defects in body and texture.+--The body and texture should be
close. A sample rubbed between the thumb and fingers should be smooth
and waxy. Any condition which causes a body and texture other than this
is to be avoided.
+256. Loose or open texture.+--A cheese with this defect is full of
irregularly shaped holes and usually soft or weak-bodied. This is
serious if the cheese is to be held for some time. Moisture and fat are
likely to collect in these holes and cause the cheese to deteriorate,
thereby shortening its commercial life.
Several causes may bring about this condition: (_a_) insufficient
cheddaring; (_b_) pressing at too high a temperature; (_c_) inadequate
pressing; (_d_) development of too little acid.
The corresponding remedies are: (_a_) cheddar the curd until the holes
are closed and the curd is solid; (_b_) cool the curd to 80° F. before
putting to press; (_c_) press the curd longer, possibly twenty-four to
twenty-six hours; (_d_) develop a little higher acid in the whey before
removing the curd.
+257. Dry body.+--A cheese with this defect is usually firm, hard and
dry, sometimes rubbery or corky. This may result from lack of moisture,
fat or both, and may be due to the following causes: (_a_) making the
cheese from partly skimmed-milk; (_b_) heating the curd in the whey for
too long a time; (_c_) heating the curd too high; (_d_) stirring the
curd too much in the whey or as the last of the whey is removed; (_e_)
using too much salt; (_f_) developing of too much acid in the whey;
(_g_) curing the cheese in too hot or too dry a curing-room; (_h_) not
piling the curd high or fast enough in the cheddaring process.
The cause should be located and the corresponding remedy found, as
follows: (_a_) make cheese only from whole milk; (_b_) draw the whey
sooner; (_c_) firm the curd at as low temperature as possible in the
whey; (_d_) stir the curd in the whey only enough to keep the curd
particles separated but do not hand-stir it; (_e_) use less salt; (_f_)
develop less acid in the whey; (_g_) cure the cheese in a cool moist
curing-room; (_h_) pile the curd sooner and higher during the cheddaring
process.
The number of causes which may singly or in combination produce dry
cheese demands experience and technical skill that calls for the
development of a high degree of judgment.
+258. Gassy textured cheese.+--Gassy cheese has large numbers of very
small round or slightly flattened holes. When round these are called
"pin-holes," and when slightly flattened "fish eye" openings. These are
due to the formation of gas by the micro-organisms in the cheese. When a
cheese is gassy, it usually puffs up from gas pressure as in the rising
of bread. If enough gas is formed, it will cause the cheese to break or
crack open. Instead of being flat on the ends, such a cheese becomes so
nearly spherical as to roll from the shelf at times.
The gas-producing organisms enter because of unclean conditions
somewhere in the handling of the milk and the making of the cheese.
Some of the common sources of gas organisms are: (_a_) unclean milkers;
(_b_) dirty cows; (_c_) aërating the milk in impure air, especially air
from hog-pens where the whey is fed; (_d_) allowing the cows to wade in
stagnant water or in mud or in filthy barnyards and then not thoroughly
cleaning the cows before milking; (_e_) exposing the milk to the dust
from hay and feed; (_f_) dirty whey tanks; (_g_) drawing milk and whey
in the same cans without afterward thoroughly washing them; (_h_)
unclean utensils in the factory; (_i_) using gassy starter; (_j_)
ripening cheese at high temperatures.
Some of these causes are within the control of the cheese-maker after
the making process is begun. Many of them are avoided only by eternal
vigilance. Among the recommendations for meeting gassy curd are the
following: use only milk produced under clean sanitary conditions; use a
clean commercial starter.
If gas is suspected in the milk, a larger percentage of commercial
starter should be used. More acid must be developed before the whey is
removed. If the gas shows while cheddaring, the curd should be piled and
repiled until the holes flatten out before milling.
The curd should be kept warm during the piling or cheddaring process.
This may be accomplished by covering the vat and setting a pail or two
of hot water in it. After milling, the curd should be stirred and aired
for a considerable length of time before salting. This will aërate the
curd and allow it to cool. The cheese should then be placed in a cool
curing-room. (See handling of gassy milk.)
+259. Acidy, pasty or soft body and texture.+--A cheese with acidy body
may be either hard and dry or soft and moist. It has a mealy or sandy
feeling when rubbed between the fingers. The causes and remedies are the
same as for cheeses with acid flavors. When rubbed between the fingers,
it is pasty and sticks to the fingers. It is caused by the cheese
containing too much water. (See control of moisture.)
+260. Defects in color.+--Any color which is not uniform is a defect.
The proper color depends on the market requirement. Some markets prefer
a white and others a yellow cheese; however, if the color is uniform, it
is not defective.
_Mottled color_ is a spotted or variegated marking of the cheese.
Several causes may give the same general effect: (_a_) uneven
distribution of moisture, the curd having extra moisture being lighter
in color; (_b_) neglecting to strain the starter; (_c_) adding the
starter after the cheese color has been added; (_d_) mixing the curd
from different vats.
Remedies for this mottled color are: (_a_) to maintain a uniform
assimilation of moisture (see discussion of moisture); (_b_) to strain
the starter to break up the lumps before adding to the milk; (_c_) to
add all of the starter before adding the cheese color; (_d_) not to mix
curds from different vats.
_Seamy color._--In "seamy" colored cheese, the outline of each piece of
curd may be seen. There is usually a line where the surfaces of the curd
come together. It may be caused by the pieces of curd becoming greasy or
so cold that they will not cement. This may be remedied by having the
curd at a temperature of 80° to 85° F. when put to press. If it is
greasy, this may be removed by washing the curd in cold water.
_Acid color._--This is a bleached or faded color and is caused by the
development of too much acid. (See acid flavor for causes and remedies,
page 266.)
+261. Defects in finish.+--Defects of this class differ from those
previously mentioned in being entirely within the control of the
cheese-maker. All are due to carelessness or lack of skill in
manipulation. Anything which detracts from the neat, clean, workmanlike
appearance of the cheese is a defect that may interfere with the sale of
an article intrinsically good. Some of the common defects are: (_a_)
unclean surfaces or dirty cheese; (_b_) cracked rinds; (_c_) moldy
surfaces; (_d_) uneven sizes; (_e_) cracked cheese; (_f_) wrinkled
bandages; (_g_) uneven edges.
CHEDDAR CHEESE JUDGING
Judging of cheese is the comparison of the qualities of one product with
those of another. To make this easier it is customary to reduce the
qualities of the cheese to a numerical basis. This is accomplished by
the use of a score-card, which recognizes certain qualities and gives to
each a numerical value. Each of these score-cards gives a perfect cheese
a numerical score of 100. Two score-cards are used to judge cheese, one
for export and the other for home-trade product. The latter is more
commonly used.
EXPORT SCORE-CARD HOME-TRADE SCORE-CARD
Flavor 45 Flavor 50
Body and texture 30 Body and texture 25
Color 15 Color 15
Finish 10 Finish 10
--- ---
Total 100 Total 100
The same qualities are recognized in each score-card, but different
numerical values are given them.
+262. Securing the sample.+--The sample of cheese to be examined is best
obtained by means of a cheese-trier (Fig. 55). This is a piece of steel
about five or six inches long fitted with a suitable handle. It is
semicircular in shape, about ½ to ¾ of an inch in diameter. The
edges and end are sharpened to aid in cutting. This is inserted into the
cheese and turned around and then drawn out. It removes a long cylinder
of cheese, commonly called a "plug." This plug should be drawn from the
top rather than from the side of the cheese, because when the bandage is
cut it often splits, due to the pressure against it and so exposes the
cheese.
[Illustration: FIG. 55.--A cheese-trier.]
+263. How to determine quality.+--As soon as the plug has been removed,
it should be passed quickly under the nose to detect any volatile odors
which are liable to leave the cheese quickly. Next, the compactness of
the plug should be noticed and the color carefully examined. Then the
outer end of the plug should be broken off and placed back in the cheese
in the hole made by the trier. It should be about an inch long and
pushed in so that the surface of the cheese is smooth. This prevents
mold and insects entering the cheese. Usually the cheese will mold after
a short time where the plug has been removed. The remainder of the plug
should be saved for determining the flavor and the body and texture.
The flavor can be determined by the first odor obtained from the cheese
on the trier and by mixing or crushing a piece of the plug between the
thumb and fore-finger and then noting the odor. Mixing and thoroughly
warming causes the odor to be much more pronounced. The cheese should
seldom be tasted to determine the flavor, for when many are to be
judged, they all taste alike after the first five or six. This is
probably due to the cheese adhering to the teeth, tongue and other parts
of the mouth, making it difficult to cleanse the mouth sufficiently. The
body and texture can be determined by the appearance and the feeling of
the cheese when rubbed between the thumb and fingers. The body and
texture are distinct, yet they are more or less interchanged. The body
refers to the cheese as a whole and the texture to the arrangement of
the parts of the whole. The openness of texture or the holes can be
noted when the plug is first removed. The firmness of body and
smoothness of texture can be determined when the cheese is rubbed
between the thumb and fingers. The color can be judged when the plug is
first removed. The finish or appearance may be noted either before or
after the other qualities by carefully examining the cheese.
Cheddar cheese should have a neat, clean, attractive appearance; when
cut it should show a close, solid, uniformly colored interior. It should
have a clear, pleasant, mild aroma and a nutty flavor. It should possess
a mellow, silky, meaty texture and when rubbed between the thumb and
fore-finger should be smooth and free from hard particles.
CHEESE SCORE-CARD
_Sample_................ _Date_......................
===============================================================
SCORE REMARKS
---------+-----+----------+------------------------------------
Flavor | 50 | ........ |
| | |
Body and | | |
Texture | 25 | ........ |
| | |
Color | 15 | ........ |
| | |
Finish | 10 | ........ |
---------+-----+----------+
Total | 100 | ........ |
---------+-----+----------+
Recommendations................................................
...............................................................
...............................................................
...............................................................
...............................................................
...............................................................
...............................................................
...............................................................
Name of Judge.............................
---------------------------------------------------------------
SUGGESTIVE TERMS
FLAVOR
_Desirable_
Clean Pleasant Aroma Nutty Flavor
_Undesirable_
+Due to Farm Conditions+
Weedy Feedy Cowy Old Milk Bitter
+Due to Factory Conditions+
Too much acid Too little acid
+Due to either Farm or Factory Conditions+
Yeasty Fruity Fishy Rancid Sour Bitter Sweet Tainted
BODY AND TEXTURE
_Desirable_
Smooth Waxy Silky Close
_Undesirable_
Pasty Corky Acidy Greasy Loose Sweet Curdy
Gassy Watery Mealy Lumpy Yeasty Too dry
COLOR
_Desirable_
Uniform
_Undesirable_
Streaked White specks Seamy Mottled Wavy Rust spots
Acid cut Too high Too light
FINISH
_Desirable_
Clean surfaces Neat bandage Attractive
_Undesirable_
Wrinkled bandage Unclean surfaces Cracked rinds
Undesirable size Greasy No end caps Uneven edges
+264. Causes of variations in score.+--It is very seldom, if ever, that
a cheese is given a perfect score, for it usually has one or more
defects which may be hardly noticeable or very pronounced. The
seriousness of the defect is determined by the individual tastes of the
judges and the market requirements. It is customary for the judge to
pick out several samples and score them in order to fix the standard
and if there are several judges this serves to unify their standard.
Ordinarily judges will vary because of their individual tastes, unless
they begin with a uniform standard.
Certain markets require cheese with given qualities which on other
markets would be considered defects. For example, the Boston market
requires a very soft, pasty cheese which other markets would consider
undesirable.
The cheese is constantly undergoing changes due to the ripening agents
so that it may not always be scored the same. For example, a cheese may
have little or no flavor and after several weeks a very considerable
flavor may have developed. This is probably due to the action of the
ripening agents, and therefore the second time it would be scored
differently.
+265. The score-card.+--When judging several samples of cheese, the type
of score-card on the opposite page is used for each one.
This gives the date of judging and the sample number, the judge's name
and reasons for cutting the score and recommendations to avoid these
troubles.
CHAPTER XV
_THE SWISS AND ITALIAN GROUPS_
Certain varieties of hard cheese of foreign origin are now made to some
extent in this country. If not manufactured in sufficient quantities to
supply the demand, the remainder is imported. These hard cheeses are now
considered.
SWISS CHEESE
Swiss cheese, variously known as Gruyère, Emmenthal, Schweitzer and
Swiss, had its origin in the Alpine cantons of Switzerland. From this
region its manufacture has been carried by Swiss dairy-men and emigrant
farmers into widely separate lands. The Swiss colonies settled in the
United States in the Mohawk Valley and in Cattaraugus County, New York;
in Wayne, Stark, Summit, Columbiana and Tuscarawas counties of Ohio, and
in Green and Dodge counties in Wisconsin. Of all these, the Wisconsin
colonies have become the most extensive. Similar colonies have developed
the making of this type of cheese in Sweden and Finland.
+266. The Swiss factory.+--Swiss cheese cannot be made in a vat like
other types for reasons that will be explained later. In place of the
vat is used a kettle, generally of copper, and it may or may not be
jacketed for steam or for hot water (Fig. 56). These kettles vary in
capacity from 600 to 3000 pounds of milk. The cheese-maker takes the
best care possible of his kettle, for an unclean utensil is one of the
easiest sources of contamination of the milk. When the kettle is not
jacketed, and it is only in recent years that this has been done, it is
suspended in a fireplace by means of a crane arrangement.
[Illustration: FIG. 56.--Swiss-cheese kettle.]
This fireplace uses wood, and is built of brick or stone, so that the
kettle rests on the edge and is provided with a door which swings upon
another crane, and can be closed while the fire is going. When the
kettle is swung on a crane, it is possible to swing it under the
weigh-stand for filling. This requires a lid to swing down over the
fire, and keep the room free from smoke. The chimney generally has a
rather high stack to secure a good draft. This kettle is fastened to the
crane by a large iron band passing around the neck, to which a bail or
handle is attached. The kettle may be raised or lowered by means of a
simple screw on this beam. The crane consists of a heavy beam working in
sockets in the floor and a beam or cross brace, which has another and
shorter beam braced to it, to take the weight of the kettle.
The weigh-stand, and its efficient location, is a matter of extreme
importance. It is elevated a little above the remainder of the floor to
allow gravity to do the work. The next most important equipment is the
press and draining table. The table is made of wood or stone, and has a
slight slope to allow the whey to drain off. The press is generally a
jack screw which, braced against a beam, will exert an enormous pressure
on the table below.
Swiss cheeses are made in two styles, the "round" or drum and the
"block" or rectangular forms, each of which has its advantages. For the
round style, which is most commonly made, the forms for hooping are of
metal or of elm wood, and consist of strips of a given width, generally
six inches, but of an undetermined length. These strips are then made
into a circle and held by a cord, which is easily lengthened or
shortened, thus varying the diameter of the hoop.
Besides these hoops, cheese boards or followers are needed. These are
heavy circular boards, of a size to fit that of the cheese generally
made, and are banded with iron around the edge and cross-braced on the
bottom for rigidity. The small tools of the factory consist of knives to
cut the curd, and of a "Swiss harp" or other similar tool to stir the
curd. Many clean bandages are also needed, and a kettle brake.
+267. The milk.+--Swiss cheese requires clean sweet milk. Dirt, high
acid and infections with undesirable bacteria involve difficulties of
manufacture and frequent losses of cheese. One common practice rejects
milk if it shows acidity above 0.15 per cent. To secure milk in this
condition, factories are small and located so close to the producing
farms as to secure 1000 to 3000 pounds of milk delivered warm from the
cow twice a day. The cheese is made twice daily from this fresh milk.
If, however, milk is properly cared for, it is possible to mix night's
and morning's milk without bad results. In fact, in working
experimentally with high grade milk and taking precautions against loss
of fat, it has been necessary to skim (separate) part of the milk, thus
reducing the ratio of fat to casein. Analysis of good Swiss cheeses
shows that the desired texture is more uniformly obtained with milk in
which the fat is less than the normal ratio. This assumes that the
manufacturing loss is kept down so that the fat removed offsets the
extra loss from curd-breaking.
+268. Rennet extract.+--Most Swiss cheese-makers prefer to make their
own rennet extract from the stomach. This results in a product which is
not uniform in strength and so requires good judgment to secure the
desired coagulation in the allotted time. Some cheese-makers roll
fifteen to twenty well salted calves' stomachs together and dry them.
From this they cut off a definite amount each day to be soaked for
twenty-four hours in two to five quarts of whey at 86° F. Four quarts of
this solution added to 2000 pounds of milk at 90° F. should produce a
curd ready for cutting in twenty to thirty minutes.
+269. Starter.+--Makers do not agree as to the use of "starters" for
Swiss cheese. Those opposed to such use say that a starter will give the
cheese a decided Cheddar flavor, while those in favor of it state that
it will control undesirable fermentations, and that, with the use of a
starter, it is possible to make Swiss cheese throughout the year, and
have uniform success.
Doane,[122] working with _Bacillus Bulgaricus_ as a starter, found that
these starters did not always overcome the undesirable fermentations. If
a cheese-maker is having difficulty to develop the holes or "eyes," this
may be overcome by making a starter[123] as follows from good cheese and
whey or milk: Select a cheese which has the desirable "eyes" or holes
and a good flavor. Grind up some of this and add about ¼ of a pound
to one gallon of milk or whey. Hold this for twenty-four hours at a warm
temperature (85° to 90° F.). Strain it into the vat of milk just before
the rennet is added.
+270. The making process.+--The milk is delivered twice a day without
cooling. It usually reaches the factory at a temperature of 92° to 96°
F. It is strained into the kettle, and starter and rennet added at the
same temperature as received. (For method of adding rennet, see Chapter
V.) Enough rennet should be used to give a coagulation ready for cutting
in twenty to thirty minutes. The firmness of the curd is tested by
inserting the index finger in an oblique position, then raising it
slightly and with the thumb of the same hand starting the curd to break
or crack. When the curd is coagulated ready for cutting, it will give a
clear break over the finger.
It is important to keep the temperature uniform while coagulation is in
process, and this is best accomplished by the use of a little pan
arrangement which fits into the top of the kettle. When this is full of
water at 100° F., the temperature of the air above the milk will be
about 90° F. When the curd is ready for cutting, a scoop may be used and
the top layer carefully turned under to equalize the temperature more
closely.
_Cutting the curd._--In some cheese factories, knives resembling Cheddar
cheese knives are employed to cut the curd. In other factories, a "Swiss
harp" is used to break the curd. The curd is usually cut or broken into
pieces about the size of kernels of corn. The practice of "breaking"
curd instead of cutting it with sharp curd-knives produces excessive
loss at times. Experimental study has shown that the loss of fat may be
kept as low as 0.3 per cent if modern curd-knives are substituted for
the breaking tool formerly used. Study of Swiss cheeses of all grades
supports the opinion that the removal of a small part of fat from usual
grades of factory milk produces a better quality of product than the use
of rich whole milk. This may be accomplished through the escape of fat
in the whey on account of breaking the curd and stirring it vigorously,
or by skimming a part of the milk which is then curdled, cut and stirred
under such conditions as to minimize the loss of fat.
_Cooking the curd._--After cutting, the curd is stirred in the whey for
about twenty minutes before the steam is turned on and is then heated to
128° to 135° F. While this heating is in progress, constant stirring
must be given to avoid matting. This excessive stirring breaks the curd
up into pieces about the size of wheat kernels, and accounts for the
large fat loss, which is one of the main sources of loss in making Swiss
cheese. This stirring is accomplished by a rotary motion, and the use of
a brake, which is a piece of wood closely fitting the side of the
kettle. This creates an eddy in the current at that point and gives a
more uniform distribution of temperature. The process of cooking takes
from thirty to forty minutes, and at the end of that time the degree of
toughness may be determined by making a roll of curd in the hand, and
noticing the break when it is given a quick flip. A short sharp break
indicates the desired toughness.
_Draining and hooping._--In this process, the cheese-makers' skill is
displayed. With the hoop prepared, and the curd at the correct stage of
toughness, the operator takes a press cloth, wets it in whey, slips it
over a flexible iron ring which can be made to fit the shape of the
kettle, gives the contents of the kettle a few swift revolutions, then
suddenly reverses the motion, with the result that the contents form
into a cone, and the ring and bandage are dexterously slipped under this
cone, and drawn up to the surface of the whey with a rope or chain and
pulley. This part of the process is the most important, as a cheese must
have a smooth firm rind, else it will quickly crack. With too large a
batch of milk, the curd can be cut into two pieces and hooped
separately. With the mass of curd at the top of the whey, the piece of
perforated iron plate just the size of the hoop is slipped under the
mass, and attached to the pulley by four chains. Then the top of the
mass is carefully leveled off, because while still in the whey, it
cannot mat badly and so tend to develop a rind crack. Now the mass is
raised clear of the whey, and run along a short track to the drain
table, where it is put in the press.
_Pressing._--The mass of curd is dropped into the hoop, the edges of the
cloth carefully folded under, and the cloth laid on top, then the
pressure is applied, gradually at first, but increasing until the final
pressure is about fifteen to twenty pounds to a pound of cheese.
During the first few hours the cloths must be changed frequently, and
the cheese carefully turned over each time, to secure a more uniform
rind. After a time the changes are less frequent, and at the end of
twenty-four hours the cheese is taken to the salting-room.
_Salting_ may be done by either the brine or dry method. To prepare a
brine bath, add salt to a tank of water until it will float an egg, and
add a pailful or more of salt every few days thereafter to keep up the
strength. The cheese is then placed in this bath and left for three to
five days, depending on the saltiness desired. As the cheese floats with
a little of the rind above the surface, it should be turned a few times
to insure uniformity of salting. With dry salting, the salt is rubbed on
the cheese by hand or with a stiff brush, and any excess carefully wiped
off, leaving only a slight sprinkle on the surface to work into the
cheese.
+271. Curing Swiss.+--From the salting-room, the cheese goes to the
first one of two curing-rooms, where the unique process of the
development of the characteristic eyes takes place.
During the curing period of either round or block Swiss, constant
attention must be paid to the cheese. They must be turned every day at
first, and then every second or third day toward the end of the curing
period. Also, great care must be taken that no mold starts growing, as
it will soon work into the cheese, and spoil its flavor. The best way of
preventing mold is by washing the cheese, in either clean or slightly
salted water, as often as possible. A stiff brush is mostly used for
this.
The development of the "eyes" or holes is the difficult part of the
whole process. It is not known exactly what causes the development, but
it is attributed to micro-organisms or enzymes. The gas in these eyes
has been examined and found to be carbon dioxide and free nitrogen.
Sometimes hydrogen is found. This comes from the original fermentation
of the milk-sugar and remains to contaminate the normal eye. The
nitrogen[124] is included from the original air. Propionic acid is
formed at the same time as the eyes, and they are said to be the result
of a propionic ferment of lactic acid. The interior of the cheese is
anaërobic, due to low permeability and high oxygen-absorbing quality.
This propionic bacterium cannot, however, account for all the carbon
dioxide produced.
After the eyes have started, their further development depends on
temperature and humidity of the air, and on the moisture of the cheese,
as regulated by the amount of salt used. The first room has a
temperature of 70° F. to start the eyes, which is later lowered in the
second curing-room to about 60° to check the development. When any local
fermentive action starts, it may be checked by rubbing salt on the
affected part. The humidity of the room is very important, because a
cheese will quickly dry out in a dry room, due to evaporation from the
surface. To prevent this, it is well to spray the floor with water, or
to have a steam jet in the room.
If the curd has been cooked too long the cheese may be too dry. Such
cheeses may be piled two or more deep in the curing-room. It is held by
some cheese-makers that this process causes them to absorb more
moisture. Probably this is due to the checking of evaporation.
The development of the "eyes" may be watched by trying the following
test: Place the middle finger on the cheese and let the first finger
slip from it, striking the cheese smartly; a dull sound indicates
solidity, while a ring indicates a hole, and an expert maker can tell
the size of the holes by the sound. This requires long practice for the
operator to become proficient.
After a cheese has remained in the first room for about two weeks and
the holes are well started, it is removed to the second curing-room,
which is held at a cooler temperature and slightly drier atmosphere. The
cheeses are held in this room from three to ten months, depending on
market conditions, and capacity of the curing-rooms. In Switzerland, it
is customary to hold cheese to secure a well ripened product, while in
America most of the cheeses are shipped comparatively green, hence do
not bring so high a price.
+272. Block Swiss.+--In making block Swiss, the same procedure is
followed through the cooking stage. Then the curd is pressed in a square
form or in one large piece, each form six inches square on the ends and
twenty inches long, and later cut into sections. These are then pressed,
salted and cured in the same way as round forms. In this type of cheese
there is a much smaller cross-section; therefore the development of
holes is much more easily controlled on account of the ease with which
the salt can work into the cheese and control undesirable ferments. As
it is easy to control, this variety is made in the fall and winter when
the ferments are especially hard to keep in check. However, this cheese
has the disadvantage of cutting eye-development short by the rapid
entrance of salt.
The curing consists of the developing of the flavor and eyes and the
changing in body and texture. Just what causes these changes is not
known.
+273. Shipment.+--When ready for shipment, the drum cheeses of the same
general diameter are sorted out and packed four to six in a cask. Care
must be taken to put boards between them to prevent sticking. These are
called scale-boards, and are made of thin sections of wood fiber. The
cheeses are crowded into the cask to make a snug fit, and the head
carefully fastened.
+274. Qualities of Swiss cheese.+--The peculiar Swiss cheese flavor may
be characterized as a hazel-nut taste. It is a trifle sweet and very
tempting. The "eyes" or holes should be about the size of a cherry with
a dull shine to the inner lining. The "eyes" usually contain a small
amount of a briny tasting liquid. These eyes should be uniformly
distributed. The color should be uniform. The cheese should have a neat,
clean, attractive appearance, and the rind should not be cracked or
broken.
There are several common defects in Swiss cheese. If the milk is not
clean-flavored, the cheese will have the same flavor as the milk. The
greatest difficulty is to produce the eyes or holes. A cheese which does
not have these is called "blind." A product which has many small
pin-holes due to gassy fermentations is called a "niszler"; this means a
cheese with a thousand eyes. If gas forms in the cheese and causes
cracks, it is called "glaesler." If the cheese contains too much
moisture, it will be soft and pasty. Such a cheese does not readily form
eyes.
+275. Composition and yield.+--A large number of analyses of Swiss
cheese have been made but there is wide variation. This is due to the
fact that the composition and yield are both dependent on the following
factors: composition of the milk, losses during manufacture, amount of
moisture in the cheese. The losses in Swiss cheese are much larger than
with some of the other hard cheeses, such as Cheddar. This is because
more fat is lost in the whey, due to breaking instead of cutting the
curd and the subsequent hard stirring. The possibility of reducing these
excessive losses has already been indicated.
Swiss cheeses of high grade show about the following range of
composition:
Water 30-34 per cent
Fat 30-34 per cent
Protein 26-30 per cent
Ash 3-5 per cent
Salt (NaCl) 1-1.4 per cent
The water-content of this type of cheese is low and the protein-content
is proportionately high. Both conditions lead to firm textures, long
ripening and long keeping periods.
The following score-card is used to judge both block and drum Swiss
cheese:
Flavor 35
Appearance on trier holes 30
Texture 20
Salt 10
Style 5
----
100
The yield of Swiss cheese varies from 8 to 11 pounds to 100 pounds of
milk. The more solids in the milk, the more moisture incorporated in
the cheese; the smaller the loss of solids in the manufacturing process,
the larger will be the yield from a given amount of milk.
THE ITALIAN GROUP[125]
A group of varieties, best known in America by Parmesan, are made in
Italy with related forms in Greece and European Turkey. These forms are
very hard, usually uncolored, with small eyes or holes. They are made in
large cheeses which ripen very slowly. Cow's milk is regularly used for
Parmesan and Grana in northern Italy; other varieties contain goat or
sheep milk or various mixtures. Aside from Parmesan, few of the other
forms are known outside the place of origin except as they are exported
in a small way to satisfy the demand of emigrants from these regions.
+276. Parmesan.+--One type of Italian cheese, however, the Parmesan, has
become very widely known. In general the consuming trade does not
discriminate between Parmesan, Grana and closely related forms. Parmesan
is made in large cheeses which require one to three years for proper
ripening; in texture it is very hard with small eyes or holes formed by
very slow fermentation. Such cheeses are ripened in large storehouses in
which hundreds and even thousands are brought together and cared for by
experts. The surfaces of these cheeses are kept clean and free from
insects by rubbing with linseed oil. So hard are these forms that the
cheese-trier is not used in testing, but the texture of the surface is
tested by pricking with an awl-like tool and the stage of eye-formation
and associated ripening is determined by the sound given out when the
cheeses are tapped with a hammer.
When ripe, the cheeses of this group are used in cooking principally.
The broken cheese is grated and added to macaroni, spaghetti and other
cooked cheese dishes. Parmesan is usually made from partly skimmed-milk;
the ratio of fat to protein in analysis runs from 1:2 to 3:4 in contrast
to the normal relation of about 4:3 in whole-milk cheese. In
water-content much variation is found, but ripe Parmesan is usually
about 30 per cent water. Other members of the group are made with
different amounts of skimming, some of them from whole milk. The group
in general represents the requirements of cheese for the trade of warmer
regions (see Mayo and Elling): (1) a low fat-content so incorporated
that the cheese does not become greasy or oily in hot weather; (2) a
water-content low enough to prevent rapid spoilage during the necessary
exposure of handling under warm conditions.
The equipment for Parmesan manufacture has more resemblance to that of
the Swiss factory than the English and American cheeses. The milk is
curdled in deep copper kettles (Fig. 57), below which there is commonly
a provision for direct heating by fire which is sometimes carried on a
truck, and therefore can be withdrawn when heating is sufficient. The
steam-jacketed kettle has replaced this earlier form to a large measure.
[Illustration: FIG. 57.--Parmesan cheese kettles.]
The general character of the manufacturing process is indicated in the
following abstract of one of the methods. Many variations are to be
found. The milk for Parmesan is allowed to stand overnight. Some acidity
is, therefore, developed in contrast to the absolutely fresh condition
of the milk used in Swiss and the acidification developed during the
making of Cheddar (Fascetti). It is then skimmed, heated to 72° to 75°
F. Rennet is added in amount sufficient to produce firm curd in one hour
or slightly less. When the curd is firm, a wood fire is made under the
kettle and the curd is broken with a special implement into small
particles. After breaking, four grains of powdered sulfur to twenty-two
gallons of milk are added. The curd is stirred with a rake. By the time
the temperature rises to 77° F., the curd should be in very small
pieces. Stirring and heating continue until the temperature reaches 131°
F. At this temperature, it stands fifteen minutes, after which it is
removed from the fire (or the fire is drawn). Nine-tenths of the whey is
then drawn. The cheese-maker then collects the curd into a compact lump
under which he slips a cheese cloth. With the aid of an assistant he
removes the mass to a perforated vessel for draining. After this the
curd goes into large wooden hoops, lined with cloth, which stand upon a
slanting draining table until evening. No pressure is used. Before
night they are taken to the cellar. The cloths are removed next day.
After standing four days, they are salted by covering the upper surface
with coarse salt. This is repeated with daily turning for twenty days,
then salted on alternate days for another period of twenty days. At the
end of the forty days' salting, the cheese is removed from the hoop,
scraped, sprinkled with whey and the rind rubbed smooth. A dressing of
linseed oil either with or without bone black is applied.
[Illustration: FIG. 58.--A typical cheese-market in France.]
The cheeses are kept in special ripening rooms, and rubbed frequently
with linseed oil to keep the surfaces free from molds and vermin.
Careful grading as to quality of product and consequent response to
ripening conditions produce cheeses of many degrees of excellence.
Those in which a ripening of three to four years is possible are most
highly esteemed.
+277. Regianito.+--A cheese of the Italian group is now made in
Argentina and imported to the United States under the name Regianito.
CHAPTER XVI
_MISCELLANEOUS VARIETIES AND BY-PRODUCTS_
As already discussed in Chapter VI, there are a large number of
varieties of cheese. Very many are entirely unknown in America. A
considerable number of forms are occasionally imported and may be found
by visiting the markets and delicatessen stores in the foreign districts
of our large cities. Certain forms not widely known are made in America
in a few factories or are imported in sufficient quantity to call for
brief discussion. Some of these are brought together here.
The importance of the by-products of cheese-making has not been
sufficiently recognized, for manufacture on a large scale is only
beginning to be appreciated in America. Certain cheese names, such as
Mysost, are applied to whey products. In addition, milk-sugar is
extensively made and whey-butter has been carefully studied and found to
be practicable under some conditions.
+278. Caciocavallo+ originated in Italy, but is now made in certain
factories of New York and Ohio. Some factories in Lombardy[126] use
whole milk, others use half-skimmed milk. The latter practice is
probably the more common. In making this cheese, the milk is coagulated
with rennet, cut and firmed in the whey, allowed to settle and the whey
drawn. The curd is then piled on the draining table and allowed to mat
or fuse into fairly solid masses. After several hours of draining and
matting, the curd is cut into strips and placed in a vat of hot water.
In the hot water, the blocks of solid curd melt into taffy-like masses
which are worked and molded by hand into more or less standard shapes.
Indian club or ten-pin forms are most commonly produced. When the proper
shape has been gained, each mass is thrown into cold water which
solidifies it in that form. Cheese masses heat and cool slowly; several
hours of cooling are required to insure a firm cheese. The newly made
cheeses are salted in a brine bath, then hung by a string to ripen.
Sometimes these cheeses are eaten fresh, again they are ripened several
months. They vary in size from one to six pounds. Cornalba gives the
composition of Italian Caciocavallo made from whole milk as water 32 to
34 per cent, fat 34 to 36 per cent, protein 28.5 to 29.5 per cent, salt
1.7 to 1.8 per cent; when made from half skimmed-milk, water 28 per
cent, fat 27 to 28 per cent, protein 35 to 40 per cent, salt 2.2 per
cent. Other analyses vary widely from these figures on account of the
differing fat-content of the milk. No standardized practice has been
established in America.
_Provolono_ resembles Caciocavallo in method of manufacture and
composition, the main difference being in the shape of the cheese. It is
more or less round and is held by a coarse net made of small rope. The
cheeses are treated while curing the same as Caciocavallo.
+279. Sap sago.+--This hard green cheese imported from Switzerland is
made in cakes, tapering from perhaps two inches in diameter to a rounded
top with a height of about two inches. These are made from skimmed-milk
curd, partially ripened then mixed with powdered leaves of _Melilotus
coeruleus_, a clover-like plant. The mixture is then pressed into the
market form and dried until very hard. It is handled without special
care since the water-content is so low that fermentations are
exceedingly slow. This low-priced cheese may be used in cooking.
+280. Albumin cheese.+[127]--In the rennet cheeses, the albumin, which
constitutes about 0.7 per cent of the milk, passes off in the whey. This
albumin is not curdled by rennet. It is, however, coagulated by heating.
The presence of acid hastens such coagulation but does not cause it when
used alone. When the whey is heated to about 200° F., the albumin rises
and may be skimmed off. In this form it is recovered and used. It may be
shaped is hoops under pressure, as Ricotte, an Italian form. This cheese
is pressed firmly and dried. Such albumin is frequently prepared as a
poultry feed.
+281. Mysost, Norwegian whey cheese.+--The whey contains nearly 5 per
cent of milk-sugar which can be recovered by boiling. The Norwegian
process which produces Mysost consists in raising the whey to the
boiling point, skimming off the albumin as it rises, then concentrating
the remainder of the whey. As it reaches sufficient concentration, the
albumin is thoroughly stirred back into the mass and the mass finally
cooled into forms. Mysost is a brown, hard brittle mass consisting
principally of caramelized milk-sugar. Analysis shows such percentage
composition as follows: water 10 to 20 per cent, protein 10 to 15 per
cent, milk-sugar 30 to 55 per cent. Mysost is found in the larger
markets of the United States.
_Primost_ is an albumin cheese somewhat similar to Ricotte and Mysost.
It is made by precipitating the albumin by acid and heat. The main
difference is in the firmness of the cheese. This is regulated by
drying.
+282. Whey butter.+[128]--The loss of a percentage of fat, rarely less
than 0.3 per cent and in some cheeses very much greater, has led to the
making of whey butter. For this purpose a separator is introduced and
all whey is separated daily. The fat recovered in the form of cream is
then ripened and churned. Whey butter is not rated as equal to butter
made from whole milk but a fair market can usually be found for the
product. The recovery of 0.25 per cent fat means two and one-half pounds
of fat to 1000 pounds of whey. This will make about three pounds of
butter.
Whether whey butter shall be made depends on the volume of business, the
extra equipment required, the extra help necessary and the market for
the product. As a rule, whey butter is economically recoverable only in
large factories. It is not considered advisable to attempt to make it
unless one has the whey from 10,000 pounds of milk. In some instances,
the combination of small cheese factories with one churning plant has
proved to be economical. The objection to the making of whey butter is,
that it stimulates carelessness on the part of the cheese-maker because
he thinks that the fat will be recovered by skimming. He does not
realize that the other milk solids are being reduced in the same
proportion as the fat, to the great loss in yield of cheese.
CHAPTER XVII
_CHEESE FACTORY CONSTRUCTION, EQUIPMENT, ORGANIZATION_
The principal factor in determining the location of a cheese factory is
the available supply of milk. This is usually ascertained by making a
canvass, and finding out the number of cows whose milk would be brought
to the factory. The quantity of milk or the number of cows necessary to
insure sufficient milk for the successful operation of the factory,
depends on the variety of cheese to be made. When making types of cheese
for which very sweet milk is necessary, the milk must be delivered twice
a day. This demand limits the area from which the factory can secure its
supply. The length of time the cheeses are held in the curing-room and
the work necessary to care for them also limits the area which the
factory can serve, because a very large amount of milk cannot be handled
when the cheese must be given considerable attention in the
curing-rooms. Swiss, Limburger and Brick cheese factories usually do not
require a large supply of milk; therefore the factories may be built
close together. The size of the Cheddar cheese factories varies but it
is generally considered unprofitable to make Cheddar cheese unless there
are 5000 pounds of milk available daily. Conditions have changed so that
at present different kinds of cheese are made from the surplus milk in
market milk plants. In such cases a uniform supply is not absolutely
necessary. The climate must also be suitable for the industry.
+283. Locating the site.+--In a farming community, several factory sites
are usually available. It is best to consider carefully the desirable
features of each before trying to make a definite choice. Many of the
present cheese factories were located in hollows because it was easy to
secure a supply of water, but no thought or attention was given to the
disposal of the sewage. The following points should be considered in
choosing a site:
(1) _Drainage._--A factory should be so located that it has good
drainage. Ground that slopes away from the factory makes the disposal of
sewage easy. Sewage should not be allowed to run out on the ground and
left to decay, thus forming a breeding place for flies, but should run
into a cesspool or septic tank.[129] Even in a porous soil, a cesspool
frequently clogs and gives trouble. The septic tank seems to be the best
method to dispose of the sewage unless the factory is so located that
connection can be made with a city sewage system.
(2) _Water._--An abundant supply of pure water is essential to a
factory. This may come either from deep wells or springs. The value of a
never-failing water supply cannot be overestimated.
(3) _Exposure._--The factory should be so located that the receiving
room is away from the prevailing winds. This prevents dust being blown
into the factory. The curing-room should be on the side not exposed to
the sun as this will keep it cool. Fig. 59 shows a clean cheese factory
of the ordinary type. When it is desirable to cure the cheese in a
cellar, it is better to locate the factory on the side of a hill. Then
the receiving and manufacturing room may be on the ground level and the
curing-room, a cellar, back of the manufacturing room and yet all on
the same level. This saves carrying the cheese up and down stairs.
(4) _Accessibility to market_ should not be overlooked. Often the
quality of the cheese is injured by long hauls. An important item in
marketing both milk and cheese is the use of the automobile. By its use
the products are not so long in transit, and losses from exposure in
delivery are reduced. Both milk and cheese, when exposed to the heat of
the sun for any length of time, become warm. This gives undesirable
organisms chance to develop.
[Illustration: FIG. 59.--A cheese factory of neat appearance.]
+284. The building.+--Details of construction or estimates of cost will
be omitted in the present discussion. A local contractor can do this
satisfactorily and also the cost of materials is constantly changing.
Only general considerations as they apply to the manufacture of the
product will be taken up.
The building may be constructed of wood, stone, various bricks or
concrete. The kind of material will depend on the relative cost of
materials in the local market and on the amount of money available for
building.
+285. Heating plant.+--Many of the older factories have no heating
plants and some are so poorly constructed that they cannot be warmed.
Means of heating should be provided, either by steam or a stove. The
loss due to freezing is an item which is entirely avoided in factories
properly heated.
+286. Curing-rooms.+--The size of the curing-rooms will depend on the
amount of cheese to be handled and its location on the variety of cheese
to be manufactured. In every case, some provision should be made to
control humidity and temperature. If the room becomes hot and dry,
evaporation from the cheese will be much more rapid. In a hot
curing-room, undesirable types of ferments are more likely to develop
and to injure the quality of the cheese.
+287. Light.+--The importance of light should be emphasized. It acts as
a stimulant to keep things clean. It also makes the factory more
cheerful. There should be numerous windows to give plenty of light. A
skylight may often serve both as a source of light and ventilation.
+288. Ventilation.+--Plenty of ventilation should be provided. This may
be accomplished by means of the windows or skylight. However, it is a
good precaution to have at least one ventilator to carry off the steam
and control the circulation of air. All openings should be carefully
screened to keep out flies.
+289. Boiler-room.+--The boiler-room should be easily accessible from
the manufacturing rooms. A gauge located in the latter should tell the
steam pressure. Windows or doors should be so located that the flues of
the boiler can be cleaned. The coal supply should be handy. Great care
should be exercised to keep the boiler-room clean for otherwise the dirt
will be tracked all over the factory.
+290. Whey tanks+ should be kept clean. Daily washing is absolutely
necessary to prevent offensive odors. Pasteurization of whey has been
found requisite to prevent the spread of disease if raw milk is
used.[130] This is required by law in some states. It is sometimes
accomplished by heat with steam coils; in other cases by running live
steam directly into the whey. Whey tanks may be made of wood or steel.
The acid of the whey seems to eat and decompose concrete.
+291. Store-room.+--There should be a separate room or a place in the
attic where the supplies can be kept. This saves much waste and keeps
the factory cleaner and more tidy.
+292. The floors.+--The floor is the most important part of the
building. It should be of non-absorbent material, which can be easily
cleaned, and it should not leak. Concrete makes the best floor of any
material used at present. It should slope very gently to the drain. The
corners between the floor and side walls should be rounding to make
cleaning easy. The drain should be provided with bell traps to prevent
the entrance of sewer gas into the factory. If the traps and floor about
them are slightly depressed, it will help to make the floor drain more
quickly. A catch-basin should be provided just outside the factory for
all solid material which might clog the sewer pipe. This should be
cleaned three or four times a year.
[Illustration: FIG. 60.--A well arranged Cheddar cheese factory,
including the equipment for the manufacture of whey butter.]
+293. Arrangement of machinery and rooms.+--The rooms and machinery
should be arranged so that the work will follow the natural sequence of
the process with as little inconvenience as possible. Some of the points
to be observed in this connection are: vats should be near the
weigh-can; boiler-room near the work room; cheese presses near the vats;
cheese presses near the curing-rooms and the like.
Fig. 60 shows a well arranged Cheddar cheese factory. The necessary
machinery and rooms for the manufacture of whey butter are included. In
this plan, the attic contains the store-room and the whey tanks. The
whey is forced from the vats into the tanks with a steam jet and then
runs by gravity to the separator. Slides are provided in the walls of
the ice storage to regulate the flow of air into the curing-room and
butter refrigerator. In order to have a smaller boiler, a gasolene
engine is used to run the separator, churn and curd-mill. The plan can
be modified to use the upstairs for a curing-room so that the size of
the factory may be reduced. The whey butter could be shifted to a small
room where the curing-room now is and the boiler-room added as a
"lean-to" at one side of the building. This would materially reduce the
size of the main building.
Another plan (Fig. 61) shows the arrangement of a Cheddar cheese factory
without the whey butter apparatus. The location of the drain between the
vats might be criticized. In Fig. 62 is shown the arrangement of a
combined butter and cheese factory. Fig. 63 shows the possible
arrangement of a Limburger factory. The size of this factory could be
reduced by having the salting tables closer together.
In a Cheddar cheese factory, the curing-room may be over the
manufacturing room. This makes considerable work in carrying the cheese
up and down. A small elevator may be used for this purpose. The same
principle holds in cheese factories in which other varieties of cheese
are made; the floors should be on one level so far as possible. There
is danger of the overhead curing-room becoming too hot and causing the
cheese to leak fat. Shelves or tables should be provided on which to
put and keep the utensils. The utensils should never be placed on the
floor.
[Illustration: FIG. 61.--Plan of Cheddar cheese factory without whey
butter equipment. 1, Boiler; 2, sink; 3, hot water barrel for scalding
utensils; 4, cheese vats; 5, 6, cheese presses; 7, weigh-can; 8, desk;
9, Babcock tester; 10, shelf; 11, paraffine tank; 12, cheese shelves.]
[Illustration: FIG. 62.--Combined Cheddar cheese and butter factory.
1, Boiler; 2, engine; 3, water pump; 4, work bench; 5, wash sink; 6,
press; 7, elevator; 8, cheese vats; 9, separator; 10, milk heater; 11,
milk receiving vat; 12, press; 13, shelf; 14, Babcock tester; 15,
weigh-can; 16, churn; 17, starter; 18, cream ripener and pasteurizer;
19, refrigerator; 20, milk sheet and sample jar; 21, milk pump.]
+294. Arrangements for cleanliness.+--A sink for washing the utensils
should be provided and boiling water to scald them after washing. After
being scalded, tin utensils dry quickly without rusting. The boiling
water may be obtained by placing a steam pipe in a barrel of water and
turning on the steam. The utensils can then be washed clean, dipped in
this barrel of boiling water and put in their place. Too much emphasis
cannot be laid on keeping the factory itself, the utensils and the
surroundings clean. This will prevent the development of mold. Cases are
known in which the cheese factory was allowed to become very dirty, so
that a red mold developed. This eventually got into the cheese and
caused red spots.[131] They are called rust spots. All doors and windows
should be screened to keep out flies.
[Illustration: FIG. 63.--A Limburger cheese factory.]
+295. Equipment and supplies list.+--The following utensils will be
needed in a Cheddar cheese factory to handle 10,000 pounds of milk
daily: 1 5-H. P. boiler; 1 60-gallon weigh-can; 1 conductor head and
trough; 1 platform scale; 1 Babcock tester, glassware and sample
bottles; 2 700-gallon cheese vats; 2 gang cheese presses; 1 curd-mill; 2
curd-knives; 30 cheese hoops; 1 whey strainer; 1 curd scoop; 1
long-handled dipper; 1 strainer dipper; 1 siphon; 1 cheese knife; 1
glass graduate; 1 cheese-trier; 1 speed knife; 1 paraffine tank; 1
Marschall rennet test; 1 lactometer; 1 milk can hoist; 1 acid test; 1
sink; 1 40-quart milk can; 3 pails; 3 shot-gun cans for starter; 3
thermometers; brushes and brooms; 1 Wisconsin curd test or fruit jars
for same; 1 set counter scales; 2 curd rakes.
If whey butter is made, the equipment should include: Tanks to hold the
whey; separator; cream ripening vat; churn; butter-worker; butter
refrigerator; large boiler and steam engine or gasolene engine.
The following supplies will be needed for the making of the cheese:
Bandages; boxes; scale boards; starched circles; rennet extract or
pepsin; cheese color; press cloths; paraffine; formaldehyde; alkali;
indicator; sulfuric acid.
[Illustration: FIG. 64.--A sanitary dipper with a solid handle.]
When choosing the utensils, the ease of cleaning and sanitary
construction should not be overlooked. One of the most unsanitary
utensils in a factory is a dipper with a hollow handle. Fig 64 shows a
dipper with a solid handle which any tinsmith can make. The seams of all
utensils should be flushed full of solder, to make cleaning easy. When
ready to clean or wash any utensils which have come in contact with milk
or its products, the steps are as follows: rinse in cold water, wash in
warm water in which some washing-soda has been dissolved, rinse clean,
scald in boiling water. Never use a cloth to wash utensils; a brush is
more sanitary.
+296. Factory organization.+--There are two general classes of
organizations[132] to operate cheese factories, one the proprietary and
the other the coöperative. Unless the kind of organization is what the
dairy-men desire, dissatisfaction is sure to result.
(1) _Proprietary organization._--Under this form of organization, one
person owns and operates the factory. The dairy-men are paid a stated
price for milk, or the milk is made into cheese for a stated price a
pound. The proprietor receives all profits and assumes all losses.
So far as the dairy-man is concerned, the stock company is a proprietary
organization. The gains and losses are shared by each member according
to the amount of money invested.
(2) _Coöperative organization._--In a true coöperative cheese factory
each patron is an owner, as the name indicates. The object of this
organization is to reduce the cost of manufacture rather than pay large
dividends, so that the dairy-man with a large herd and small capital
invested in the factory obtains more returns than the one who owns
considerable capital and has a small herd. Many cheese factories are
coöperative in name only and proprietary in operation. The state of
Wisconsin has a law which tends to stop this defect and defines what
organizations may use the term or name, coöperative.
The constitution of a coöperative organization should state: 1, Name; 2,
object; 3, officers and duties of officers; 4, manager or other person
to run business; 5, capital stock; 6, meetings; 7, voting power; 8,
amendments.
Some of the most important statements which should appear in the
constitution are mentioned in the following sentences. A statement
should show what persons are eligible to membership in the organization.
It is a careless plan simply to say that the duties of the officers are
those usually defined in such an organization. This may lead to
confusion and neglect, or both. Direct statements should be made
explaining the exact duties of each officer. The limits of the authority
of the manager or person who runs the business should be explicitly
stated. The manager then knows just what his duties are and what matters
or parts of the business must be considered by other officers or
committees. The amount of capital stock and the number and value of each
share should be exactly stated. The constitution should state when and
where the regular meetings must be held and by whom and when special
meetings may be called. This gives every member ample notice of the
regular meetings. Some method or means should be provided to notify each
member of the special meetings.
The voting power should be definitely stated, whether it is limited to
shares of capital stock or by members or by number of cows owned by each
member. It is necessary to indicate just how amendments to the
constitution may be made. Each member should know before the final vote
just what changes are being proposed. Types of constitutions may be
found in the following references:
ELLIOTT, W. J., Creameries and cheese factories;
organization, building and equipment, Mont. Exp. Sta. Bul.
53, 1904.
FARRINGTON, E. H., and G. H. BENKENDORF, Organization and
construction of creameries and cheese factories, Wis. Exp.
Sta. Bul. 244, 1915.
VAN SLYKE, L. L., and C. A. PUBLOW, The science and
practice of cheese making, pages 447-453, 1909.
Iowa Exp. Sta. Bul. 139, 1913. Creamery organization and
construction.
CHAPTER XVIII
_HISTORY AND DEVELOPMENT OF THE CHEESE INDUSTRY IN AMERICA_
Just when the first cheese was made is not known. By the time the first
immigrants came to America, cheese-making was rather generally known in
Europe, so that the early settlers brought with them and practiced
established methods. The countries of Europe developed different kinds
of cheese and have since become noted for such particular varieties, for
example: France, Camembert and Roquefort; Switzerland, Swiss cheese;
England, Stilton and Cheddar; Germany, Limburger; Holland, Edam and
Gouda; Italy, Parmesan and its allies, also Gorgonzola cheese. The
manufacture of these various cheeses has been attempted in this country.
Because of the difference in climatic conditions and in some cases the
use of milk of sheep or goats, it was and still is difficult to
manufacture some of the European cheeses in America. Since the climatic
conditions of this country and certain parts of England are somewhat
similar, the manufacture of the cheeses of England predominated, and
there was also more information on their manufacture. These are probably
the reasons why the United States and Canada have become famous for
Cheddar cheese.
The first cheeses of the Cheddar group were made on the farms. The work
was usually performed by women, and the process was very simple. The
methods were crude, and the cheeses were made in a more or less
haphazard way. The milk of the evening was placed in a cheese tub in the
dairy room and cooled to a temperature that would prevent souring. In
most cases the cream that had raised to the surface of the night's milk
was removed in the morning. This was considered an act of economy, for
it was thought that in the process of manufacture it would all pass off
in the whey and be lost. The morning's milk was then mixed with that of
the evening and warmed to the setting temperature by placing a portion
in a tin pail and suspending it in a kettle of hot water. When hot, it
was emptied into the tub of cold milk. By transferring back and forth,
the setting temperature was finally reached. Few of these settlers owned
thermometers. Consequently, cheese-makers were obliged to depend on the
sense of feeling to determine temperature.
One of the serious difficulties of the early manufacture was the
production of rennet of a uniform strength. After the addition of the
rennet and as soon as the coagulated milk became firm enough, it was
broken into as small pieces as could be conveniently made, a wooden
knife being used for the purpose. After standing ten minutes it was
stirred by hand, breaking the pieces finer, and the temperature was
gradually brought to 98° F., aiming as near blood heat as could be
judged by the sense of feeling. It was kept at this temperature until
the moisture was out of the curd and it would squeak between the teeth.
The whey was drawn off and the curd stirred until dry, salted and put to
press. All the curd of one day was made into a cheese. This resulted in
small uneven-sized cheese. Since such cheeses were made from the milk of
single dairies with all the surroundings clean, the flavor was usually
good but the texture was open and soft. The method of caring for the
cheese and marketing was entirely different from that practiced at the
present time. All the cheeses made during the entire season were held
until fall and marketed at one time. They were packed in casks four to
six in a package, one on top of the other. The earliest date when single
boxed cheeses were on the market was 1841.
Between 1820 and 1840, a small export trade in cheese was started. As
this demand for cheese increased, particularly in England, it became
necessary to change the methods employed in manufacture. The farm dairy
cheese was rather an open-textured sweet curd product. If not, it was
due more to accident than to any intention of the cheese-maker to
improve the quality. One of the early complaints from England was that
the cheeses were too small and uneven in size. The practice of making on
the farm continued until about 1851, when the factory system was
started, although home manufactures continued after that time. Following
are the reasons for the change from the farm to factory system: (1)
England demanded larger cheese; (2) the farm product was not uniform;
(3) the quality of the farm cheese did not suit the English trade; (4)
factories saved much labor on the farms; and (5) could secure higher
prices.
+297. The factory system.+--Where and by whom the first Cheddar cheese
factory in America was started is not definitely known. Jesse Williams
of Oneida County, New York, is supposed by many to have been the first
to build and operate under the factory system, in 1851. Cheese factories
were opened in Ohio and Wisconsin about 1860. In the period 1860 to
1870, a large number of cheese factories were built in the various
states, especially New York, Ohio and Wisconsin.
+298. Introduction of factory system in Canada.+--In 1863, Harvey
Farrington of Herkimer, New York, was so impressed with the opportunity
of developing the cheese factory system in Canada that he sold out his
business in New York and established the first Canadian cheese factory
in the town of Norwich, Ontario. It was accepted at once by Canadian
farmers, and factory cheese-making increased rapidly. In 1866, a small
quantity of cheese was exported and from that time the export trade of
Canada has been large and growing. Ontario and Quebec are now the
leading provinces in the production of cheese.
+299. Introduction of cheddaring.+--The factories at first used the same
process as the farms, namely the stirred-curd process. In 1867, Robert
McAdam introduced the English Cheddar system in a factory near Herkimer,
New York. This is the Cheddar system as known to-day. It produces the
closer bodied cheese demanded by the export trade. This introduction
made Herkimer County famous for its cheese.
+300. Introduction of Swiss and Limburger.+--In 1870, factories for
Limburger, Swiss and Brick cheese were started and have gradually
increased. In New York such plants are located around Boonville in
Oneida County, and Theresa, in Jefferson County. In Wisconsin, Swiss
cheese-making was begun by a colony of Swiss who came to New Glarus,
Green County. It is now made in Green, Lafayette, Iowa, Grant, Dane and
Rock counties. Limburger and Brick are manufactured in Dodge, Fond du
Lac, Winnebago, Marathon, La Crosse, Buffalo, Trempealeau, Clark,
Washington, Dunn, Barron and Lincoln counties. In the southeastern part
of Ohio Swiss cheese is produced. Ohio and Wisconsin have manufactured
more of these cheeses, especially Swiss, than any other states. This is
probably due to the fact that the conditions are more nearly like those
of Switzerland.
When the cities in New York began to grow, an increased demand for
market milk was felt. The result was that the dairy-men could not supply
both the cities and the cheese factories with milk. A large part of the
cheese was being exported and most of it had always been partly skimmed.
The amount of skimming, therefore, was largely increased. Then other
animal fats were substituted for the milk-fat. This product was known as
"filled" cheese. The delay in controlling the practice of making
skimmed-milk and filled cheese ruined the export trade. In Canada laws
prohibited the making of filled cheese and as a consequence Canadian
Cheddar cheese is still very popular in England. However, with the
control of skimmed-milk cheese-making and the elimination of filled
cheese, the volume continued to grow and to find outlet in local
consumption. New York probably exported more cheese than any other
state. Wisconsin shipped cheese into other regions, especially the
southern states in which no cheeses were made. Some Wisconsin cheeses
were shipped to the New York market from time to time, but in October,
1913, the first quotations[133] were made in New York City for Wisconsin
products.
+301. Number and distribution of cheese factories.+--The following list
and maps (Figs. 65, 66) compiled in 1914 by the United States Department
of Agriculture Dairy Division, show the number of cheese factories in
the different states and their location:
[Illustration: FIG. 65.--Map showing the distribution of cheese
factories in the principal cheese-producing states.]
Arizona 3
California 93
Colorado 8
Connecticut 2
Delaware 1
Illinois 50
Indiana 13
Iowa 25
Kansas 1
Maine 5
Michigan 196
Minnesota 74
Missouri 4
Montana 1
Nebraska 1
New Hampshire 2
New York 995
North Dakota 3
Ohio 111
Oklahoma 1
Oregon 42
Pennsylvania 106
South Dakota 1
Utah 8
Vermont 35
Virginia 3
Washington 15
West Virginia 1
Wisconsin 1720
----
3520
+302. Total production of cheese in the United States.+--The following
figures (Table XX) compiled by the United States Census show the total
production of cheese and the amount made on farms and in factories in
the United States by ten-year periods:
TABLE XX
SHOWING THE TOTAL PRODUCTION OF CHEESE AND PART
MADE ON FARMS AND IN FACTORIES IN THE UNITED
STATES BY TEN-YEAR PERIODS
1849 Total 105,535,893 pounds
1859 Total 103,663,927 pounds
1869 Total 162,927,382 pounds
1879 Total 243,157,850 pounds
1889 On farms 18,726,818 pounds
In factories 238,035,065 pounds
Total 256,761,883 pounds
1899 On farms 16,372,330 pounds
In factories 281,972,324 pounds
Total 298,344,654 pounds
1909 On farms 9,405,864 pounds
In factories 311,126,317 pounds
Total 320,532,181 pounds
Comparing the figures of 1899 with those of 1909, it is seen that the
total production of cheese in the United States increased 22,187,539
pounds, or an increase of 7.4 per cent in 1909 over 1899. During the
same years the amount made on the farms decreased 6,966,454 pounds, or a
decrease of 42.6 per cent, while the amount made in factories increased
29,153,933 pounds or 10.3 per cent.
+303. Rank of the leading cheese-producing states.+--The rank of the
leading cheese states according to the number of factories in 1914 was:
Wisconsin 1720, New York 995, Michigan 196, Ohio 111, Pennsylvania 106.
[Illustration: FIG. 66.--Showing the cheese factories in the Pacific
coast states.]
The table on the opposite page (Table XXI) shows the amount of cheese
produced by the five states with the largest number of factories. This
table indicates that New York led in the production of cheese until some
time between 1899 and 1909. This is probably because, New York having so
many cities, the demand for market milk is so large that it is sold as
such instead of being manufactured into cheese. There is about the same
number of milch cows in New York and Wisconsin. However, Wisconsin is
credited with more cheese in 1909 than New York ever produced and this
output probably will increase, as there are considerable areas of
undeveloped agricultural land in Wisconsin. It is also interesting to
note that Ohio is falling off in cheese production. This may be due to
the increased demand for market milk. On the other hand, production has
increased in Pennsylvania.
TABLE XXI
SHOWING THE AMOUNT OF CHEESE MADE IN FIVE LEADING STATES
BY TEN-YEAR PERIODS
----------+----------+-----------+-----------+-----------+
STATE |YEAR 1859 |YEAR 1869 |YEAR 1879 |YEAR 1889 |
----------+----------+-----------+-----------+-----------+
|Amount in | Amount in |Amount in |Amount in |
| pounds | pounds | pounds | pounds |
| | | | |
| | | | |
| | | | |
Wisconsin | 1,104,300| 3,288,581| 19,535,324| 54,614,861|
| | | | |
New York |48,548,289|100,776,012|129,163,714|124,086,524|
| | | | |
Michigan | 1,641,897| 2,321,801| 3,953,585| 5,370,460|
| | | | |
Ohio |21,618,893| 24,153,876| 32,531,683| 22,254,054|
| | | | |
Penn | 2,508,556| 2,792,676| 8,966,737| 5,457,897|
----------+----------+-----------+-----------+-----------+
----------+-----------+-----------+-----------+
STATE |YEAR 1899 |YEAR 1909 |YEAR 1914 |
----------+-----------+-----------+-----------+
|Amount in |Amount in |Amount in |
| pounds | pounds |pounds from|
| | |factories |
| | |only |
| | | |
Wisconsin | 79,384,298|148,906,910|205,920,915|
| | | |
New York |130,010,584|105,584,947| 97,614,024|
| | | |
Michigan | 10,753,758| 13,673,336| 13,267,145|
| | | |
Ohio | 19,363,528| 12,473,834| 8,717,996|
| | | |
Penn | 11,124,610| 12,676,713| 14,808,573|
----------+-----------+-----------+-----------+
+304. Exportation and importation of cheese by the United States.+--The
accompanying table shows the exports and imports of cheese from 1851 to
1916 and their values, in so far as the figures are available.
[Illustration: FIG. 67.--Showing relationship of total production,
exports and imports of cheese.]
One noteworthy item in Table XXII is that the exports have gradually
decreased and imports increased. This is probably because immigrants
have demanded the cheeses of their native country which were not made in
America. The exports for the years 1915 and 1916 are interesting as they
show the effect of the war on the cheese industry, the imports being
gradually decreased and the exports greatly increased.
TABLE XXII
SHOWING THE IMPORTS AND EXPORTS OF CHEESE BY THE
UNITED STATES FROM 1851-1916
------+----------------------+--------------------------
YEAR | IMPORTS | EXPORTS
------+-----------+----------+-------------+------------
| Amount | | Amount |
| in | Value in | in | Value in
| pounds | dollars | pounds | dollars
| | | |
1851 | 603,398 | ---- | 10,361,189 | ----
1852 | 514,337 | ---- | 6,650,420 | ----
1853 | 874,949 | ---- | 3,763,932 | ----
1854 | 969,417 | ---- | 7,003,974 | ----
1855 | 1,526,942 | ---- | 4,846,568 | ----
1856 | 1,384,272 | ---- | 8,737,029 | ----
1857 | 1,400,252 | ---- | 6,453,072 | ----
1858 | 1,589,066 | ---- | 8,098,527 | ----
1859 | 1,409,420 | ---- | 7,103,323 | ----
1860 | 1,401,161 | ---- | 15,515,799 | ----
1861 | 1,090,835 | ---- | 32,361,428 | ----
1862 | 594,822 | ---- | 34,052,678 | ----
1863 | 545,966 | ---- | 42,045,054 | ----
1864 | 836,127 | ---- | 47,751,329 | ----
1865 | 985,362 | ---- | 53,154,318 | ----
1866 | ---- | ---- | 36,411,985 | ----
1867 | 1,738,657 | ---- | 52,352,127 | ----
1868 | 2,997,994 | ---- | 51,097,203 | ----
1869 | ---- | ---- | 39,960,367 | ----
1870 | ---- | ---- | 57,296,327 | ----
1871 | ---- | ---- | 63,698,867 | ----
1872 | ---- | ---- | 66,204,025 | ----
1873 | ---- | ---- | 80,366,540 | ----
1874 | ---- | ---- | 90,611,077 | ----
1875 | ---- | ---- | 101,010,853 | ----
1876 | ---- | ---- | 97,676,264 | ----
1877 | ---- | ---- | 107,364,666 | ----
1878 | ---- | ---- | 123,783,736 | ----
1879 | ---- | ---- | 141,654,474 | ----
1880 | ---- | ---- | 127,553,907 | ----
1881 | ---- | ---- | 147,995,614 | ----
1882 | ---- | ---- | 127,989,782 | ----
1883 | ---- | ---- | 99,220,467 | ----
1884 | 6,243,014 | ---- | 112,869,575 | ----
1885 | 6,247,560 | ---- | 111,992,990 | ----
1886 | 6,309,124 | ---- | 91,877,235 |
1887 | 6,592,192 | ---- | 81,255,994 |
1888 | 8,750,185 | ---- | 88,008,458 |
1889 | 8,207,026 | ---- | 84,999,828 |
1890 | 9,263,573 | ---- | 95,376,053 |
1891 | 8,863,640 | ---- | 82,133,876 |
1892 | 8,305,288 | ---- | 82,100,221 |
1893 |10,195,924 | ---- | 81,350,923 |
1894 | 8,742,851 | ---- | 73,852,134 |
1895 |10,276,293 | ---- | 60,448,421 |
1896 |10,728,397 | ---- | 36,777,291 |
1897 |12,319,122 | ---- | 50,944,617 |
1898 |10,012,188 | ---- | 53,167,280 |
1899 |11,826,175 | ---- | 38,198,753 |
1900 |13,455,990 | ---- | 48,419,353 |
1901 |15,329,099 | ---- | 39,813,517 |
1902 |17,067,714 |$2,551,366| 27,203,184 |$2,745,597
1903 |20,671,384 | 3,183,224| 18,987,178 | 2,250,229
1904 |22,707,103 | 3,284,811| 23,335,172 | 2,452,239
1905 |23,095,705 | 3,379,600| 10,134,424 | 1,084,044
1906 |27,286,866 | 4,303,830| 16,562,451 | 1,940,620
1907 |33,848,766 | 5,704,012| 17,285,230 | 2,012,626
1908 |32,530,830 | 5,586,706| 8,439,031 | 1,092,053
1909 |35,548,143 | 5,866,154| 6,822,842 | 857,091
1910 |40,817,524 | 7,053,570| 2,846,709 | 441,017
1911 |45,568,797 | 7,920,244| 10,366,605 | 1,288,279
1912 |46,542,007 | 8,807,249| 6,337,559 | 898,035
1913 |49,387,944 | 9,185,184| 2,599,058 | 441,186
1914 |63,784,313 |11,010,693| 2,427,577 | 414,124
1915 |50,138,520 | 9,370,048| 55,362,917 | 8,463,174
1916 |30,087,999 | 7,058,420| 44,394,301 | 7,430,089
------+-----------+----------+-------------+------------
The graph (Fig. 67) represents the total production and the exports and
imports of cheese into the United States.
+305. Average yearly price of cheese.+--The following table shows the
average yearly price of Cheddar cheese in the United States:
TABLE XXIII
SHOWING THE AVERAGE YEARLY PRICE OF CHEESE, 1892-1916
YEAR CENTS
1892 9.4
1893 9.4
1894 9.7
1895 9.1
1896 8.4
1897 9.1
1898 8.6
1899 8.6
1900 10.2
1901 9.9
1902 10.1
1903 11.9
1904 10.5
1905 10.7
1906 11.7
1907 11.6
1908 12.9
1909 12.6
1910 15.5
1911 12.4
1912 14.2
1913 17.0
1914 17.1
1915 15.3
1916 16.7
The graph (Fig. 68) shows that the average yearly price has increased
from 9.4 cents a pound to 16.7 cents.
[Illustration: FIG. 68.--Average yearly price of cheese.]
+306. Canadian cheese statistics.+--The following statistics show the
development of the industry in Canada. The figures in Table XXIV show
the number of cheese factories, the amount of milk received and the
total production in Canada.
Table XXIV indicates that the number of cheese factories has decreased
but that the production has increased. Because of the scarcity of
figures, conclusions would not be accurate.
The figures in Table XXV of the exports and imports show that the
exports gradually decreased and the imports increased. If the production
has increased, as shown in Table XXIV, more cheese must be consumed by
the Canadians. The effect of the war is probably seen in the year 1916,
when the imports are decreased and the exports increased.
TABLE XXIV
SHOWING THE NUMBER OF CHEESE FACTORIES, AMOUNT OF
MILK RECEIVED AND THE FACTORY PRODUCTION OF
CHEESE
-------+------------+---------------+---------------
| NUMBER OF | POUNDS OF | FACTORY
YEAR | CHEESE | MILK | PRODUCTION
| FACTORIES | DELIVERED | OF CHEESE
-------+------------+---------------+---------------
1900 | ---- | ---- | 220,833,269
| | |
1907 | ---- | ---- | 204,788,583
| | |
1910 | 2291 | ---- | 199,904,205
| | |
1915 | 1871 | 1,501,946,221 | 183,887,837
| | |
1916 | 1813 | 1,503,997,215 | 192,968,597
-------+------------+---------------+---------------
TABLE XXV
SHOWING THE AMOUNT AND VALUE OF CANADIAN EXPORTS AND
IMPORTS OF CHEESE
------+--------------------------+----------------------
Year | Exports | Imports
------+-------------+------------+-----------+----------
| Amount in | Value in | Amount in | Value in
| pounds | dollars | pounds | dollars
------+-------------+------------+-----------+----------
1880 | 40,368,000 | $3,893,000 | |
| | | |
1890 | 94,260,000 | 9,372,212 | |
| | | |
1900 | 185,984,000 | 19,856,324 | |
| | | |
1910 | 180,859,000 | 21,607,692 | 683,778 | ----
| | | |
1911 | 181,895,000 | 20,739,507 | 866,653 | ----
| | | |
1912 | 163,450,000 | 20,888,818 | 919,189 | ----
| | | |
1913 | 155,216,000 | 20,697,000 | 1,495,758 | ----
| | | |
1914 | 144,478,000 | 18,866,000 | 1,512,108 | ----
| | | |
1915 | 137,601,000 | 19,213,000 | 1,162,456 | ----
| | | |
1916 | 168,961,000 | ---- | 971,821 | ----
------+-------------+------------+-----------+----------
If the total population of the United States is figured at 100 million
and the difference between the exports and imports found and added to
the total production, it shows that the average person must consume
about three and one-half pounds of cheese in a year.
In the past few years there has been considerable demand for more of the
foreign cheeses, such as Camembert and Roquefort.
+307. Introduction of cheese-making into new regions.+--The manufacture
of Cheddar cheese is being encouraged in new regions, in the Alleghany
Mountains, in Virginia, West Virginia, North Carolina, Tennessee and in
the western states. There has also sprung up a considerable demand for
the lactic acid group of cheeses, especially Neufchâtel and Cottage, so
that while the cheese industry may decline in certain sections, the
total production will probably increase. In the proper locations or
sections, the cheese industry has a very bright future. The development
of the skimmed-milk cheeses will undoubtedly be given considerable
attention in the next few years.
REFERENCES
N. Y. Dept. Agr. Bul. 54, The Dairy Industry in New York State.
N. Y. Produce Rev. and American Creamery.
Vol. 34, No. 3, page 108.
Vol. 37, No. 16, page 684.
Vol. 37, No. 16, page 666.
Vol. 37, No. 9, page 411.
Vol. 33, No. 11, page 482.
Vol. 36, No. 23, page 1078.
Wis. Exp. Sta. Rept. 1897, pages 113-149.
U. S. Census.
U. S. Dept. Agr. Year Books.
Bureau of Foreign and Domestic Commerce.
Statistical abstract of the U. S.
Canadian Dept. Agr. 1915, Report of the dairy and cold storage
commissioner.
Dominion of Canada, Census and Statistics office, Rept. 1915.
CHAPTER XIX
_TESTING_
In connection with marketing, a certain amount of testing of the
products should be practiced, to determine exactly the results and
grades of products. This includes the testing of the whole milk, whey
and cheese for fat, the milk for casein, and the cheese for moisture. In
factories in which the milk is bought on the fat basis, it is necessary
to test each patron's milk for fat. If there is a cheese-moisture law in
the state, it is necessary to test for moisture. The whey should be
tested to learn the loss of fat in the manufacturing process and to
ascertain whether the losses have been reduced to the minimum.
+308. The fat test.+--The test commonly used to determine the fat in
milk is known as the Babcock. The principle of this test is as follows:
Fat exists in the form of very small globules. Because the fat globules
are lighter than the other milk constituents, under the influence of the
force of gravity most of them rise to the surface. There, mixed with the
other milk substances, these globules form a layer of cream. Babcock
found that by adding to the milk sulfuric acid of proper strength and
temperature, the casein, the milk-sugar and the albumin are decomposed
and the sticky quality of the milk is destroyed. The acid does not
decompose the fat but leaves it free to come to the surface of the
mixture. Under centrifugal force, this fat is quickly brought to the
surface. By using a known quantity of milk and having a scale graduated
in percentage of the amount of milk, the percentage of fat can be
determined. Fig. 69 shows the necessary equipment.
[Illustration: FIG. 69.--Apparatus necessary to test milk and whey for
fat and total solids.]
There are three kinds of bottles employed in making the test, one with a
very large neck which is used when testing materials high in fat-content
such as cream, butter and cheese. This is generally called a cream-test
bottle. It is graduated from 0 to 50 per cent. When testing materials
with a small amount of fat such as whey, skim-milk and buttermilk, a
test bottle with two necks is used, one with a small bore for the fat
and the other neck with a larger bore to add the milk, acid, water. It
is graduated from 0 to 0.5 of 1 per cent. There is a third bottle
between the other two to test whole milk. This is known as a whole-milk
bottle. It is graduated from 0 to 8 per cent. All of the glassware
should comply with the laws.
+309. Sampling the milk.+--One of the most important parts of testing is
to obtain a fair sample of the milk. The milk to be tested may be in a
vat or in a farmer's can or a composite sample jar. If the milk is
bought on the fat basis, that of each patron is not tested daily, but a
small quantity, about half an ounce, is taken each day and placed in a
jar; this is known as a composite sample. It is the usual practice to
number the patrons and have a sample bottle for each patron with his
number on it. Some substance must be added to preserve the milk and to
keep it from souring or coagulating. It is difficult to secure a fair
sample of sour milk. A wide-mouthed jar is preferred for keeping milk
samples. This must be kept closed to prevent evaporation. Each day when
milk is added to the composite sample, the bottles should be shaken to
prevent the cream drying. Composite samples are tested at least twice a
month. The milk may be mixed to obtain a fair sample, by stirring in the
vat or by pouring from one bottle to another. Vigorous shaking should be
avoided as this is likely to cause churning. One should see that all the
cream is removed from the sides of the sample bottle and that it is
evenly distributed through the milk. The sample of milk is now measured
out with the pipette. This is graduated to deliver 18 grams of milk, and
holds 17.6 c.c. Hold the pipette between the thumb and second finger of
the right hand with the tip below the surface of the milk, draw the milk
by suction with the lips until it is filled well above the graduation.
Quickly place the forefinger over the opening and at right angles to the
pipette. By gently and carefully raising the forefinger, allow the milk
to run down until the surface is exactly level with the graduation. To
obtain an accurate reading, the pipette should be on a level with the
eye. Then with the left hand, hold the milk test bottle in a slanting
position and place the tip of the pipette into it about one-third of an
inch and at a slight angle. Now let the milk slowly flow down the side
of the neck of the bottle, making certain that none is blown out by the
escaping air. When all has run out of the pipette, blow out the drop
which remains in the tip. Then measure out another sample in the same
way, as the test should be made in duplicate.
+310. Adding the acid.+--The sulfuric acid should have a specific
gravity between 1.82 and 1.83. It should be kept in glass-stoppered
bottles or carboys to prevent the absorption of moisture from the air,
which will reduce its strength. Acid that is too strong might burn the
fat. The acid is a strong poison and will burn if it comes in contact
with the flesh or the clothing. In such case, it should be removed by
washing with plenty of water. An alkaline substance such as ammonia or
bicarbonate of soda should be applied to remove any acid not washed
away.
The acid measure holds 17.5 c.c. and it should be filled to the
graduation. Then this acid should be added to the test bottle. The
bottle should be held at an angle and slowly rotated so that the acid
will rinse down any milk remaining in the neck of the bottle.
Immediately mix the acid and milk by whirling the body of the bottle in
a circle five or six inches in diameter. The mixture should not be
allowed to go into the neck of the bottle while mixing. Continue shaking
for about a minute after all the curd has disappeared. One should avoid
pointing the neck of the bottle toward any person in the mixing
operation. The acid unites with all the milk substances except the fat
and generates much heat.
+311. Centrifuging.+--There are two machines in common use for
centrifuging, one that runs by mechanical power and the other smaller
and runs by hand. If the machine and atmosphere are very cold, the
apparatus can be warmed by placing hot water in it. This is not
necessary in a steam machine. In a factory where there are a number of
samples to test, a power machine is usually employed. In this machine
there are pockets or cups in which to set the test bottles. The machine
or disk must be balanced by placing bottles in opposite pockets. These
pockets are hinged so that when standing still the bottle is in an
upright position and when the centrifuge is running, it is in a
horizontal position. The machine should then be covered and started
running. It should be run at the speed indicated. After five minutes,
stop the machine and fill the bottles with boiling water up to the neck.
This can be done without taking the bottles out of the machine. A
pipette or slender-spouted vessel may be used to add the water. Whirl
the bottles two minutes, then add more boiling water to bring the fat
column into the graduated part of the neck of the bottle. Then whirl one
minute. The test should be read at once or the bottles kept at a
temperature of 130° to 140° F. until ready to read.
+312. Reading the test.+--To read the test, subtract the reading at the
bottom of the fat column from that at the highest point. The curved
meniscus which always forms at the top of the fat column should be
included in the reading. Duplicate samples should not vary more than O.2
of 1 per cent. Standard Babcock test bottles and pipettes should always
be used. In some states the agricultural experiment stations examine all
glassware and mark it to make certain that it conforms to the
requirements of the state law. In New York, glassware found to be
correct is branded "S. B.," which means State Brand. In some states a
person must have a license to test milk or cream, when it is paid for on
the fat test. Such a person must pass an examination to show that he
understands the test before a license, will be granted. The license may
be revoked if the work is not honestly performed.
+313. Testing whey for fat.+--Because of the small amount of fat in
whey, it is difficult to obtain a representative sample. The best way,
if the entire amount cannot be placed in a vat and stirred, is to catch
a little of the whey at intervals as it is being drawn from the vat. The
sample to be tested is measured with the pipette the same as the milk
and placed in the skimmed-milk test bottle. The same acid is used to
test whey as to test milk but because there are not so many solids to
destroy, not so much is used. If as much acid is used with whey as with
milk, it will burn the fat and so interfere with the reading of the
test. Just enough acid is added to destroy the milk substances except
the fat, or enough to turn the contents of the test bottle dark brown.
This usually requires filling the acid measure one-quarter of an inch
under the graduation. The remainder of the test is the same as for whole
milk.
+314. Testing cheese for fat.+--The sample of cheese to test for fat is
obtained by removing the sample with a cheese-trier. This sample is
called a "plug." Different plugs from the same cheese will test various
percentages of fat so that it is difficult to secure a representative
sample. The usual practice is to take three plugs, one near the center,
another near the outside and the third between the first two. The plugs
should be put into glass-stoppered bottles to prevent the evaporation of
moisture. These plugs are then chopped up very fine. It is of course
impossible to measure the cheese as with milk and whey, but it is
weighed (Fig. 70). If the cheese is soft it can be stirred with a
spatula until well mixed. A soft cheese usually sticks to the neck of
the test bottle. After being weighed, it can be dissolved in a little
sodium hydroxide and poured into the bottle. Different amounts may be
used, commonly 4½ or 6 grams, but 6 grams is to be preferred. This is
placed in the Babcock cream bottle since there will usually be more fat
than can be read in a milk bottle. After the material has been placed in
the test bottle, about two-thirds of an acid-measure of warm water is
added to assist in dissolving the cheese.
[Illustration: FIG. 70.--Apparatus necessary to test cheese for fat.]
The acid is added the same as with the milk. If all the cheese particles
are not destroyed, and therefore do not disappear, a little more acid
will complete the solution. Centrifuging is performed as with the milk.
+315. Reading the test.+--In a cream-test bottle the neck is so much
wider that there is a much larger meniscus. In order to obtain an
accurate result, the meniscus should be removed. This is done by
carefully adding a substance called glymol, which is a mineral oil
colored red. Usually about one-quarter of an inch of glymol is added to
the fat column. This should not mix with the fat. The bottles should be
placed in a hot water bath 135° to 140° F. for four minutes before
reading. The temperature at reading should be 135° to 140° F. The
reading is then taken from the bottom of the fat column to the line
between this and the glymol. The bottle is graduated for 18 grams of
material, but as only a part of 18 grams of cheese was used for the
test, the reading should be multiplied by the part of 18 grams used. For
example, suppose 6 grams of cheese were used and the test read 12 per
cent fat. Since 6 is one third of 18, the actual percentage of fat is 3
times 12, or 36 per cent.
+316. The Hart[134] casein test+ was devised to determine the percentage
of casein in milk. A special test bottle and centrifuge are necessary.
The method of making the test is as follows: Place 2 c.c. of chloroform
in the casein test tube, add 20 c.c. of a 0.25 of 1 per cent solution of
acetic acid at a temperature of 65° to 75° F. This solution of acetic
acid is made by diluting 10 c.c. of glacial acetic acid with 100 c.c. of
water, then dilute 25 c.c. of this solution to 1000 c.c. with water; 5
c.c. of milk at a temperature of 65° to 75° F. is then run into the
bottle. The bottle is then covered with the thumb and inverted and the
mixture shaken vigorously for exactly twenty seconds. It is then
centrifuged within twenty minutes at a speed of 2000 revolutions a
minute. The bottle should stand ten minutes before reading the
percentage of casein. There are other tests for casein but they are very
complicated.
+317. Solids in the milk.+--Because not only the fat but all the solids
are utilized in cheese-making, it is important to know the amount of the
solids in the milk. This is ascertained by determining the specific
gravity of the milk and knowing the fat-content; the solids not fat can
then be calculated.
+318. The lactometer.+--The specific gravity of liquids is measured by
an instrument called a hydrometer. Its use is based on the fact that
when a solid body floats in a liquid, it displaces a volume of liquid
equal in weight to its own. Hydrometers are in many cases so made that
the specific gravity can be read at the point where the scale is even
with the upper surface of the liquid. A hydrometer that is especially
adapted to milk is called a lactometer. There are two lactometers in
common use, the Quevenne and the Board of Health.
[Illustration: FIG. 71.--A Quevenne lactometer.]
_The Quevenne lactometer._--This is a long slender hollow piece of glass
weighted at the bottom to make it float in the milk in an upright
position (Fig. 71). The upper end is slender and contains the scale.
This scale is graduated from 15 at the top to 40 at the bottom. Each
reading on the scale corresponds to the point marked specific gravity on
a hydrometer, except that the figures are not complete. For example, 15
on the Quevenne scale means a specific gravity of 1.015; a reading of
30 on the Quevenne scale means a specific gravity of 1.030, and so on.
The Quevenne lactometer is graduated to give correct results at a
temperature of 60° F. The milk should be at this temperature. If the
temperature is below or above this, a correction must be made to the
reading. The temperature should not be more than 10 degrees above or
below 60° F. The correction for each degree in variation of temperature
can be made by adding 0.1 or subtracting 0.1 from the lactometer
reading, as the case may be. If the temperature is above 60° F., the
correction is added to the lactometer and if it is below 60° F., the
correction is subtracted from the lactometer reading. The reading should
be taken when the lactometer is floating free in the milk. The scale is
read exactly at the surface of the milk. The better lactometers have a
thermometer with the scale just above or opposite the lactometer scale.
[Illustration: FIG. 72.--A Board of Health lactometer.]
_The Board of Health lactometer._--This is very similar to the Quevenne
lactometer except that the scale is graduated from 0 to 120 (Fig. 72).
The point on the scale of the lactometer that floats at the surface in
water is represented by 0, and 100 represents the specific gravity of
1.029. On the Board of Health lactometer, the 100 degrees or divisions
from 0 to 100 equal 29 divisions on the Quevenne. Therefore, one
division on the Board of Health equals 0.29 of a division on the
Quevenne. To convert Board of Health reading to Quevenne, multiply by
0.29 and to convert Quevenne to Board of Health, divide by 0.29. The
correction for temperatures above or below 60° F. is made the same as
with the Quevenne, except 0.3 is added or subtracted from the reading
instead of 0.1 as with the Quevenne.
+319. Calculating the solids not fat in the milk.+--When the lactometer
reading and fat-content of the milk are known, there are several
formulas for calculating the solids not fat. In the following formulas,
L equals Quevenne lactometer reading at 60° F., and F equals the
percentage of fat in the milk:
L + 0.7 F
--------- = S.N.F
3.8
L + F
----- = S.N.F.
4
L
- + 0.2 F + 0.14 = S.N.F.
4
+320. Testing cheese for moisture.+[135]--There are two methods of
testing cheese for moisture. The following is a simple test devised by
H. C. Troy:
The ordinary butter moisture test, in which a metal cup is heated over a
flame, cannot be used for determining the percentage of water in cheese
because the high temperature developed in operating that test drives
from he cheese other substances with the water. Also, particles are lost
by spattering when the cheese is heated with any degree of rapidity in
the shallow butter-moisture cups. To overcome these difficulties, the
new method here described has been developed for the purpose of
determining the percentage of moisture in cheese. The apparatus consists
of:
1 double-walled copper drying cup
1 centigrade thermometer registering to 200°
1 alcohol lamp
1 tripod
1 special flask
1 scales sensitive to 0.01 gram
1 set of weights, 0.01 to 100 grams
The body of the copper drying cup may be made in two parts. One of the
parts is a jacket that forms the outer wall of the apparatus. It has a
flat bottom 4½ inches in diameter, and the perpendicular wall is
4½ inches in height. The inner part of the cup must have a flat
bottom 2¾ inches in diameter and a side wall 3¾ inches high. A
flange attached to the upper rim of the inner part extends out at right
angles to the cup wall and forms a cover for the space between the walls
when the two parts are put together. The flange is bent down around its
outer edge to make it fit snugly over the upper rim of the outer jacket.
It thus holds the inner cup securely in place, leaving a space about ¾
inch wide for oil between the walls and bottoms, and permits the
apparatus to be taken apart readily. A circular opening about ½ inch
in diameter is made through the flange to permit the insertion of a
thermometer for taking the temperature of the oil or the melted fat
which is used in the space between the walls. Lard or tallow serves best
for use in this space; a readily inflammable oil should not be employed.
The thermometer may be permanently held in place by passing it snugly
through a hole bored in a cork, the cork being then fitted into the
hole through the flange. A flat metal cover is placed on the cup when
making a test. This cover has a hole through the center just large
enough to permit the neck of the drying flask to extend up through it.
The cover assists in keeping the body of the flask at a constant
temperature by preventing the entrance of cold air currents. The
thermometer should register changes in temperature between zero and 200°
C. The alcohol lamp should yield a flame about ¼ inch in diameter and
¾ inch high. The tripod should be about 6 inches high and of proper
diameter at the top to support the oil bath.
An ordinary flat-bottom glass Erlenmeyer flask, of such a diameter as to
fit neatly into the oil-bath cup, may be used to hold the cheese during
the drying operation; but a special glass flask serves better. It is
made with a flat bottom 2½ inches in diameter, which will fit into
the cup of the drying apparatus. The side walls of this flask should be
perpendicular for about 1 inch, when they should begin to slope in
toward the base of the neck, which should be located about 2 inches
above the bottom. The neck of the flask should be 1 inch in diameter,
with perpendicular walls, and its length should give the flask a total
height of 4¾ inches. When the apparatus (Fig. 73) is put together for
the first time, the melted fat or oil may be placed in the outer jacket
and the inner cup may then be fitted into position, or the parts may be
put together first and the oil then poured into the space between the
cup walls through the opening where the thermometer is to be placed. The
oil should fill the space to within an inch of the top. The cork
through which the thermometer has been passed is then fitted into the
opening. The thermometer bulb should be placed in the oil about half an
inch above the bottom of the outer jacket. The apparatus is then placed
on the tripod over the alcohol lamp. A flame ½ inch in diameter and
¾ inch high will give sufficient heat to hold the bath at the proper
temperature. The temperature may be regulated by raising or lowering the
lamp or by changing the size of the flame by adjusting the wick.
Hundreds of tests may be run without taking the apparatus apart or
changing the oil. The copper drying cup can be made by any tinsmith. The
other parts may be ordered through any dairy or chemical supply company.
[Illustration: FIG. 73.--Apparatus necessary to test cheese for
moisture.]
In operating the test, the alcohol lamp is first lighted, so that the
oil bath may be warming while the test sample is under preparation. A
representative sample of the cheese, which may be taken with a
cheese-trier and held in a glass-stoppered sample jar, is then cut into
particles about the size of kernels of wheat without removing it from
the jar. This may be accomplished with an ordinary table knife that has
had the end squared and sharpened. The clean dry flask is then
accurately balanced on the scales and a 5-gram weight is placed in the
opposite scale pan. Particles of cheese from the prepared sample are put
into the flask until the scales comes to an exact balance. Great care
should be taken to avoid loss of moisture from the cheese in the
preparation of the sample.
With the thermometer in the oil bath registering between 140° and 145°
C. (or between 284° and 293° F.), the flask is placed in the cup of the
oil bath and the flat disk-shaped cover is adjusted over the apparatus.
The flask should remain in the bath for fifty minutes, the temperature
being kept between 140° and 145° C. all the time. The flask is then
removed, covered and allowed to cool to room temperature in a dry place.
It is then weighed, and the quotient obtained by dividing the loss in
weight by the original weight, multiplied by 100, gives the percentage
of water in the cheese. The following shows the method of computation:
Problem: Five grams of cheese was heated until the water contained in it
was evaporated. The remaining substance weighed 3.15 grams. What
percentage of water did the cheese contain?
Answer: 5.00 - 3.15 = 1.85
1.85 ÷ 5 = 0.37
0.37 × 100 = 37 (percentage of water in cheese)
A butter-moisture scales with an extra 5-gram weight may be used for
weighing out the 5 grams of cheese. If the scales indicates the amount
of moisture in 10 grams of butter by percentage graduations on its beam
or by percentage weights, then it will be necessary to multiply by 2 the
percentage indicated by such scales or percentage weights when only 5
grams of cheese is used.
The moisture may be determined by weighing out a small sample of cheese
and drying it in an oven and calling the loss moisture. Many such ovens
have been devised.
New York and Wisconsin have laws limiting the amount of water which may
be incorporated in Cheddar cheese. New York places the limit at 39 per
cent and Wisconsin at 40 per cent. If the moisture-content is above
this, the cheese must be branded adulterated.
CHAPTER XX
_MARKETING_
Marketing is related to cheese in two ways: First, the purchase of the
raw material, the milk; and secondly the sale of the finished product,
the cheese.
+321. Buying milk.+--The method of paying for the milk differs in the
various cheese sections and factories. At some factories a stated price
is paid for the milk or the fat. This is usually in terms of 100 pounds
of milk or for each pound of fat. This is the practice with concerns
possessing large capital. Other factories make the milk into cheese and
after each sale, the expenses necessary for operating the factory are
deducted and the remainder of the money divided among the patrons. This
money is divided either on the basis of the number of pounds of milk or
of fat delivered. The question arises as to which is the better method
to buy milk for cheese-making, or the fairest way to divide the money
received from a sale of cheese.
+322. Cheese yield basis of buying milk.+--Let us suppose that at a
cheese factory there were five patrons: (A) delivered 100 pounds of milk
testing 3 per cent fat; (B) 100 pounds of milk testing 3.5 per cent fat;
(C) 100 pounds of milk testing 4.0 per cent fat; (D) 100 pounds of milk
testing 4.5 per cent fat; and (E) 100 pounds of milk testing 5.0 per
cent fat. Table XXVI shows the actual number of pounds of cheese
containing 37 per cent moisture which 100 pounds of milk containing
different percentages of fat will produce. The cheese sold net for 20
cents a pound.
TABLE XXVI
SHOWING PAYMENTS FOR MILK BASED ON THE ACTUAL YIELD
OF CHEESE
=====================================================================
PATRON | POUNDS | PER CENT | YIELD OF CHEESE | PRICE A | AMOUNT
| OF MILK | OF FAT IN | CONTAINING | POUND | DUE EACH
| DELIVERED | MILK | 37% MOISTURE | | PATRON
-------+-----------+-----------+-----------------+---------+---------
A | 100 | 3.0 | 8.30 | $.20 | $1.66
B | 100 | 3.5 | 9.45 | .20 | 1.89
C | 100 | 4.0 | 10.60 | .20 | 2.12
D | 100 | 4.5 | 11.74 | .20 | 2.348
E | 100 | 5.0 | 12.90 | .20 | 2.58
-------+-----------+-----------+-----------------+---------+---------
Total | 500 | 20 | 52.99 | .20 | 10.598
=====================================================================
This table shows the amount of money each patron should receive if the
money were divided on the basis of the actual yield of cheese.
+323. Fat basis for payment of milk.+--Let us suppose that the same five
patrons delivered the same quantity of milk testing the same percentages
of fat and that the cheese sold for the same price. A total of 20 pounds
of fat was delivered and the cheese sold for $10.598; by dividing this
amount by the pounds of fat delivered, the price or value of one pound
of fat is found to be $.5299. Multiplying the pounds of fat each patron
delivered by the price a pound would give the amount of money due each
patron.
TABLE XXVII
SHOWING PAYMENTS FOR MILK BASED ON FAT-CONTENT OF
MILK
===================================================================
| POUNDS | PER CENT | POUNDS OF | VALUE OF |
PATRON | OF MILK | OF FAT IN | FAT | POUND OF | AMOUNT DUE
| DELIVERED | MILK | DELIVERED | FAT | EACH PATRON
-------+-----------+-----------+-----------+----------+------------
A | 100 | 3.0 | 3.0 | $.5299 | $1.58
B | 100 | 3.5 | 3.5 | .5299 | 1.85
C | 100 | 4.0 | 4.0 | .5299 | 2.12
D | 100 | 4.5 | 4.5 | .5299 | 2.38
E | 100 | 5.0 | 5.0 | .5299 | 2.65
===================================================================
+324. Weight basis or pooling method for payment of milk.+--By this
system, each patron would receive an equal price for 100 pounds of milk.
If the same supposition is taken as before, there would be 500 pounds of
milk delivered and the cheese sold for $10.59; each 100 pounds of milk
would be worth $2.12. As each patron delivered an equal weight of milk,
each would receive an equal amount of money, or $2.12.
+325. Fat-plus-two method for payment of milk.+--Some workers have
thought that by adding two to the fat test, the division of money would
be more nearly the true cheese-producing value of the milk. The amount
due each patron is figured as in the fat basis, except that two is added
to the fat test and this is used as the basis of division. If the same
suppositions were used as before, each patron would receive the amount
shown in Table XXVIII.
+326. Comparison of methods.+--The best way to judge the different
methods of paying for milk is to compare them with the true value based
on the actual cheese yield as shown in Table XXIX.
TABLE XXVIII
SHOWING PAYMENTS FOR MILK BY FAT-PLUS-TWO METHODS
===========================================================================
PATRON | POUNDS | PER CENT | FAT PLUS | POUNDS | VALUE OF | AMOUNT
| OF MILK | OF FAT IN | TWO | OF FAT | POUND OF | DUE EACH
| DELIVERED | MILK | | DELIVERED | FAT | PATRON
-------+-----------+-----------+----------+-----------+----------+---------
A | 100 | 3.0 | 5.0 | 5.0 | $.353 | $1.76
B | 100 | 3.5 | 5.5 | 5.5 | .353 | 1.94
C | 100 | 4.0 | 6.0 | 6.0 | .353 | 2.12
D | 100 | 4.5 | 6.5 | 6.5 | .353 | 2.29
E | 100 | 5.0 | 7.0 | 7.0 | .353 | 2.47
===========================================================================
TABLE XXIX
SHOWING THE COMPARISON OF THE DIFFERENT METHODS
OF PAYING FOR MILK AT CHEESE FACTORIES
================================================================
| | ERROR IN PAYMENT PER 100 POUNDS OF MILK BY
PATRON | PERCENTAGE +----------------+-----------+--------------
| OF FAT IN | POOLING SYSTEM | FAT BASIS | FAT-PLUS-TWO
| MILK | | | METHOD
-------+------------+----------------+-----------+--------------
A | 3.0 | +$0.46 | -$0.08 | +$0.10
B | 3.5 | +0.23 | -0.04 | +0.05
C | 4.0 | 0.00 | 0.00 | 0.00
D | 4.5 | -0.23 | +0.04 | -0.05
E | 5.0 | -0.46 | +0.08 | -0.10
================================================================
A careful study of the above table shows that the pooling system is in
favor of the dairy-man with the poor milk, and that the fat basis favors
the dairy-man with the rich milk. This is due, of course, to the fact
that the casein does not increase in the milk quite in proportion to the
fat. With the pooling system or fat basis of payment, no account is
taken of the casein; but the fat-plus-two system is an attempt to
recognize the casein, but considers the percentage of casein in all milk
to be the same. This method is in favor of the dairy-man with milk low
in fat, but not to the extent of the pooling system. The latter system
considers the cheese-producing power of all milk to be the same. It
favors the dairy-man with low-testing milk. The fat basis for payment
recognizes only the fat and is an advantage to the dairy-man with the
high-testing milk but not to the extent that the pooling system is in
favor of the low-testing milk. The fat-plus-two method recognizes 2 per
cent of casein in the milk. This favors the dairy-men with low-testing
milk. Other methods[136] of paying for milk have been devised. Because
the actual yield of cheese from the milk of different herds cannot be
easily determined at the cheese factory, this method of payment cannot
be employed. In localities in which all the dairy-men have the same
breed of cattle and there is not a wide variation in the fat percentage,
the fat basis is usually found to be the most satisfactory way to pay
for the milk.
+327. Laws governing the production and sale of milk.+--Many states have
laws regulating the sanitary conditions under which the milk may be
produced. These laws relate principally to the condition of the stables,
the health of the cow, the food given the cow, and the care of the milk.
The following law[137] of Wisconsin is a good example:
"Adulterated milk, what constitutes. Section 4607a. In all
prosecutions under the preceding section, or any other
section of these statutes, or laws amendatory thereof or
supplementary thereto, relating to the sale of adulterated
milk or adulterated cream, the term adulterated milk shall
mean: milk containing less than three per centum of milk
fat, or milk containing less than eight and one-half per
centum of milk solids not fat, or milk drawn from cows
within eight days before or four days after parturition,
or milk from which any part of the cream has been
removed, or milk which has been diluted with water or any
other fluid, or milk to which has been added or into which
has been introduced any coloring matter or chemical or
preservative or deleterious or filthy substance or any
foreign substance whatsoever, or milk drawn from cows kept
in a filthy or unhealthy condition, or milk drawn from any
sick or diseased cow or cow having ulcers or other running
sores, or milk drawn from cows fed unwholesome food, or
milk in any stage of putrefaction, or milk contaminated by
being kept in stables containing cattle or other animals.
The term adulterated cream shall mean cream containing
less than eighteen per centum of milk fat, or cream taken
from milk drawn from cows within eight days before or four
days after parturition, or cream from milk to which has
been added or introduced any coloring matter or chemical
or preservative or deleterious or filthy substance or any
foreign substance whatsoever, or cream from milk drawn
from cows kept in a filthy or unhealthy condition, or
cream from milk drawn from any sick or diseased cow or cow
having ulcers or other running sores, or cream from milk
drawn from cows fed unwholesome food, or cream
contaminated by being kept in stables containing cattle or
other animals, or cream to which has been added or into
which has been introduced any coloring matter or chemical
or preservative or deleterious or filthy substance or any
foreign substance whatsoever, or cream in any stage of
putrefaction, provided, that nothing in this act shall be
construed to prohibit the sale of pasteurized milk or
cream to which viscogen or sucrate of lime has been added
solely for the purpose of restoring the viscosity, if the
same be distinctly labeled in such manner as to advise the
purchaser of its true character; and providing that
nothing in this act shall be construed as prohibiting the
sale of milk commonly known as 'skimmed milk,' when the
same is sold as and for 'skimmed milk.' Milk drawn from
cows within eight days before or four days after
parturition, or milk to which has been added or into which
has been introduced any coloring matter or chemical or
preservative or deleterious or filthy substance, or milk
drawn from cows kept in a filthy or unclean condition, or
milk drawn from any sick or diseased cow or cow having
ulcers or other running sores, or milk drawn from cows
fed unwholesome food, or milk contaminated by being kept
in stables containing cattle or other animals and cream
from any such milk, or cream in any stage of putrefaction
are hereby declared to be unclean and unsanitary milk or
unclean and unsanitary cream, as the case may be."
Most states have laws which determine the legal standard of milk. Any
one selling milk which does not meet this standard is liable to be
fined. The laws of most states prohibit the taking of anything from the
milk or the adding of anything to it. This prohibits the skimming and
watering. Skimmed-milk must be sold as such.
+328. Marketing of cheese.+--There are many different methods[138] of
selling cheese. Each is adapted to certain conditions and each has its
advantages and disadvantages. In cheese sections, the customary method
of selling is on the board of trade, which is the meeting of the
cheese-buyers and factory salesmen. They meet at a given place at a
certain day and hour each week. Every board has its officers. There are
different ways in which a board of trade may be operated. In some cases
there is a large blackboard divided into columns. In the first column,
the salesman writes the name of the factory and the number and kind of
cheese offered for sale. At the top of the other columns are the names
of the different cheese-buyers. The president usually opens the sale at
a stated time and asks that all cheese be placed on the blackboard. When
this is done he states that they are ready to receive bids on the
cheese. The buyers then write the price a pound they wish to pay
opposite each lot of cheese and in the column headed by their names.
After all the bids have been received and placed on the board, the
presiding officer states that a certain length of time, usually fifteen
minutes, will be given the salesman to withdraw his cheese if he does
not think a high enough price has been offered; this is indicated by the
salesman stepping to the blackboard and erasing the factory name and
number of boxes. At the close of the stated time, the presiding officer
declares the cheese offered on the board sold to the highest bidder. The
purchaser then gives the salesman directions for shipping.
Sometimes a board of trade has a committee of one member elected by the
factory salesmen and one elected by the cheese-buyers. These two members
elect a third and these three constitute the price committee. This
committee meets each week and determines what the price shall be. This
is known as the ruling. The factory salesmen and cheese-buyers then try
to make private sales. By this method no one, except the persons
concerned, knows exactly what price is paid for the cheese. Usually, a
price above the ruling is paid.
At Quebec, Canada, there is a cheese-selling organization with
government assistance. On paying a certain fee, any cheese factory may
join. All the factories belonging to the organization ship their cheese
to a central cold storage where the cheeses are examined and graded by a
government inspector. A cheese from each vat is tried. These cheeses are
separated into white and colored lots, then graded according to quality.
When the total number of cheeses in each lot is known, the lots are sold
at auction. The purchaser must accept the cheese as graded. The better
grades of cheese bring about the same price as on the market, but the
advantage lies in the selling of the lower grades. Ordinarily, the
purchaser takes advantage of the salesman when the cheeses are
undergrade. The success of this plan depends on the accuracy of the
person grading the cheese. This method seems to be growing in
popularity, because the cheese-buyer can purchase large amounts of
cheese at one time and be sure of the quality. A small fee, about
one-twelfth of a cent a pound, is charged for handling the cheese.
Similar organizations are in operation in Wisconsin. The boards of trade
and selling organizations deal almost entirely in Cheddar cheese.
+329. Mercantile exchanges.+--In the larger cities are exchanges where
cheese is bought and sold by jobbers. This cheese is mostly Cheddar. The
prices paid these jobbers tend to fix the daily price of cheese. These
prices are published daily, for example, in New York Price Current. Some
factories ship their cheese directly to these jobbers. The following are
the cheese rules of the New York Mercantile Exchange adopted May 4,
1915:
CHEESE RULES OF THE NEW YORK MERCANTILE EXCHANGE
Rule 1. At the first regular meeting of the Executive
Committee in each year, the President shall appoint,
subject to the approval of the Executive Committee, a
Cheese Committee to consist of seven members of the
Exchange, who are known as members of the cheese trade, to
hold office until their successors are appointed. It shall
be the duty of the Cheese Committee to formulate such
rules and regulations as may be necessary for the
government of transactions between members of the
Exchange, and to revise the same as circumstances may
require. Such rules and revisions shall be subject to the
approval of the Executive Committee.
Rule 2. All transactions in cheese between members of the
Exchange shall be governed by the following rules, but
nothing therein shall be construed as interfering, in any
way, with the rights of members to make such special
contracts or conditions as they may desire.
Rule 3. If a sale is made from dock, or platform, or to
arrive, the buyer shall assume the same relations toward
the transportation line by which the cheese arrives, as
the seller previously held as regards its removal from the
place of delivery within the time granted by such lines
for that purpose. Transactions between members of this
Exchange shall be governed as follows: Any member
negotiating for any lot of cheese belonging to another
member, the price having been agreed upon, shall examine
such lot of cheese within twenty-four (24) hours after
such negotiation takes place. Failure to examine within
said time releases the seller from any obligations to make
delivery thereafter, if he so wishes.
Rule 4. In the absence of special agreement, all cheese
purchased "in store" shall be understood as being ready
and designed for immediate delivery, but the buyer shall
have twenty-four hours in which to have the cheese
inspected, and weight tested, and shall not be liable for
the storage and insurance, if removed within two days.
Rule 5. When cheese are sold to arrive, or from depot or
dock, the cheese must be accepted or rejected within six
business hours after notice of actual arrival to buyer.
Business hours shall be understood to be from 10 A.M. to 4
P.M. If buyer rejects the same, he shall state the reasons
for rejection. Should the rejection be considered unfair,
the seller shall at once notify the buyer that he declines
to accept such rejection; and he may call for a Committee,
which shall be composed of three members of the cheese
trade; the seller choosing one, the buyer one, and the
third selected from the cheese trade by these two, or,
they failing to agree, the third shall be appointed by the
Chairman of the Committee on Cheese. The Examining
Committee shall at once inspect the lot of cheese in
dispute, sampling not less than five (5) per cent of each
mark or factory, and they shall immediately give their
decision in writing to both parties. Either party failing
to abide by the decision of the Committee may be summoned
by the other party before the Complaint Committee under
Section 24 of the By-laws. The fees for each examination
shall be six ($6) dollars, to be paid by the party
adjudged to be in fault.
Rule 6. The weight of all cheese shall be tested by a
regularly appointed official weigher, and his certificates
shall accompany the document conveying the title of the
property. Said official weigher to be appointed by the
Committee on Cheese, subject to the approval of the
Executive Committee.
Rule 7. The weigher's fee shall be twenty-five (25) cents
per factory except where the owner requires more than ten
(10) boxes be tested in which case the fee shall be fifty
(50) cents, which shall be paid by the seller.
Rule 8. Unless otherwise agreed upon in testing the weight
of cheese, not less than five (5) boxes or more than ten
(10) per cent of the whole lot shall be a test, and said
test shall be considered good for three (3) business days,
including day test is made.
Rule 9. In testing weights, all over and short weights
shall be taken into the average on each particular
factory. Single Daisies shall be tested on half pounds,
Double Daisies and all other sizes on even pounds.
Rule 10. Where a lot of cheese is found to test irregular
in weights, either the buyer or seller may require the
entire lot to be reweighed. The charge for same shall be
three (3) cents per box.
Rule 11. Boxes of cheese which may be found largely at
variance from original weights shall not enter into the
average, but their weight shall be separately ascertained
and certified to by the weigher.
Rule 12. Where sales are made, and the buyer finds damaged
or sour cheese in excess of fifteen (15) per cent it shall
be optional with him to refuse or receive the remainder of
the lot purchased. But, in the event of his accepting the
remainder of the lot, the sour or damaged cheese shall
revert to the seller.
Rule 13. The Committee on Cheese shall appoint subject to
the approval of the Executive Committee, a Cheese
Inspector and also a Deputy Inspector, whose duties shall
be, when called upon by members of the Exchange, to
inspect the quality and condition of such lots of cheese
as may be required and to render a certificate of such
inspection. Where the cheese in the lots are reasonably
uniform in quality, the examination of 10 per cent of the
lot shall be considered sufficient, but this shall not
prevent the Inspector examining a larger percentage of the
lot, when he deems it necessary. The fee for inspection
shall be fifty (50) cents for lots consisting of fifty
(50) boxes or less. Lots exceeding fifty (50) boxes shall
be one cent per box, which shall be collected from the
member ordering the inspection.
Rule 14. The Cheese Inspector's certificate shall be made
to read as follows:
NEW YORK MERCANTILE EXCHANGE
_Cheese Inspector's Certificate_
Inspection No.__________
This is to certify that I have this day inspected for M___________
the following cheese, now located at_____________________
Factory and identification marks_________________________
Quantity in lot__________________________________________boxes
Quantity inspected_______________________________________boxes
and find as follows:
Flavor_______________________________________________________________
Body and Texture_____________________________________________________
Color________________________________________________________________
Condition____________________________________________________________
Boxes________________________________________________________________
Grade________________________________________________________________
Inspection charges________________
_____________________________________Inspector_
The certificate to have a blank margin of three inches at
the bottom, for the purpose of inserting specifications of
Institutions, also for cheese sold under the Call, so that
the Inspector may certify that cheese inspected fill the
requirements as specified and the Inspector shall brand
one impression on both boxes and cheese.
NEW YORK MERCANTILE EXCHANGE
OFFICIAL INSPECTION
Number_______________ Date___________________________
____________________________Inspector_
Rule 16. The Weigher's Certificate shall be made to read
as follows:
This is to certify that the following is the actual test of ______
boxes, out of shipment of ______ boxes
Factory Mark___________________________________________
Marked Weights_________________________________________
Actual Weights_________________________________________
Loss___________________________________________________
Average loss_______________lbs. on________________boxes
New York_____________________________19______
______________________ _Weigher_
and the Cheese Rules numbered 6 to 11 inclusive be printed
on the back thereof.
Rule 17. Members offering cheese for sale under the Call
shall describe each lot, as to number of boxes, color,
texture (open or close made), body, flavor, size, and how
boxed, section where made, whether whole milks or skims
and the average weight of each lot. Cheese sold under the
Call to be accepted, or rejected, as a good delivery, or
otherwise, based on the description given at the sale.
Rule 18. When cheese are sold under the Call, unless
otherwise stated, they shall be ready for immediate
shipment.
Rule 19. All cheese offered under the Call, with
Inspector's Certificate attached, shall be accompanied by
such Certificate and be accepted by the buyer
unconditionally, provided the cheese are branded according
to Rule 13.
Rule 20. When cheese are offered under the Call, without
Inspector's Certificate, should the buyer not consider the
cheese a good delivery, according to description by
seller, he may notify the seller, and if the seller is
unwilling to make another delivery, the buyer may call
upon the Inspector to decide whether or not the delivery
shall stand. If the Inspector decides it is a good
delivery, the buyer shall accept the cheese. If the
Inspector decides it is not a good delivery, then the
seller shall have twenty-four (24) hours in which to make
a good delivery. But if the seller, after twenty-four (24)
hours, fails to make a good delivery, then the buyer shall
notify the Superintendent of the Exchange, who shall
collect a penalty of three per cent of the amount of the
transaction, the Exchange retaining twenty-five per cent
of this sum, and seventy-five per cent shall be paid to
the buyer.
Rule 21. Spot sales under the Call shall be for spot cash
unless otherwise agreed.
Rule 22. All failures in meeting contracts shall be
reported to the Superintendent of the Exchange, and
announced at next regular session of the Exchange.
+330. Marketing perishable varieties.+--Soft cheeses, such as Cream,
Neufchâtel, Cottage, are usually sold to jobbers or directly to retail
stores. They have a very short commercial life, hence cannot be held
long before delivery to the consumer. From the jobber, cheese usually
goes to the wholesale grocer and then to the retail dealer and finally
the consumer. Most jobbers have cold storages so that they can hold
cheese without injury to quality. (See Fig. 74.) The kind of cheese
marketed in any locality depends on the tastes of the residents. For
example, the South usually desires a highly colored product, thinking
this color indicates more fat; in the Cheddar group New England demands
a soft pasty quick-curing cheese, thinking that softness is a sign of
more fat and richness; England wants a rather dry, well-cured, highly
flavored cheese. Canadian Cheddar cheese has been standardized as far
as possible to appeal to the English market. A long ripening period
keeps capital tied up through the further time required for delivery.
This has led to the sale of much of the cheese almost or entirely
unripe. So much of the product has reached the consumer without
characteristic varietal flavor that large numbers have acquired the
habit of purchasing and even preferring cheese only partly ripe.
[Illustration: FIG. 74.--A cheese cold storage room.]
The time during which cheese should be held at the factory depends on
the variety. Some are shipped as soon as made, including those cheeses
with sour-milk flavor only. Others have to be cured in the factory from
six to eight weeks. Cheeses in paper or tin-foil should be neatly
wrapped and carefully put in the boxes. The box of cheese should be
neat, clean and attractive. Cheeses not wrapped should have a firm rind
to hold them in shape. The boxes should be clean and the weight of
cheese neatly and plainly marked. In the case of Cheddar cheese, it may
be paraffined at the factory, but if not, this is usually done at the
cold storage of the jobber. The cheeses usually have some time to cure
or ripen while being handled by the various dealers.
+331. Distribution of price.+--The final selling price of cheese is a
composite of all the changes that have gone before; or conversely, the
farmer, the maker, the carrier and the distributors (wholesale, jobbing
and retail dealers) must all be paid from the final price of the
product. A study of this problem in Wisconsin has been made by Hibbard,
and Hobson.[139] The general facts as determined for Wisconsin have
fairly wide application to the manufacture and sale of cheese.
Economic success in handling cheese is dependent on proper provision for
the sale of the product. Where the output is small, a personal market
can be created and maintained. This eliminates all profits intervening
between the maker and the retailer. If the business reaches a volume
beyond the possibilities of direct sale to the retailer, some selling
organization is necessary. Where the number of producers is great and
the selling machinery is well organized, the cheese factory becomes a
producer of a commodity which is turned over to existing selling
agencies. This condition is well established for Cheddar, Swiss, Brick
and Limburger cheese. The soft cheeses other than Limburger have thus
far been handled principally by large companies, each of which has
developed an expensive selling organization. A study of the map (Fig.
65) shows how the cheese industry is localized in particular sections of
certain states. Individual factories have maintained themselves in
widely separated places. This localization is due to the geographical
conditions which make certain regions specially adapted to dairying,
modified by the proximity to markets for milk as milk. There are many
regions, however, well adapted to cheese production in which there is no
development of the industry at present. New developments are now taking
place in the mountain areas of the South, notably North Carolina and
adjacent states, and in several centers of the western mountain states.
Many other areas should develop the making of cheese in some form.
The actual costs of making and selling cheese were found by the
Wisconsin investigators to vary approximately as follows: (1) cost of
making, 1.2 to 1.75 cents; (2) storage, 1/8 cent a pound a month, or
3/8 to ½ cent for the season; (3) transportation to distant points,
$.20 to $2.50 for 100 pounds according to distance; (4) the local
dealer, about 1 cent a pound; (5) the wholesale dealer, 2 cents; (6) the
jobber or broker who occasionally intervenes, about 1/8 to ¼ cent; and
the retailer, 5.5 to 9 cents. The entire cost of selling at the time
this investigation was made represented about one-half of the retail
price of the cheese. The producer of milk received the other half of
that price.
+332. Standards.+--Legal standards in the United States are thus far
largely based on the specifications of American Cheddar. In so far as
they are applied to other products, they operate merely to prevent or
reduce the use of skimmed-milk. The analyses and limits proposed in the
discussion of varieties or groups in this book represent the range of
composition actually known to be associated with cheeses of typical
quality. Efforts are now being made to establish definitions and
standards of composition which will limit the use of cheese names to
products conforming to the requirements for such varieties. Practically
the only federal requirement thus far enforced in the United States is
that 50 per cent of the water-free substance of the cheese must be
milk-fat. Various states have local requirements but most of them
include the federal rule as to fat. New York and Wisconsin now restrict
the amount of water in Cheddar cheese to 40 per cent. Most states have
laws regulating the manufacture and sale of skimmed-milk cheese.
+333. Laws relating to cheese marketing.+--A cheese of foreign origin if
made in this country must be branded to show that it is not imported.
For example, Camembert made in America is labeled Domestic Camembert.
Some manufacturers call it Camembert type of cheese. The same applies to
other varieties of foreign cheese. If a variety is made under a
trade-marked name, this prevents any other manufacturer from using that
name. For example, a concern may make "Philadelphia" cream cheese; other
concerns may make cream cheese, but they must call it by some other
name.
The committee on definitions and standards for the Association of
Official Agricultural Chemists has now undertaken to define the proper
use of type names. This is intended to determine the proper limits of
composition of cheeses in each variety and such essentials of physical
identification as will insure the proper use of these names.
Certain states have laws which relate to the branding of the cheese to
denote quality. If the cheese is made from whole milk, a brand may be
applied to show this fact. This is usually called the state brand. If
made from skimmed-milk, the cheese must be branded to show this. The
following[140] illustrate the laws relating to the state brand and
skimmed-milk cheese:
Sec. 48. Manufacturer's brand of cheese. "Every
manufacturer of whole-milk cheese may put a brand or label
upon such cheese indicating 'whole-milk cheese' and the
date of the month and year when made; and no person shall
use such a brand or label upon any cheese made from milk
from which any of the cream has been taken. The
Commissioner of Agriculture shall procure and issue to the
cheese manufacturers of the state, on proper application
therefor, and under such regulations as to the custody and
use thereof as he may prescribe, a uniform stencil brand
or labels bearing a suitable device or motto, and the
words 'New York state whole-milk cheese.' Every such
brand or label shall be used upon the outside of the
cheese and shall bear a different number for each separate
factory. The commissioner shall keep a book, in which
shall be registered the name, location and number of each
manufactory using the brands or labels, and the name or
names of the persons at each manufactory authorized to use
the same. No such brand or labels shall be used upon any
other than whole-milk cheese or packages containing the
same. (As amended by chapter 207 of the Laws of 1910.)
Sec. 49. Use of false brand prohibited; branding of
skim-milk cheese regulated. No person shall offer, sell or
expose for sale, in any package, butter or cheese which is
falsely branded or labeled. No person shall sell, offer or
expose for sale cheese commonly known as Cheddar cheese
made from skimmed or partially skimmed milk unless the
same is branded to show that it is skim-milk cheese. All
such cheese so sold, offered or exposed for sale shall be
branded with the words 'skim-milk cheese,' or if such
cheese contains thirteen per centum of milk fat or over,
it may be branded 'medium skim-milk cheese,' or if it
contains eighteen per centum of milk fat or over, it may
be branded 'special skim-milk cheese.' Such branding shall
be upon the sides of both the cheese and the container.
The branding herein provided shall be in block letters at
least one-half an inch square. (As amended by chapter 456
of the Laws of 1913.)"
Filled cheeses are those from which the milk-fat has been removed and
other animal fats substituted. The laws of some states prohibit the
manufacture of this product. The federal law relating to filled cheese
permits its manufacture under license, taxes and government inspection.
The various states have laws regulating the length of time that the
cheese may be held in cold storage.
Another important law in some states requires the cheese-maker to have a
license. He must pass an examination to show that the principles and
practices of cheese-making are understood.
CHAPTER XXI
_CHEESE IN THE HOUSEHOLD_
Although cheese in some form is familiar to every household, it has been
widely regarded in America as an accessory, almost a condimental
substance rather than as a staple food worthy of comparison with meat or
eggs. Statistics of the annual production, importation and exportation
of cheese indicate that the total consumption in the United States is
about 300,000,000 pounds--perhaps three pounds per capita. The household
manufacture and consumption of cottage cheese would add a small amount
to these figures.
Cheese is used as a staple source of food values among many peoples of
Europe. Such use of cheese increases rather than decreases with the
density of the population. France with a small fraction of the land area
and one-half the population of the United States produces and consumes
about the same amount of cheese. In America, cheese-making has been
developed with the advance of settlement into unoccupied territories
only to be dropped as increasing population produced greater demands for
milk in other forms. If cheese had been accepted as a regular part of
the food supply in such communities, some form of cheese-making would
have survived the economic changes.
+334. Food value of cheese.+--A consideration of the nutritive
components of cheese shows it to be a rich source of fat, protein or
both, according to the variety under examination. It is low in
carbohydrates, and aside from salt (sodium chloride) compares favorably
with other substances in mineral constituents. The following discussion
with an amplified table is taken from Langworthy and Hunt:[141]
"In order, however, that the question of the use of cheese in the diet
may be adequately discussed, knowledge of its composition in comparison
with other foods is desirable, and there is an abundance of data
available on this subject, since the composition of cheese and other
foods has often been investigated at the Department of Agriculture, in
experiment station laboratories and in many other places where nutrition
problems are studied. An extended summary of analyses of cheese of
different sorts is included in an earlier publication of this
department.[142]
"Data regarding the composition of cheese and a few other common foods
are summarized in the following table.
"It will be seen from the table (Table XXX) that cheese has nearly twice
as much protein, weight for weight, as beef of average composition as
purchased and that its fuel value is more than twice as great. It
contains over 25 per cent more protein than the same weight of
porterhouse steak as purchased, and nearly twice as much fat.
"As shown by the figures in the following table, cheese contains 3.8 per
cent ash. Of this a considerable part may be salt added in
cheese-making. Like the milk from which it is made, cheese ash is
characterized chiefly by the presence of calcium (lime), magnesium,
phosphorus and iron, the average values as given in earlier bulletins of
the department[145] being 1.24 per cent calcium oxid, 0.049 per cent
magnesium oxid, 1.49 per cent phosphorus pentoxid, and 0.0015 per cent
iron."
TABLE XXX
AVERAGE COMPOSITION OF CHEESE AND SOME OTHER COMMON FOODS AS PURCHASED,
AND ALSO ON THE BASIS OF EDIBLE PORTION
====================================================================
| | | | | |
| | | | | |
FOOD MATERIALS | REFUSE | WATER | PROTEIN | FAT | CARBO |
| | | | | HYDRATES |
| | | | | |
----------------------+--------+-------+---------+------+----------+
| % | % | % | % | % |
Cheese, American | | | | | |
Cheddar[144] | -- | 34.2 | 25.2 | 33.7 | 2.4 |
| | | | | |
Beef of average | | | | | |
composition | | | | | |
as purchased | 18.6 | 50.5 | 15.2 | 15.5 | -- |
Edible portion | -- | 62.2 | 18.8 | 18.8 | -- |
| | | | | |
Porterhouse steak | | | | | |
as purchased | 12.7 | 52.4 | 19.1 | 17.9 | -- |
Edible portion | -- | 60.0 | 21.9 | 20.4 | -- |
| | | | | |
Loin steak, broiled, | | | | | |
edible portion | -- | 54.8 | 23.5 | 20.4 | -- |
| | | | | |
Dried beef | -- | 53.7 | 26.4 | 6.9 | -- |
| | | | | |
Eggs as purchased | 11.2 | 65.5 | 13.1 | 9.3 | -- |
Edible portion | -- | 73.7 | 13.4 | 10.5 | -- |
| | | | | |
Milk | -- | 87.0 | 3.3 | 4.0 | 5.0 |
| | | | | |
Bread | -- | 35.3 | 9.2 | 1.3 | 53.1 |
| | | | | |
Potatoes as purchased | 20.0 | 62.6 | 1.8 | .1 | 14.7 |
Edible portion | -- | 78.3 | 2.2 | .1 | 18.4 |
| | | | | |
Apples as purchased | 25.0 | 63.6 | .3 | .3 | 10.8 |
Edible portion | -- | 84.6 | .4 | .5 | 14.2 |
====================================================================
=====================================================
| | | FUEL
| | FUEL | VALUE
FOOD MATERIALS | ASH | VALUE | COMPARED
| | PER | TO
| | POUND | CHEESE[143]
----------------------+------+----------+------------
| % | Calories |
Cheese, American | | |
Cheddar[144] | 3.8 | 1,950 | 1.00
| | |
Beef of average | | |
composition | | |
as purchased | .7 | 935 | 0.48
Edible portion | .9 | 1,145 | 0.58
| | |
Porterhouse steak | | |
as purchased | .8 | 1,110 | 0.57
Edible portion | 1.0 | 1,270 | 0.65
| | |
Loin steak, broiled, | | |
edible portion | 1.2 | 1,300 | 0.66
| | |
Dried beef | 8.9 | 790 | 0.45
| | |
Eggs as purchased | .9 | 635 | 0.32
Edible portion | 1.0 | 720 | 0.37
| | |
Milk | .7 | 310 | 0.16
| | |
Bread | 1.1 | 1,215 | 0.62
| | |
Potatoes as purchased | .8 | 295 | 0.15
Edible portion | 1.0 | 385 | 0.20
| | |
Apples as purchased | .3 | 190 | 0.10
Edible portion | .3 | 290 | 0.15
=====================================================
It is clear from the calculations shown in the last column, that Cheddar
cheese takes first rank among the foods compared as to fuel value. The
estimate of food values in terms of calories may not completely express
the value of that food to a particular individual. It is generally
conceded that one great function of food is the production of energy and
this function is probably more closely determined by the number of
calories produced than in any other known way. Such calculation has
become an essential factor in the preparation of dietaries. The
calculation here given necessarily applies only to Cheddar cheese. By
easy use of the last column, the caloric value of this cheese can be
compared with that of any competing food and the relative economy
determined, whatever the price asked. Another recent calculation with
reference[146] to the same cheese follows:
"One pound of American Cheddar cheese contains as much protein as--
1.57 pounds of sirloin steak.
1.35 pounds of round steak.
1.89 pounds of fowl.
1.79 pounds of smoked ham.
1.81 pounds of fresh ham.
"In order to judge the value of foods fairly not only the protein but
the energy also must be compared. To supply energy cheese is one of the
best of food products. On the basis of energy supplied, 1 pound of
cheese equals--
1.98 pounds of sirloin steak.
2.61 pounds of round steak.
2.52 pounds of fowl.
1.17 pounds of smoked ham.
1.29 pounds of fresh ham."
All these discussions have applied to whole-milk Cheddar cheese. With
minor reductions, much the same figures will hold for Swiss, Limburger,
Brick, Munster, Edam.
On the other hand, very little has been published until recently on the
skimmed-milk cheeses. The food value lost in skimmed-milk has at times
been enormous. Many households purchase milk by the bottle, use the
top-milk as cream and lose a part of the remainder. Similarly creameries
have wasted tons of skimmed-milk. The recovery of the protein of this
milk for human food is both good economy and an important addition to
the dietary. The United States Department of Agriculture has recently
published the following: "Cottage cheese is richer in protein than most
meats and is very much cheaper. Every pound contains more than three
ounces of protein, the source of nitrogen for body building. It is a
valuable source of energy also, though not so high as foods with more
fat. It follows that its value in this respect can be greatly increased
by serving it with cream, as is so commonly done."
It is an open question whether the decline of cheese-making in America
is not due to our failure to develop the use of skim and part-skim
cheeses. The whole-milk cheeses are very rich in fat. Use of such cheese
in quantity in connection with ordinary foods quickly leads to the
ingestion of too much fat. The skimmed-milk cheeses are primarily
protein food and as such substitutes for lean meat.
"The following table shows that cottage cheese is much cheaper than
most meats in furnishing protein for the diet.
"For supplying protein, one pound of cottage cheese equals:
1.27 pounds sirloin steak.
1.09 pounds round steak.
1.37 pounds chuck rib beef.
1.52 pounds fowl.
1.46 pounds fresh ham.
1.44 pounds smoked ham.
1.58 pounds loin pork chop.
1.31 pounds hind leg of lamb.
1.37 pounds breast of veal.
"In addition to protein, energy for performing body work must be
furnished by food. As a source of energy also, cottage cheese is cheaper
than most meats at present prices. The following table shows the
comparison when energy is considered.
"On the basis of energy supplied, one pound of cottage cheese equals:
8-1/3 ounces sirloin steak.
11¼ ounces round steak.
11¼ ounces chuck rib beef.
10¾ ounces fowl.
5½ ounces fresh ham.
5 ounces smoked ham.
6 ounces loin pork chop.
7-1/3 ounces hind leg of lamb.
12¾ ounces breast of veal."
+335. Digestibility of cheese.+--Although it has been a staple food with
many races for uncounted years, there is a widespread belief that cheese
is suitable for use chiefly in small quantities as an accessory to the
diet, and that in large quantities it is likely to produce physiological
disturbances. The question of digestibility was made the subject of a
special investigation by the United States Department of
Agriculture.[147] Calorimeter experiments[148] were made to test the
digestibility of several varieties of cheese and some of these varieties
at various stages of ripening. All forms of cheese were found to be
digested as completely as most of the usual forms of food. Approximately
90 per cent of the nitrogenous portion (casein) was retained in the
body. Unripe cheese in these experiments was apparently digested as
completely as the ripened forms. These experiments make clear the
possibility of making cheese a more prominent article in the regular
dietary than is usual in America. They especially point to the
desirability of the use of the skim and partially skim cheeses, which as
cheap sources of protein when properly combined with other foods, may be
made to replace meats as a less costly source of proteins. Cheese is
then to be classed with meat and eggs, not with condiments. An ounce of
Cheddar[149] cheese roughly is equivalent to one egg, to a glass of
milk, or to two ounces of meat. It is properly to be combined with
bread, potatoes and other starchy foods, lacking in the fat in which the
cheese is rich. These experiments included Roquefort, fresh-made and
ripe Cheddar, Swiss, Camembert and Cottage cheese.
+336. Cheese flavor.+--"Cheese owes its flavor to the fatty acids and
their compounds which it contains and to ammonia-like bodies formed
during ripening from the cleavage of the casein, to salt added to the
curd, and in some varieties, like Roquefort, to bodies elaborated by
molds which develop in the cheese. In the highly flavored sorts some of
the fatty acids of a very marked odor are present in abundance, as are
also the ammonia-like bodies. Indeed, in eating such cheese as Camembert
a trace of ammonia flavor may often be plainly detected.
"The cleavage of the nitrogenous material of the cheese and other
changes are brought about chiefly by the action of enzymes originally
present in cheese or by micro-organisms and are to be regarded as
fermentative and not as putrefactive changes.
"The liking for highly flavored cheeses of strong odor is a matter of
individual preference, but from the chemist's standpoint there is no
reason for the statement often made that such cheeses have undergone
putrefactive decomposition."
+337. Relation to health.+--In connection with the use of cheese as a
food, its relation to the health of the consumer must be considered. The
presence of the bacillus of tuberculosis in milk has led to careful
study of its possible presence in cheese. When American Cheddar cheese
was specially inoculated for this purpose, the living organism was
recovered from it after about five months by Schroeder of the United
States Department of Agriculture. This danger is much greater from
cheeses, such as Cream and Neufchâtel, which are eaten when
comparatively freshly made. The disease has been produced in guinea pigs
from such cheese often enough to emphasize the desirability of
developing methods of making every variety possible from thoroughly
pasteurized milk. This would remove the danger of tuberculosis and with
it eliminate the possibility of transmitting other diseases.
+338. Cheese poisoning+[150] cases occasionally occur. These take two
main forms: (1) an enteritis (caused by _Bacillus enteritidis_) or some
other member of that series which while painful and accompanied by
purging is rarely fatal; (2) acute toxæmias which, although rare,
usually result in death. From the latter type a variety of _Bacillus
botulinus_, an organism usually associated with meat poisoning, was
isolated by the New York State Department of Health. The occurrence of
such cases is frequent enough to emphasize the desirability of using
every precaution to reduce the number of bacteria that are allowed to
enter milk when drawn and to prevent the development of those which
actually gain access to it. When possible, pasteurization should be
introduced.
+339. Proper place in the diet.+--It has already been noted that cheese
is used "in general in two ways--in small quantities chiefly for its
flavor and in large quantities for its nutritive value as well as for
its flavor. Some varieties of cheese are used chiefly for the first
purpose, others chiefly for the second. Those which are used chiefly for
their flavor, many of which are high priced, contribute little to the
food value of the diet, because of the small quantity used at a time.
They have an important part to play, however, in making the diet
attractive and palatable. The intelligent housekeeper thinks of them not
as necessities, but as lying within what has been called 'the region of
choice.' Having first satisfied herself that her family is receiving
sufficient nourishment, she then, according to her means and ideas of an
attractive diet, chooses among these foods and others which are to be
considered luxuries.
"Those cheeses, on the other hand, which are suitable to be eaten in
large quantities and which are comparatively low priced are important
not only from the point of view of flavor, but also from the point of
view of their nutritive value." Among such cheeses are American Cheddar,
Swiss, Brick, Limburger and the lower priced forms of Neufchâtel.
It is clear that in buying cheese, the housekeeper should know
definitely the dietary purpose of the purchase, and then choose the
variety of cheese best suited. To a very large degree the personal
tastes of the family determine the kinds of cheese which will be
tolerated when served uncooked. In some families, the strong flavors of
Roquefort or Limburger are not acceptable. However, there is a range of
choice in which much judgment can be used. Cheese to be served with
mild-flavored foods should as a rule be also mild-flavored. For most
sandwiches, for example, Cheddar or Swiss is usually very acceptable;
Brick or partly ripe Limburger still hard enough to slice cuts into thin
rectangular slices and is very attractive to many consumers because it
has somewhat more flavor without being too strong. With proper handling
it is good policy to buy the cheapest of these forms for this purpose.
The selection of dessert cheeses offers the widest range. If served with
mild-flavored crackers, very many persons prefer Cream, Neufchâtel or
mild Cheddar; a little stronger taste calls for club cheese, or
Camembert. If tobacco smoke is present, Roquefort, Gorgonzola, Limburger
and related types will satisfy many consumers better than mild cheeses.
The intensity of flavor to be sought in the cheese should thus be
adjusted to the food served with it. A person with an aversion to
strong-smelling or strong-tasting cheese has been frequently known to
approve over-ripe Camembert, or Limburger when served without label but
spread upon a ginger cracker.
For cooking purposes, some recipes prescribe cheese of special quality.
In large markets, old Cheddar ripened carefully for two or three years
is commonly purchasable for Welsh rabbit. (Ask for "rabbit" cheese.) An
expert housekeeper familiar also with cheese ripening has demonstrated
that almost any cheese, whether ripened to its best, part ripe or
over-ripe, can be used in many cooking formulas without injuring the
acceptability of the product to most consumers. In canning Camembert, it
has been shown[151] that over-ripe cheese so strong as to be
objectionable, when sterilized loses the objectionable flavor of the raw
product. No cheese should be wasted; any not used when served the first
time should be served at a closely following meal or used in cooking. No
matter what the variety, it will add to the food value and palatability
of some one of the common dishes served within forty-eight hours.
+340. Care of cheese.+[152]--"One of the best ways of keeping cheese
which has been cut is to wrap it in a slightly damp cloth and then in
paper, and to keep it in a cool place. To dampen the cloth, sprinkle it
and then wring it. It should seem hardly damp to the touch. Paraffin
paper may be used in place of the cloth. When cheese is put in a covered
dish, the air should never be wholly excluded, for if this is done, it
molds more readily.
"In some markets it is possible to buy small whole cheeses. These may be
satisfactorily kept by cutting a slice from the top, to serve as a
cover, and removing the cheese as needed with a knife, a strong spoon,
or a cheese scoop. It is possible to buy at the hardware stores knobs
which inserted in the layer cut from the top make it easy to handle.
The cheese with the cover on should be kept wrapped in a cloth."
+341. Food value and price.+--There is little relation between the price
and food value of standard varieties of cheese. The higher-priced
varieties claim and hold their place because they possess particular
flavors. These may or may not accompany high comparative food values.
Even among low-priced varieties discrimination into grades is largely
based on flavor. Of the low-priced cheeses, those made from skimmed-milk
commonly command the lowest prices. As noted above, a choice may be
based either on purpose or on price. If the purpose is fixed, the price
should not change the selection. If, however, a particular quality of
cheese is purchasable at a low price, some satisfactory form of
utilizing it is clearly available to the housekeeper. Some standard
recipes are given in the following paragraphs.
+342. Methods and recipes for using cheese.+--(1) As a meat substitute.
Meat is wholesome and relished by most persons, yet it is not essential
to a well-balanced meal and there are many housekeepers who for one
reason or another are interested in lessening the amount of meat or to
substitute other foods. The problem with the average family is
undoubtedly more often the occasional substitution of other palatable
dishes for the sake of variety, for reasons of economy, or for some
other reason than the general replacement of meat dishes by other
things.
Foods which are to be served in place of meat should be rich in protein
and fat and should also be savory. Cheese naturally suggests itself as a
substitute for meat, since it is rich in the same kinds of nutrients
that meat supplies, is a staple food with which every one is familiar
and is one which can be used in a great variety of ways. In
substituting cheese for meat, especial pains should be taken to serve
dishes which are relished by the members of the family. A number of
recipes[153] for dishes which contain cheese are given below. They are
preceded by several recipes for cheese sauces which, as will appear, are
called for in the preparation of some of the more substantial dishes. In
the first list of recipes, cheese means Cheddar.
Cheese Sauce No. 1
1 cupful of milk.
2 tablespoonfuls of flour.
1 ounce of cheese (¼ cupful of grated cheese).
Salt and pepper.
Thicken the milk with the flour and just before serving
add the cheese, stirring until it is melted.
This sauce is suitable to use in preparing creamed eggs,
or to pour over toast, making a dish corresponding to
ordinary milk toast, except for the presence of cheese. It
may be seasoned with a little curry powder and poured over
hard-boiled eggs.
Cheese Sauce No. 2
Same as cheese sauce No. 1, except that the cheese is
increased from 1 to 2 ounces.
This sauce is suitable for using with macaroni or rice, or
for baking with crackers soaked in milk.
Cheese Sauce No. 3
Same as cheese sauce No. 1, except that two cupfuls of
grated cheese or 8 ounces are used. This may be used upon
toast as a substitute for Welsh rabbit.
Cheese Sauce No. 4
Same as cheese sauce No. 2, save that 2 tablespoonfuls of
melted butter are mixed with the flour before the latter
is put into the milk. This sauce is therefore very rich in
fat and has only a mild flavor of cheese.
Among the recipes for dishes which may be used like meat, the following
give products which, eaten in usual quantities, will provide much the
same kind and amount of nutritive material as the ordinary servings of
meat dishes used at dinner. In several cases there is a resemblance in
appearance and flavor to common meat dishes, which would doubtless be a
point in their favor with many families.
(2) For general cooking purposes:
Cheese Fondue No. 1
1-1/3 cupfuls of soft, stale bread crumbs.
6 ounces of cheese (1½ cupfuls of grated cheese or
1-1/3 cupfuls of cheese grated fine or cut into small
pieces).
4 eggs.
1 cupful of hot water.
½ teaspoonful of salt.
Mix the water, bread crumbs, salt and cheese; add the yolks
thoroughly beaten; into this mixture cut and fold the whites of
eggs beaten until stiff. Pour into a buttered baking dish and
cook 30 minutes in a moderate oven. Serve at once.
The food value of this dish, made with the above quantities,
is almost exactly the same as that of a pound of beef of average
composition and a pound of potatoes combined. It contains
about 80 grams of proteids and has a fuel value of about 1300
calories.
Cheese Fondue No. 2
1-1/3 cupfuls of hot milk.
1-1/3 cupfuls of soft, stale bread crumbs.
1 tablespoonful of butter.
4 eggs.
1/3 of a pound of cheese (1-1/3 cupfuls of grated cheese
or 1 cupful of cheese cut into small pieces).
½ teaspoonful of salt.
Prepare as in previous recipe.
The protein value of this dish is equal to that of 1-1/8 pounds of
potato and beef, the fuel value, however, being much in excess of these.
In making either of these fondues, rice or other cereals may be
substituted for bread crumbs. One-fourth cupful of rice measured before
cooking, or one cupful of cooked rice or other cereals, should be used.
Corn and Cheese Soufflé
1 tablespoonful of butter.
1 tablespoonful of chopped green pepper.
¼ cupful of flour.
2 cupfuls of milk.
1 cupful of chopped corn.
1 cupful of grated cheese,
3 eggs.
½ teaspoonful of salt.
Melt the butter and cook the pepper thoroughly in it. Make
a sauce out of the flour, milk and cheese; add the corn,
cheese, yolks and seasoning; cut and fold in the whites
beaten stiffly; turn into a buttered baking dish and bake
in a moderate oven 30 minutes.
Made with skimmed-milk and without butter, this dish has a
food value slightly in excess of a pound of beef and a
pound of potatoes.
Cheese Soufflé
2 tablespoonfuls of butter.
3 tablespoonfuls of flour.
½ cupful of milk (scalded).
½ teaspoonful of salt
A speck of cayenne.
¼ cupful of grated cheese.
3 eggs.
Melt the butter; add the flour and, when well mixed, add
gradually the scalded milk. Then add salt, cayenne and
cheese. Remove from the fire and add the yolks of the
eggs, beaten until lemon colored. Cool the mixture and
fold into it the whites of the eggs, beaten until stiff.
Pour into a buttered baking dish and cook 20 minutes in a
slow oven. Serve at once.
The proteid of this recipe is equal to that of half a
pound of beef; the fuel value is equal to that of
three-fourths of a pound.
Welsh Rabbit
1 tablespoonful of butter.
1 teaspoonful of corn-starch.
½ cupful of milk.
½ pound of cheese, cut into small pieces.
¼ teaspoonful each of salt and mustard.
A speck of cayenne pepper.
Cook the corn-starch in the butter; then add the milk
gradually and cook two minutes; add the cheese and stir
until it is melted. Season and serve on crackers or bread
toasted on one side, the rabbit being poured over the
untoasted side. Food value is that of about three-fourths
of a pound of beef.
Macaroni and Cheese No. 1
1 cupful of macaroni, broken into small pieces.
2 quarts of boiling salted water.
1 cupful of milk.
2 tablespoonfuls of flour.
¼ to ½ pound of cheese.
½ teaspoonful of salt.
Speck of cayenne pepper.
Cook the macaroni in the boiling salted water, drain in a
strainer, and pour cold water over it to prevent the
pieces from adhering to each other. Make a sauce out of
the flour, milk, and cheese. Put the sauce and macaroni in
alternate layers in a buttered baking dish, cover with
buttered crumbs, and heat in oven until crumbs are brown.
Macaroni and Cheese No. 2
A good way to prepare macaroni and cheese is to make a
rich cheese sauce and heat the macaroni in it. The mixture
is usually covered with buttered crumbs and browned in the
oven. The advantage of this way of preparing the dish,
however, is that it is unnecessary to have a hot oven, as
the sauce and macaroni may be reheated on the top of the
stove.
Baked Rice and Cheese No. 1
1 cupful of uncooked rice and
4 cupfuls of milk;
or,
3 cupfuls of cooked rice and
1 cupful of milk.
2 tablespoonfuls of flour.
½ pound of cheese.
½ teaspoonful of salt.
If uncooked rice is used, it should be cooked in 3 cupfuls
of milk. Make a sauce with one cupful of milk, add the
flour, cheese and salt. Into a buttered baking dish put
alternate layers of the cooked rice and the sauce. Cover
with buttered crumbs and bake until the crumbs are brown.
The proteids in this dish, made with rice cooked in milk,
are equal to those of nearly 1¾ pounds of average beef.
If skimmed-milk is used, the fuel value is equal to nearly
3½ pounds of beef. Whole milk raises the fuel value
still higher.
Fried Bread with Cheese No. 1
6 slices of bread.
1 cupful of milk.
2 ounces of cheese, or ½ cupful of grated cheese.
½ teaspoonful of salt.
½ teaspoonful of potassium bicarbonate.
Butter or other fat for frying.
Scald the milk with the potassium bicarbonate; add the
grated cheese, and stir until it dissolves. Dip the bread
in this mixture and fry it in the butter. The potassium
bicarbonate helps to keep the cheese in solution. It is
desirable, however, to keep the milk hot while the bread
is being dipped.
Plain Cheese Salad
Cut Edam or ordinary American cheese into thin pieces,
scatter them over lettuce leaves and serve with French
dressing.
Olive and Pimiento Sandwich or Salad Cheese
Mash any of the soft cream cheeses and add chopped olives
and pimientos in equal parts. This mixture requires much
salt to make it palatable to most palates, the amount
depending chiefly on the quantity of pimiento used. The
mixture may be spread between thin slices of bread or it
may be made into a roll or molded, cut into slices and
served on lettuce leaves with French dressing.
Cheese and Tomato Salad
Stuff cold tomatoes with cream cheese and serve on lettuce
leaves with French dressing.
Cheese and Pimiento Salad
Stuff canned pimientos with cream cheese, cut into slices
and serve one or two slices to each person on lettuce
leaves with French dressing.
(3) Ways to use cottage cheese. Cottage cheese alone is an
appetizing and nutritious dish. It may also be served with
sweet or sour cream, and some persons add a little sugar,
or chives, chopped onion or caraway seed.
The following recipes[154] illustrate a number of ways in
which cottage cheese may be served:
Cottage Cheese with Preserves and Jellies
Pour over cottage cheese any fruit preserves, such as
strawberries, figs or cherries. Serve with bread or
crackers. If preferred, cottage cheese balls may be served
separately and eaten with the preserves. A very attractive
dish may be made by dropping a bit of jelly into a nest of
the cottage cheese.
Cottage Cheese Salad
Mix thoroughly one pound of cheese, one and one-half
tablespoonfuls of cream, one tablespoonful of chopped
parsley and salt to taste. First, fill a rectangular tin
mold with cold water to chill and wet the surface; line
the bottom with waxed paper, then pack in three layers of
the cheese, putting two or three parallel strips of
pimiento, fresh or canned, between the layers. Cover with
waxed paper and set in a cool place until ready to serve;
then run a knife around the sides and invert the mold. Cut
in slices and serve on lettuce leaves with French dressing
and wafers or thin bread-and-butter sandwiches. Minced
olives may be used instead of the parsley, and chopped
nuts also may be added.
Cottage Cheese Rolls
(To be used like meat rolls.)
A large variety of rolls, suitable for serving as the main
dish at dinner, may be made by combining legumes (beans of
various kinds, cowpeas, lentils or peas) with cottage
cheese, and adding bread crumbs to make the mixture thick
enough to form into a roll. Beans are usually mashed, but
peas or small Lima beans may be combined whole with bread
crumbs and cottage cheese, and enough of the liquor in
which the vegetables have been cooked should be added to
get the right consistency; or, instead of beans or peas,
chopped spinach, beet tops or head lettuce may be added.
Boston Roast
1 pound can of kidney beans, or equivalent quantity of cooked beans.
½ pound of cottage cheese.
Bread crumbs.
Salt.
Mash the beans or put them through a meat grinder. Add the
cheese and bread crumbs enough to make the mixture
sufficiently stiff to be formed into a roll. Bake in a
moderate oven, basting occasionally with butter or other
fat, and water. Serve with tomato sauce. This dish may be
flavored with chopped onions cooked until tender in butter
or other fat and a very little water.
Pimiento and Cottage Cheese Roast
2 cupfuls of cooked Lima beans.
¼ pound of cottage cheese.
Salt.
3 canned pimientos chopped.
Bread crumbs.
Put the first three ingredients through a meat chopper.
Mix thoroughly and add bread crumbs until it is stiff
enough to form into a roll. Brown in the oven, basting
occasionally with butter or other fat, and water.
Cottage Cheese and Nut Roast
1 cupful of cottage cheese.
1 cupful of chopped English walnuts.
1 cupful of bread crumbs.
Salt and pepper.
2 tablespoonfuls of chopped onion.
1 tablespoonful of butter.
Juice of half a lemon.
Cook the onion in the butter or other fat and a little
water until tender. Mix the other ingredients and moisten
with the water in which the onion has been cooked. Pour
into a shallow baking dish and brown in the oven.
Cheese Sauce
(For use with eggs, milk toast or other dishes.)
One cupful of milk, 1 tablespoonful of cottage cheese, 2
tablespoonfuls of flour, salt and pepper to taste.
Thicken the milk with the flour and just before serving
add the cheese, stirring until it is melted.
This sauce may be used in preparing creamed eggs or for
ordinary milk toast. The quantity of cheese in the recipe
may be increased, making a sauce suitable for using with
macaroni or rice.
FOOTNOTES:
[1] Ont. Exp. Sta. Rept. 1890, pages 237-241.
Maine Exp. Sta. Rept. 1890, part II, pages 52-57.
Conn. (Storrs) Exp. Sta. Rept. 1886, pages 119-130.
Vt. Exp. Sta. Rept. 1890, pages 97-100.
Vt. Exp. Sta. Rept. 1891, pages 61-74.
N. Y. Exp. Sta. Rept. 1892, pages 299-392.
N. Y. Exp. Sta. Rept. 1893, pages 39-162.
Wis. Exp. Sta. Rept. 1890, pages 115-119.
Conn. (Storrs) Exp. Sta. Rept. 1907, pages 152-156.
N. Y. Exp. Sta. Rept. 1891, pages 139-142.
N. Y. Exp. Sta. Rept. 1894, pages 31-86, 118-121.
N. J. Exp. Sta. Rept. 1895, pages 136-137.
Eckles, C. H., and R. H. Shaw. The influence of breed and
individuality on the composition and properties of milk,
Bur. An. Ind. Bul. 156, 1913. Eckles, C. H., and R. H.
Shaw, Variations in the composition and properties of milk
from the individual cow, U. S. Dept. Agr. Bur. An. Ind.
Bul. 157, 1913.
[2] Morrow, G. A., and A. G. Manns, Analyses of milk from different
cows, Ill. Exp. Sta. Bul. 9, 1890.
[3] Eckles, C. H., and R. H. Shaw, The influence of the stage of
lactation on the composition and properties of milk, U.
S. Dept. Agr. Bur. An. Ind. Bul. 155, 1913. N. Y. Exp.
Sta. Rept. 1892, pages 138-140.
[4] N. Y. Exp. Sta. Rept. 1891, pages 143-162, 316-318.
Wis. Exp. Sta. Rept. 1890, pages 238-247.
Van Slyke, L. L., Conditions affecting the proportions
of fat and protein in cow's milk, Jour. Am. Chem. Soc.,
30 (1908), no. 7, pages 1166-1186.
[5] Van Slyke, L. L., and A. W. Bosworth, Composition and
properties of some casein and paracasein compounds and
their relations to cheese, N. Y. Exp. Sta. Tech. Bul.
26, 1912.
Forbes, E. B., and M. H. Keith, A review of the
literature of phosphorus compounds in animal metabolism,
Ohio Exp. Sta. Tech. Bul. 5, pages 32-36, 42-45.
Van Slyke, L. L., and A. W. Bosworth, Condition of
casein and salts in milk, N. Y. Exp. Sta. Tech. Bul. 39.
[6] Wis. Exp. Sta. Rept. 1901, pages 162-166.
[7] Sammis, J. L., and A. T. Bruhn, The manufacture of cheese
from pasteurized milk, Wis. Exp. Sta. Research Bul. 27, 1912.
[8] Baer, U. S., and W. L. Carlyle, Quality of cheese as affected
by food, Wis. Exp. Sta. Bul. 115, 1904.
[9] King, F. H., and E. H. Farrington, Milk odor as affected by
silage, Wis. Exp. Sta. Bul. 59, 1897.
[10] N. Y. Agricultural Law, 1913, section 30.
Mich. Agricultural Law, 1915, section 77.
Wis. Agricultural Law, 1913, section 4601.
[11] Conn. (Storrs) Exp. Sta. Rept. 1899, pages 13-68.
Conn. (Storrs) Exp. Sta. Rept. 1903, pages 33-98.
Conn. (Storrs) Exp. Sta. Rept. 1904, pages 27-88.
Esten, W. M., and C. J. Mason, Sources of bacteria in
milk, Conn. (Storrs) Exp. Sta. Bul. 51, 1908.
Rogers, L. A., and B. J. Davis, Methods of classifying
the lactic acid bacteria, U. S. Dept. Agr. Bur. An. Ind.
Bul. 154, 1912.
Bergey, D. H., The colon-aerogenes group of bacteria,
Jour. Med. Research, Boston, Vol. XIX, pages 175-200,
1908.
Conn, H. W., Classification of dairy bacteria, Conn.
(Storrs) Exp. Sta. Rept. 1906.
Rogers, L. A., Bacteria in milk, U. S. Dept. Agr.,
Farmers' Bul. 490, 1912.
[12] Hastings, E. G., Distribution of lactose-fermenting yeasts
in dairy products, Wis. Exp. Sta. Rept. 23, pages
107-115.
[13] Thom, C., and S. H. Ayers, Effect of pasteurization upon
mold spores, Jour. Agr. Research 6 (1916), no. 4, pages
153-156.
[14] Hunziker, O. F., Germicidal action of milk, N. Y. (Cornell)
Exp. Sta. Bul. 197.
Stocking, W. A., Germicidal action of milk, Conn.
(Storrs) Exp. Sta. Bul. 37, 1905.
U. S. Treasury Dept., Hygienic Laboratory, Bul. 41,
Milk and its relation to the public health, 1908, also
revised as Bul. 56, 1909.
[15] U. S. Dept. Agr., Farmers' Bul. 602, Dairy Division,
Production of clean milk, 1914.
Lauder, A., and A. Cunningham, Some factors affecting
the bacteriological content of milk, Edinburgh and East
of Scotland Coll. of Agr. Rept. XXVIII, 1913.
Prucha, M. J., and H. M. Weeter, Germ content of milk,
Ill. Exp. Sta. Bul. 199, 1917.
Harding, H. A., _et al._, The effect of certain dairy
operations upon the germ content of milk, N. Y. Exp.
Sta. Bul. 365, 1913.
Fraser, W. J., Sources of bacteria in milk, Ill. Exp.
Sta. Bul. 91, 1903.
Frandsen, J. H., Care of milk and cream on the farm,
Neb. Exp. Sta. Bul. 133, 1912.
Conn, H. W., The care and handling of milk, Conn.
(Storrs) Exp. Sta. Bul. 26, 1903.
Stocking, W. A., Jr., Quality of milk as affected by
certain dairy operations, Conn. (Storrs) Exp. Sta. Bul.
42, 1906.
[16] Harding, H. A., J. K. Wilson and G. A. Smith, Tests of
covered milk pails, N. Y. Exp. Sta. Bul. 326, 1910.
Stocking, W. A., Tests of covered milk pails, Conn.
(Storrs) Exp. Sta. Bul. 48, 1907.
[17] Wing, L. W., Milking machines; their sterilization and their
efficiency in producing clean milk, N. Y. (Cornell)
Exp. Sta. Circ. 18, 1913.
[18] Ruddick, J. A., and G. H. Barr, The cooling of milk for
cheese making, Ottawa Dept. of Agr. Bul. 22, 1910.
[19] Wis. Exp. Sta. Rept. 1895, pages 14-150, Fermentation test
for gas-producing bacteria in milk. This is commonly
called the Wisconsin curd test.
[20] Stevenson, C., Pepsin in cheesemaking, Jour. Agr. (New
Zeal.) 14 (1917), pages 32-34.
Todd, A., and E. C. V. Cornish, Experiments in the
preparation of homemade rennet, Jour. Bd. Agr. (London)
23 (1916), no. 6, pages 549-555.
Besana, C., Lack of coagulating ferment in
cheesemaking, Staz. Sper. Agr. Ital. 49 (1916), pages
10-12.
Van Dam, W., Rennet economy and substitutes, Verslag.
Ver. Exploit. Proefzuivelboerderij. Hoorn, 1914, pages
45-46.
[21] The paragraphs on the chemistry of casein and on rennet
action have been selected from a complete discussion of
the subject by E. B. Forbes and M. H. Keith in Ohio
Exp. Sta. Tech. Bul. 5 entitled, "A review of the
literature of phosphorus compounds in animal
metabolism." The original references cited in this
discussion are given at the end of the chapter in the
order of their citation in the text.
See also, Van Slyke, L. L., and D. D. Van Slyke, I, The
action of dilute acids upon casein when no soluble
compounds are formed; II, The hydrolyses of the sodium
salts of casein, N. Y. (Geneva) Exp. Sta. Tech. Bul. 3,
pages 75-162, 1906.
Sammis, J. L., S. K. Suzuki and F. W. Laabs, Factors
controlling the moisture content of cheese curds, U. S.
Dept. Agr. Bur. An. Ind. Bul. 122, pages 1-61, 1910.
[22] Sammis, J. L., and A. T. Bruhn, The manufacture of Cheddar
cheese from pasteurized milk, Wis. Exp. Sta. Research
Bul. 27, 1912.
[23] Esten, W. M., Bacteria in the dairy, Conn. (Storrs) Rept.
1896, pages 44-52.
[24] Bushnell, L. D., and W. R. Wright, Preparation and use of
butter starter, Mich. Exp. Sta. Bul. 246, 1907.
Hastings, E. G., Preparation and use of starter, Wis.
Exp. Sta. Bul. 181, 1909.
Larsen, C., and W. White, Preparation and use of
starter, S. D. Exp. Sta. Bul. 123, 1910.
Guthrie, E. S., and W. W. Fisk, Propagation of starter
for butter-making and cheese-making, N. Y. (Cornell)
Exp. Sta. Circ. 13, 1912.
[25] Sammis, J. L., and A. T. Bruhn, The manufacture of cheese of
the Cheddar type from pasteurized milk, U. S. Dept.
Agr. Bur. An. Ind. Bul. 165, pages 1-95, 1913.
[26] Publow, C. A., An apparatus for measuring acidity in
cheesemaking and buttermaking, Cornell Exp. Sta. Circ.
7, pages 17-20, 1909.
Hastings, E. G., and A. C. Evans, A comparison of the
acid test and the rennet test for determining the
condition of milk for the Cheddar type of cheese, U. S.
Dept. Agr. Bur. An. Ind. Circ. 210, pages 1-6, 1913.
[27] Doane, C. F., The influence of lactic acid on the quality of
cheese of the Cheddar type, U. S. Dept. Agr. Bur. An.
Ind. Bul. 123, pages 1-20, 1910.
[28] Fisk, W. W., A study of some factors influencing the yield
and moisture content of Cheddar cheese, Cornell Exp.
Sta. Bul. 334, 1913.
[29] Olson, G. A., Rusty cans and their effect upon milk for
cheese-making, Wis. Exp. Sta. Bul. 162, pages 1-12,
1908.
[30] The term "broken" is included here because the use of some
curd-breaking tool has always formed a step in certain
commercially successful processes. In every case in
which careful experimental work has been done the curd
knife has been successfully substituted for the
breaking tool and has reduced the losses of fat and
casein and in addition aided in obtaining more uniform
cheese.
[31] Frandsen, J. H., and T. Thorsen, Farm cheese-making,
Univ. Neb. Ext. Serv. Bul. 47, pages 1-16, 1917.
Michels, J., Improved methods for making cottage and
Neufchâtel cheese, N. C. Exp. Sta. Bul. 210, pages
29-38.
Fisk, W. W., Methods of making some of the soft
cheeses, Cornell Exp. Sta. Circ. 30, pages 41-62, 1915.
[32] Tolstrup, R. M., Cheese that farmers should make, Iowa
Agr. 15 (1914), 2, pages 89-90.
[33] Van Slyke, L. L., and Hart, E. B., Chemical changes in
the souring of milk and their relations to cottage
cheese, N. Y. (Geneva) Exp. Sta. Bul. 245, pages 1-36,
1904.
[34] Sammis, J. L., Three creamery methods for making
buttermilk cheese, Wis. Exp. Sta. Bul. 239, 1914.
[35] Matheson, K. J., C. Thom and J. N. Currie, Cheeses of
the Neufchâtel group, Conn. (Storrs) Exp. Sta. Bul. 78,
pages 313-329, 1914.
[36] Dahlberg, A. O., The manufacture of cottage cheese in
creameries and milk plants, U. S. Dept. Agr. Bul. 576,
pages 1-16, 1917.
[37] Since the number of factories has continued small, the
manufacture of this type of machine has remained a
monopoly in which each machine is made to order by the
Van Eyck Machine Co. of Holland, Mich.
[38] Presented by Dr. E. C. Schroeder of the U. S. Dept.
Agr. to the International Association of Dairy and Milk
Inspectors, at Washington, Oct. 17, 1917, published
Jour. Am. Vet. Med. Assoc'n 52, N. S. 5, no. 6, pages
674-685, 1918.
[39] Matheson, K. J., and F. R. Cammack, How to make cottage
cheese on the farm, U. S. Dept. Agr., Farmers' Bul.
850, pages 1-15, 1917.
[40] Taken from Conn. (Storrs) Exp. Sta. Bul. 78, page 328.
[41] Taken from Conn. (Storrs) Exp. Sta. Bul. 78, page 328.
[42] Eckles, C. H., and O. Rahn, Die Reifung des Harzkäses,
Centralb. f. Bakt. etc. 2 abt. 14 (1905), pages
676-680.
[43] Monrad, J. H., Hand cheese, N. Y. Produce Rev. etc. 25
(1908), 16, page 644.
[44] The authors are under obligations to Mrs. E. E. Kiernan
for her description of this process (in the _Somerset
County Leader_, Jan. 10, 1908) and her letters
concerning it. The statement of the process given here
combines the published statement with the results of
our own experiments.
[45] Monrad, J. H., Appetitost, N. Y. Produce Rev. etc. 25
(1908), 16, page 644.
[46] Pouriau, A. F., La Laiterie, sixième ed. par Marcel
Monteran, page 453, Paris, 1908.
[47] Among the varietal names for Neufchâtel cheese from
whole milk or with added cream are Petits Bondons,
Malakoffs, Carrés affinés. Among low fat or skim forms,
Petit Suisse, Gournay.
[48] Thom, C., J. N. Currie and K. J. Matheson, Studies
relating to the Roquefort and Camembert types of
cheese, Conn. (Storrs) Exp. Sta. Bul. 79, page 392.
[49] Full discussion of this product is found in U. S. Dept.
Agr. Bur. An. Ind. Bul. 115. Camembert cheese problems
in the U. S. also published as Storrs Exp. Sta. Bul. 58
with the same title. Also a supplementary paper in Bul.
79 of Storrs Exp. Sta.
[50] Thom, C., U. S. Dept. Agr. Bur. An. Ind. Circ. 145
(1909), page 339.
[51] Lot record cards for the making and ripening of
Camembert are given on pages 124 and 125.
[52] Bosworth, A. W., Chemical studies of Camembert cheese,
N. Y. (Geneva) Exp. Sta. Tech. Bul. 5, pages 23-39,
1907.
Dox, A. W., Proteolytic changes in the ripening of Camembert
cheese, U. S. Dept. Agr. Bur. An. Ind. Bul. 109, pages
1-24, 1908.
[53] Esten, W. M., and C. J. Mason, Bact. Stud. of Camembert
cheese, Storrs Exp. Sta. Bul. 83 (1915), pages 103-111.
[54] See page 134 for domestic or American use of the name
Brie.
[55] McNaughton, J., Coulommier cheese, Dept. Agr. Ottawa,
Canada, Dairy and Cold Storage Ser. Bul. 25, 1910.
[56] Kosher forms are prepared in compliance with the Mosaic
law as demanded by the Jewish trade.
[57] Unpublished analysis of the Storrs Exp. Sta.
[58] Chapais, J. C., Monographie, Le Fromage Raffiné de L'Isle
d'Orléans. Quebec, 1911. Published by Ministry of
Agriculture, pages 1-31.
[59] The authors acknowledge the assistance of Mr. Louis
Getman in preparing this description.
[60] Zumkehr, P., Limburger cheesemaking, Wis. Cheese-makers
Association, 15th Annual Meeting, 1907, page 62.
[61] Currie, J. N., Flavor of Roquefort cheese, Jour. Agr.
Research 2 (1914), no. 1, pages 1-14.
[62] Wis. Cheese-makers Assoc., 12th Annual Meeting and
Report, 1906, page xxviii.
[63] Currie, J. N., The relation of composition to quality
in cheese, American Food Jour. 11 (1916), no. 9, page
458. See also Dox on the True Composition of Roquefort
Cheese, Ztsch. Untersuch. Nahr. u. Genussmtl. 22
(1911), pages 239-242.
[64] Thom, C., and Matheson, K. J., Biology of Roquefort
cheese, Storrs Exp. Sta. Bul. 79, pages 335-347, 1914.
[65] Currie, J. N., Flavor of Roquefort cheese, Jour. Agr.
Research, 2 (1914), 1, pages 1-14, Washington.
[66] Dox, A. W., Die Zusammensetzung des echten
Roquefort-Käses, in Ztschr. Untersuch. Nahr. u.
Genussmtl. Bd. 22, Heft. 4, pages 239-242, 1911.
[67] Marre, E., Le Roquefort, Rodez, 1906. This is the
authoritative monograph on Roquefort cheese problems.
[68] Reported on the word of Prof. Fleischmann.
[69] Thom, C., J. N. Currie and K. J. Matheson, Studies
relating to the Roquefort and Camembert types of
cheese, Storrs Exp. Sta. Bul. 79, pages 335-394, 1914.
[70] Thom, C., U. S. Dept. Agr. Bur. An. Ind. Bul. 82, 1905.
[71] Thom, C., The salt factor in the mold ripened cheeses,
Storrs Exp. Sta. Bul. 79, pages 387-394, 1914.
[72] Thom, C., and Currie, J. N., The dominance of Roquefort
mold in cheese, Jour. Biol. Chem. 15 (1913), no. 2,
pages 247-258.
[73] Currie, J. N., The composition of Roquefort cheese fat,
Jour. Agr. Research, 2 (1914), 6, pages 429-434.
[74] Thom, C., Soft cheese studies in Europe, U. S. Dept.
Agr. Bur. An. Ind. Rept. 22, pages 79-109, 1905.
[75] Frestadius, A., Nord. Mejeri Tid. 17 (1912), 14, page
159, Abs. N. Y. Produce Rev. 34 (1912), 2, page 54, and
Cutting, W. B., The use of baritine in cheese rinds,
Mo. Commerce and Trade Repts. 1908, 337, page 144, also
in Practical Dairyman, 2 (1908), 7, page 76.
[76] Stilton Cheese--J. P. Sheldon--from abs. by New York
Produce Rev. 28 (June 16, 1909), no. 8, pages 362-363.
Stilton is said to have originated with Mrs. Paulet,
Wymondham, Co. of Leicester, and to have been sold by
her brother--Host of the "Bill" at Stilton from which
village it derived its name.
[77] Percival, J., and G. Heather Mason, The microflora of
Stilton cheese, Jour. Agr. Sci. 5 (1913), part 2, pages
222-229. See also Thom, C., Soft cheese studies in
Europe, U. S. Dept. Agr. Bur. An. Ind. Rept. 22 (1905),
pages 79-109.
[78] Benson, Miles, in personal letter from analyses of
cheeses selected for the purpose.
[79] Dean, H. H., The Creamery Journal, Nov. 1904.
[80] N. Y. Produce Rev. etc., Vol. 32, no. 14, page 536.
[81] N. Y. Produce Rev. etc., Vol. 30, no. 5, page 188; Vol.
30, no. 14, page 534; Vol. 31, no. 5, page 182.
Marty, G., Brick cheesemaking, Wis. Cheese-makers
Assoc., 15th Annual Meeting, 1907, page 66.
Wuethrich, F., The manufacture of Brick cheese, Wis.
Cheese-makers Assoc., 14th Annual Meeting, 1906, page
50.
Schenk, C., Brick cheesemaking, Wis. Cheese-makers
Assoc., 13th Annual Meeting, 1905, page 38.
[82] Doane, C. F., and H. W. Lawson, Varieties of cheese,
descriptions and analysis, U. S. Dept. Agr. Bur. of An.
Ind. Bul. 146, 1911.
[83] Ligeon, X., Herstellung des Port Salut Käses, Milchztg.
38 (1909), no. 39, pages 459-460.
[84] These paragraphs were taken from N. Y. Exp. Sta. Bul.
56, Experiments in the manufacture of cheese; Part I.
The manufacture of Edam cheese, 1893. See also,
Haecker, T. L., Experiments in the manufacture of
cheese, Minn. Exp. Sta. Bul. 35, 1894.
[85] Boekhout, F. W. J., and J. J. O. de Vries, Cracking of
Edam, Verslag. Landbouwk. Onderzoek.
Rykslandboupoefstat. (Netherlands), 20 (1917), pages
71-78, fig. 1.
Boekhout, F. W. F., and J. J. O. de Vries, Sur le
défaut "Knijpers" dans le fromage d'Edam, Rev. Gen.
Lait, 9 (1913), no. 18, pages 420-427.
[86] Paragraphs taken from N. Y. Exp. Sta. Bul. 56,
Experiments in the manufacture of cheese; Part II. The
manufacture of Gouda cheese, 1893. See also, Hayward,
H., Method of making Gouda cheese, Pa. Exp. Sta. Rept.
1890, pages 79-81, and Haecker, T. L., Experiments in
the manufacture of cheese, Minn. Exp. Sta. Bul. 35,
1894, and Monrad, J. H., in N. Y. Produce Rev. 25
(1907), no. 8, page 336, where a home process of making
this cheese is given.
[87] The authors acknowledge here the helpful suggestions
and criticisms of G. C. Dutton, New York State Cheese
Instructor.
[88] Russell, H. L., Cheese as affected by gas-producing
bacteria, Wis. Exp. Sta. Rept. 1895, pages 139-146.
Marshall, C. E., Gassy curd and cheese, Mich. Exp. Sta.
Bul. 183, 1900.
[89] S. M. Babcock, Hot iron test of cheese curd, Wis. Exp.
Sta. Rept. 1895, pages 133-134.
[90] Van Slyke, L. L., and E. B. Hart, A study of some of
the salts formed by casein and paracasein with acids,
their relation to American Cheddar cheese, N. Y.
(Geneva) Exp. Sta. Bul. 214, 1902.
[91] Decker, J. W., Cheesemaking from sour milk, Wis. Exp.
Sta. Rept. 1898, pages 42-44.
[92] Russell, H. L., Cheese as affected by gas producing
bacteria, Wis. Exp. Sta. Rept. 1895, pages 139-146.
Marshall, C. E., Gassy curd and cheese, Mich. Exp. Sta.
Bul. 183, 1900.
Moore, V. A., and A. R. Ward, Causes of tainted cheese
curds, N. Y. (Cornell) Exp. Sta. Bul. 158, 1899.
[93] Van Slyke, L. L., Investigations relating to the
manufacture of cheese, N. Y. (Geneva) Exp. Sta. Bul.
68, 1894.
[94] Van Slyke, L. L., Investigations relating to the
manufacture of cheese, N. Y. (Geneva) Exp. Sta. Bul.
62, 1893.
[95] Van Slyke, L. L., Methods of paying for milk at cheese
factories, N. Y. (Geneva) Exp. Sta. Bul. 308, 1908.
[96] Farm Bur. Exchange, St. Lawrence Co., N. Y., Vol. 1,
no. 9, 1915. Cooling milk before delivery at the cheese
factory.
[97] Sammis, J. L., et al., Factors controlling the moisture
content of cheese curds, Wis. Exp. Sta. Research Bul.
7, 1910.
Ont. Agr. College and Exp. Farm Rept. 1909, pages
111-124, Cheese making experiments.
Ont. Agr. College and Exp. Farm Rept. 1910, pages
111-128, Cheese making experiments.
Fisk, W. W., A study of some factors influencing the
yield and the moisture content of Cheddar cheese,
Cornell Exp. Sta. Bul. 334, pages 515-537, 1913.
[98] Sammis, J. L., and A. T. Bruhn, The manufacture of
cheese of the Cheddar type from pasteurized milk, U. S.
Dept. Agr. Bur. An. Ind. Bul. 165, pages 1-95, 1913.
[99] New York Prod. Review, Vol. 34, no. 2, page 66.
[100] Babcock, S. M., _et al._, Cheese ripening as
influenced by sugar, Wis. Exp. Sta. Rept. 1901, pages
162-167.
E. G. Hastings, _et al._, Studies on the factors
concerned in the ripening of Cheddar cheese, Wis. Exp.
Sta. Research Bul. 25.
[101] Fisk, W. W., Skim-milk Cheddar cheese, N. Y. (Cornell)
Exp. Sta. Ex. Bul. 18, 1917.
[102] Curd was spilled but practically all recovered.
[103] Suzuki, S. K., _et al._, Production of fatty acids and
esters in Cheddar cheese, Wis. Exp. Sta. Research Bul.
11.
[104] Babcock, S. M., _et al._, Cheese ripening as
influenced by sugar, Wis. Exp. Sta. Rept. 1901, pages
162-167.
[105] Bosworth, A. W., and M. J. Prucha, Fermentation of
citric acid in milk, N. Y. (Geneva) Exp. Sta. Tech.
Bul. 14, 1910.
Van Slyke, L. L., and A. W. Bosworth, Condition of
casein and salts in milk, N. Y. (Geneva) Exp. Sta.
Tech. Bul. 39, 1914.
Van Slyke, L. L., and E. B. Hart, A study of some of
the salts formed by casein and paracasein with acids;
their relation to American Cheddar cheese, N. Y.
(Geneva) Exp. Sta. Bul. 214, 1902.
Van Slyke, L. L., and E. B. Hart, Some of the
relations of casein and paracasein to bases and acids
and their application to Cheddar cheese, N. Y.
(Geneva) Exp. Sta. Bul. 261, 1905.
Van Slyke, L. L., and O. B. Winter, Cheese ripening
investigations, N. Y. (Geneva) Exp. Sta. Tech. Bul.
33, 1914.
[106] Van Slyke, L. L., and E. B. Hart, The relation of
carbon dioxide to proteolysis in the ripening of
Cheddar cheese, N. Y. (Geneva) Exp. Sta. Bul. 231,
1903.
[107] Van Slyke, L. L., and E. B. Hart, Some of the
compounds present in American Cheddar cheese, N. Y.
(Geneva) Exp. Sta. Bul. 219, 1902.
[108] Van Slyke, L. L., _et al._, Action of rennin or
casein, N. Y. (Geneva) Exp. Sta. Tech. Bul. 31, 1913.
Van Slyke, L. L., _et al._, Cheese ripening
investigations; rennet enzyme as a factor in cheese
ripening, N. Y. (Geneva) Exp. Sta. Bul. 233, 1903.
[109] Bosworth, A. W., Studies relating to the chemistry of
milk and casein, N. Y. (Geneva) Exp. Sta. Tech. Bul.
37, 1914.
[110] Wis. Exp. Sta. Rept. 1898, Distribution of galactase
in milk from different sources, pages 87-97.
Wis. Exp. Sta. Rept. 1903, pages 195-197, 201-205,
222-223, Action of proteolytic ferments on milk.
[111] Wis. Exp. Sta. Rept. 1900, pages 102-122.
[112] Harding, H. A., and M. J. Prucha, The bacterial flora
of Cheddar cheese, N. Y. (Geneva) Exp. Sta. Tech. Bul.
8.
[113] Bacterium, Bacillus and Lactobacillus are preferred by
different authors as generic placing of the Bulgarian
sour milk species.
[114] Hastings, E. G., Alice C. Evans and E. B. Hart, The
bacteriology of Cheddar cheese, Wis. Exp. Sta. Bul.
150, pages 1-52, 1912.
[115] Harding, H. A., The rôle of the lactic acid bacteria
in the manufacture and in the early stages of ripening
of Cheddar cheese, N. Y. (Geneva) Exp. Sta. Bul. 237,
1903.
[116] Heinemann, P. G., The kinds of lactic acid produced by
lactic acid bacteria, Jour. Biol. Chem., Vol. 2, pages
603-608.
[117] Hastings, E. G., _et al._, The bacteriology of Cheddar
cheese, U. S. Dept. Agr. Bur. An. Ind. Bul. 150, 1912.
[118] Van Slyke, L. L., and E. B. Hart, Conditions affecting
chemical changes in cheese ripening, N. Y. (Geneva)
Exp. Sta. Bul. 236, 1903.
[119] Van Slyke, L. L., _et al._, Cheese ripening at low
temperatures, N. Y. (Geneva) Exp. Sta. Bul. 234, 1903.
[120] Van Slyke, L. L., _et al._, Cheese ripening at low
temperatures, N. Y. (Geneva) Exp. Sta. Bul. 234, 1903.
[121] Doane, C. F., Methods and results of paraffining
cheese, U. S. Dept. Agr. Bur. An. Ind. Circ. 181,
pages 1-16, 1911.
[122] Doane, C. F., and E. E. Eldredge, The use of Bacillus
Bulgaricus in starters for making Swiss or Emmenthal
cheese, Dept. of Agr. Bur. An. Ind. Bul. 148, 1915.
[123] N. Y. Produce Rev. and Am. Creamery, Vol. 37, no. 25,
page 1112, Starter for Swiss cheese.
[124] Clark, W. M., On the formation of "eyes" in Emmenthal
cheese, Jour. Dairy Sci. 1 (1917), no. 2, pages
91-113.
Among important studies of Swiss cheese ripening are
the following: Freudenreich, E. v., and Orla Jensen,
Ueber die in Emmentalerkäse stattfindende
Proprionsäuregärung, Centralb. f. Bakt. etc. 2 Abt.
17, page 529.
Jensen, Orla, Biologische Studien über den
Käsereifungs-prozess unter spezieller Berucksichtigung
der flüchtigen Fettsäuren, Centralb. f. Bakt. etc. 2
Abt. 13 (1904), page 161.
Eldredge, E. E., and L. A. Rogers, The bacteriology of
cheese of the Emmenthal type, Centralb. f. Bakt. 2
Abt. 40 (1914), no. 1/8, pages 5-21.
[125] Gorini, C., Studi sulla fabricatione razionale del
fromaggi Grana, Boll. uff. del Ministero Agr. Ind. e
Comm. Anno X, serie C, Fasc. 10, pages 1-7, Roma,
1911.
Gorini, C., On the distribution of bacteria in Grana
cheese, Centralb. f. Bakt. etc. 2 Abt. 12 (1904),
pages 78-81.
Fascetti, G., The technological chemistry of the
manufacture of Grana cheese in Reggio, Staz. Sper.
Agr. Ital. 47 (1914), no. 8, pages 541-568.
[126] Cornalba, G., Caciocavallo in Lombardy, L'Industria
del Latte 3, page 105, Abs. in Jahresb. f. Tierchemie
36 (1906), page 250.
[127] Babcock, S. M., Albumin cheese, Wis. Exp. Sta. Rept.
12 (1895), page 134.
[128] Doane, C. F., Whey butter, U. S. Dept. Agr. Bur. An.
Ind. Circ. 161, pages 1-7, 1910.
Sammis, J. L., Making whey butter at Cheddar cheese
factories, Wis. Exp. Sta. Bul. 246, 1915.
Ellenberrger, H. B., and M. R. Tolstrup, Skimming whey
at Vermont cheese factories, Vt. Dept. Agr. Bul. 26,
1916.
[129] Farrington, E. H., and G. J. Davis, The disposal of
creamery sewage, Wis. Exp. Sta. Bul. 245, 1915.
[130] Dotterrer, W. D., and R. S. Breed, Why and how
pasteurize dairy by-products, N. Y. (Geneva) Exp. Sta.
Bul. 412, 1915.
[131] Harding, H. A., and G. A. Smith, Control of rust spots
in cheese, N. Y. (Geneva) Exp. Sta. Bul. 225, 1902.
[132] Elliott, W. J., Creameries and cheese factories, Mont.
Exp. Sta. Bul. 53, 1904.
Farrington, E. H., and E. H. Benkendorf, Origination
and construction of cheese factories and creameries,
Wis. Exp. Sta. Bul. 244, 1915.
[133] From N. Y. price current.
[134] Hart, E. B., A simple test for casein in milk and its
relation to the dairy industry, Wis. Exp. Sta. Bul.
156, pages 1-22, 1907.
[135] Sammis, J. L., The moisture test in the cheese
factory, Wis. Exp. Sta. Circ. 81, 1917.
Troy, H. C., A cheese moisture test, N. Y. (Cornell)
Exp. Sta. Ext. Bul. 17, 1917.
[136] Sammis, J. L., Correct payment for cheese factory milk
by the Babcock test, Wis. Exp. Sta. Bul. 276, 1917.
[137] Dairy Laws of Wisconsin, 1916, section 4607a.
[138] Sammis, J. L., The improved system of selling cheese,
Hoard's Dairyman 52 (1916), 15, pages 5, 11-12.
Hibbard, B. H., and A. Hobson, Markets and prices of
Wisconsin cheese, Wis. Exp. Sta. Bul. 251, pages 1-56,
1915.
[139] Hibbard, B. H., and Asher Hobson, Markets and prices
of Wisconsin cheese, Wis. Exp. Sta. Bul. 251, 1915.
[140] N. Y. Agricultural Laws, Sect. 3, paragraphs 48 and
49.
[141] Langworthy, C. F., and C. L. Hunt, Cheese and its
economical uses in the diet, U. S. Dept. Agr. Farmers'
Bul. 487, 1912.
[142] See also, Reich, R., Cheese as a food and its judgment
from standpoint of the food chemist, Arch. f. Hyg. 80
(1913), no. 1/6, pages 169-195.
[143] This calculation was added by the authors.
[144] Varietal name added by authors.
[145] Doane, C. F., and H. W. Lawson, Varieties of cheese,
U. S. Dept. Agr. Bur. An. Ind. Bul. 146.
[146] U. S. Dept. Agr. Bur. An. Ind., Dairy Div. A. I. 21,
1917.
[147] Doane, C. F., _et al._, The digestibility of cheese,
U. S. Dept. Agr. Bur. An. Ind. Circ. 166, pages 1-21,
1911.
[148] Langworthy and Hunt, _loc. cit._
[149] U. S. Dept. Agr. Farmers' Bul. 487, page 38.
[150] Levin, W., Cheese poisoning--a toxicogenic bacillus
isolated from cheese, Jour. Lab. Clin. Med. 2 (1917),
page 761.
[151] Thom, C., Camembert cheese problems in the United
States, U. S. Dept. Agr. Bur. An. Ind. Bul. 115.
[152] Langworthy and Hunt, _loc. cit._
[153] Langworthy and Hunt, _loc. cit._
[154] U.S. Dept. of Agr. Bur. An. Ind. A. I. 18.
INDEX
Acetic acid in cheese, 247.
Acid cocci, 19.
Acid fermentation, 17.
Acid organisms, 41.
Acid peptonizing organisms, 41.
Acidity,
in cheese and curd, 57, 58, 59.
and color, 67.
and rennet action, 66.
and ripening, 255.
and separation of whey, 66.
and texture, 67.
control of, 64.
in milk, 60.
testing, 60, 61.
Acidy cheese, 66.
Acme curd rake, 196.
Albumin, 10.
Albumin cheese, 295.
Alcohols in cheese, 248.
Alkaline bacteria, 20.
Appetitost, 114.
Ash of milk, 11.
Ayers, S. H. (Thom and), 21.
Babcock, S. M., 201, 237, 248, 295.
Babcock test, 327-332.
Bacillus botulinus, 370.
bulgaricus = Bacterium bulgaricum, 18, 279.
enteritidis, 370.
subtilis, 20.
Bäckstein cheese, 164.
Bacteria, 14.
alkali-producing, 20.
control of, 25.
from the air, 23.
from the cow, 23.
from the milker, 24.
from the utensils, 24.
groups of, in milk, 15.
in Cheddar ripening, 252-254.
inert type, 20.
influence on yield of Cheddar, 227.
peptonizing, 20.
sources in milk, 22.
Bacterium bulgaricum, 18, 19.
aerogenes, 18.
casei, 253.
coli-communis, 18, 252.
guntheri, 41.
lactis acidi, 18, 41, 252, 254.
lactis aerogenes, 252.
liquefaciens, 20.
prodigiosus, 20.
Baer, U. S., and W. L. Carlyle, 12.
Baker's cheese, 105.
Bang, Ivar, 39.
Bang's theory of casein, 37.
Barite, baryta, 159.
Barnard curd mill, 208.
Benson, Miles, 163.
Bergey, D. H., 16.
Besana, C., 29.
Block Swiss, 285.
Blue label, 109.
Blue-veined cheeses, 150.
Board of Health lactometer, 336.
Boards of Trade (Cheese), 349, 350.
Boekhout, J. W. J., and J. J. Ott de Vries, 174.
Bondon cheese, 94.
Bosworth, Alfred W., 37-38, 40, 126, 251.
Bosworth, A. W., and M. J. Prucha, 249.
Bosworth, A. W., and L. L. Van Slyke, 40.
Bosworth's theory of casein, 37.
Branding cheese, 360.
Breeds of cows, milk from, 6.
Brick cheese, 86, 136, 164 to 169, 358.
making, 165.
qualities, 167.
ripening, 167.
score-card, 169.
yield, 169.
Brie,
American, 134-136.
French, 117, 131, 132.
Brindse, Brinse cheese, 110.
Bushnell, L. D., and W. R. Wright, 44.
Buttermilk cheese, 93.
Butyric acid in Cheddar cheese, 248.
Butyric organisms, 21.
Buying milk, 343.
Caciocavallo cheese, 293.
California Jack cheese, 233.
Calorimeter values, 364.
Camembert cheese, 86, 111, 117 to 131, 137.
acidity in, 122.
bacteria in, 127.
composition, 128.
described, 117.
domestic, 360.
factory, 129.
group, 117.
lot-card, 124, 125.
making, 118-122.
ripening, 123.
Caproic acid in cheese, 136.
Carrés affinés, 114.
Casein, defined chemically, 33.
acted on by acid, 33.
in cheese ripening, 249.
in milk and cheese, 9.
Robertson's theory, 34.
test (Hart), 334.
Caseinogen, 35.
Catalase, 11.
Chapais, J. C., 137.
Cheddar cheese, 79, 86, 173, 184 to 275, 358, 368.
acidity test for, 190.
acidy, 266, 270.
American, 230.
body in, 271, 273.
boxes for, 264.
calorimeter studies of, 368.
cheddaring curd for, 204-207.
color in, 270.
composition of, 223.
cooking curd for, 195-200.
corky, 199.
cutting curd for, 193.
defects in, 265.
drawing whey, 200.
dressing, 216.
dry body in, 267.
English, 173.
feedy flavors in, 265.
finish in, 271.
firming curd for, 201-204.
flavor of, 221.
food value of, 362-365.
fruity flavors in, 266.
gas in curd for, 219.
gas in milk for, 217, 219, 269.
gassy, 268.
hooping curd for, 212.
hot-iron test for, 201, 208.
judging, 271.
losses in, 262, 263.
lot-card for, 184, 187.
matting, 204.
milk for, 186.
milling, 207.
moisture content of, 228, 258.
mottled, 221, 270.
packing curd for, 202.
paraffining, 263.
pin-holes in, 189.
pressing, 213.
quality in, 221, 272-273.
ripening milk for, 189 to 192.
ripening of, 247 to 263.
salting curd for, 211.
score-card for, 271, 273, 275.
seamy color in, 214, 221.
setting, 192.
shipping, 264.
starter for, 190, 191.
sweet flavor in, 266.
texture of, 267.
variations of process, 229.
yield, 224, 225.
Cheese, and health, 369.
and meals, 367.
and price of, 373.
boxes, 357.
canned, 372.
care in home, 372.
choice of, 370-371.
classification of, 81-85.
color, 56.
composition-table, 86, 364.
definition of, 1.
digestibility of, 368.
fondue, 375.
food value of, 362-367.
fuel value of, 365.
history of, 4.
in dietaries, 370-374.
in the household, 361-381,
knife, 205.
names, 81.
poisoning, 370.
price, 323, 357.
problems, 3.
processed, 84.
ripening (_see varietal descriptions_).
roast, 380.
salad, 378, 379.
sandwich, 371, 378.
sauce, 374, 381.
soufflé, 376.
total consumption of, 362.
trier, 272.
varieties, 3.
with sour-milk flavor, 89.
yield basis for buying milk, 343.
Cheese-making,
an art, 2.
a science, 3.
Chemistry of rennet action, 33-40.
Cheshire, 184.
Clabber cheese, 90.
Clark, W. M., 284.
Classification of cheese, 81 to 85.
Club cheese, 85, 231.
Cold-storage, 356, 361.
Colon-aërogenes group, 18.
Color, 56.
Colostrum, 18.
Commercial starter, 43.
Composition of Brick, 169.
Camembert, 128.
Cheddar, 223.
Cottage, 92.
Cream, 108.
Limburger, 147.
Neufchâtel, 105, 107.
Roquefort, 151.
Swiss, 287.
Conn, H. W., 16, 23, 152.
Connecticut (Storrs) Exp. Sta. Rept., 7, 16.
Constituents of milk, 7.
Cooking curd, 77.
for Cheddar, 195.
for Swiss, 281.
Coöperative organizations, 309.
Cornalba, G., 293.
Cottage cheese, 2, 86, 368, 379-381.
discussed, 90-93.
Coulommiers cheese, 111, 117, 131, 132.
Cow-brand cheese, 109.
Cream cheese, 108.
Curd, 9.
breaking, 75.
chemistry of, 33 to 40.
cooking of, 77.
cutting, 75.
draining, 79.
fork, 210.
knives, 77 (Fig. 11), 194, 195.
Curdling period, 74.
Curd-making, 55.
factors in, 55.
Curd mills, 207 to 209.
Curd pail, 213.
Curd rakes, 196.
Curd scoop, 213.
Curd sink, 204.
Curd test, 26.
Currie, James N., 149, 150, 155, 156.
Cutting, W. B., 159.
Cutting curd, 75-77.
for Brick, 165.
for Cheddar, 193-195.
for Edam, 175.
for Isigny, 135.
for Limburger, 141.
for Roquefort, 154.
for Swiss, 280-281.
Dahlberg, Arnold O., 98.
Daisies (cheese), 230.
Danish cheese, 173.
Davis, B. J. (and L. A. Rogers), 16.
Dean, H. H., 163.
Decker, John W., 217.
Derbyshire, 184.
Diastase, 11.
Digestibility of cheese, 367.
Diseased cows, effect on milk, 13.
Doane, C. F., 64, 263, 296.
Doane, C. F., and E. E. Eldredge, 279.
Doane, C. F., and H. W. Lawson, 169, 365.
Dotterrer, W. D., and R. S. Breed, 301.
Dox, Arthur W., 126, 150.
Draining, 79.
Camembert, 121-122.
Cheddar, 195-206.
Cottage, 91.
Limburger, 142.
Neufchâtel, 97.
Roquefort, 154.
Swiss, 280-282.
Draining cloths,
for Jack cheese, 235.
for Neufchâtel, 97.
for Swiss, 282.
Draining rack for Neufchâtel, 97.
Dressing Cheddar, 216.
Dry body, 267.
Duclaux, E., 39, 33-40.
Duclaux's theory of casein, 36.
Dutch cheeses, 173.
Dutton, G. C., 184.
Eagle brand, 109.
Eckles, C. H., and Otto Rahn, 112.
Eckles, C. H., and R. H. Shaw, 7.
Edam cheese, 173, 174 to 180, 366.
Eldredge, E. E., and L. A. Rogers, 284.
Ellenberger, H. B., and M. R. Tolstrup, 296.
Elliott, W. J., 310.
Emmenthal or Emmenthaler, 276
English dairy cheese, 238.
Enzymes,
in cheese-ripening, 250.
in milk, 11.
Equipment list for Cheddar factory, 307.
Esten, W. M., 41.
Esten, W. M., and C. J. Mason, 16, 129.
Esters in Cheddar cheese, 248, 254.
Export Cheddar, 230.
Exportation of cheese, 321.
Factory, 297-309.
arrangement, 302-306.
boiler-room in, 301.
building, 299.
cleanliness in, 307.
coöperative, 308.
curing-rooms, 300.
drainage, 298.
equipment list, 307.
heating, 300.
location of, 298, 299.
organization, 308-309.
proprietary, 308.
supplies, list for, 307.
system, 313, 320.
ventilation of, 300.
water in, 298.
Farm cheese, 133.
Farrington, E. H., and G. H. Benkendorf, 310.
Farrington, E. H., and G. J. Davis, 298.
Farrington, Harvey, 314.
Farrington's test, 62.
Fascetti, G., 288.
Fat-basis for buying milk, 344.
Fat and casein ratio, 224, 226.
Fat and cheese yield, 225, 226.
Fat and water content, 86.
Fat in cheese-ripening, 86.
Fat in milk, 8.
Fat loss, 226-227.
plus two method, 345.
Fat test, 327-334.
Feeds, 11.
Fermentation, 15.
Fermentation test, 26.
Ferments, 15, 29.
Filled cheese, 315, 361.
Fisk, Walter W., 68, 89, 228.
"Flats," 230.
Flavor of cheese, 368, 371.
Flavor of feeds, 11.
Fleischmann, W., 152.
Food value of cheese, 362-367.
Forbes, E. B., and M. H. Keith, 9, 33 to 40.
Formic acid in Cheddar, 248.
Frandsen, J. H., 23, 89.
Frandsen, J. H., and T. Thorsen, 89.
Fraser, W. J., 23.
Fraser hoop, 212.
Frestadius, A., 159.
Freudenreich, E. von, and Orla Jensen, 284.
Full skim Cheddar, 242.
Galactase, 11.
Gang press, 214.
Gases in cheese-ripening, 249.
Gassy curd, 146, 220.
Gassy milk, 219.
Geographical distribution of cheese factories, 315.
Germicidal effect of milk, 22.
Gervais cheese, 109.
Getman, Louis, 139.
Gex cheese, 164.
Glaesler (Swiss), 286.
Glymol, 334.
Goat cheese, 109.
Gorgonzola cheese, 158 to 161.
Gorini, Constantine, 288.
Gosselin curd mill, 208.
Gouda cheese, 173, 180 to 183.
Gournay cheese, 114.
Grana cheese, 288.
Granular curd cheese, 232.
"Green" cheese, 247.
Gruyère, 276.
Guthrie, E. S., and W. W. Fisk, 44.
Haecker, T. L., 180.
Half-skim Cheddar, 243.
Hall, W. W., 187.
Halliburton, 35.
Hammarsten, Olof, 39, 33-40.
Hammarsten's theory of rennet action, 35.
Hand cheese, 112.
Hard cheese, 172.
Harding, H. A., 23, 254.
Harding, H. A., and M. J. Prucha, 252.
Harding, H. A., J. K. Wilson, and G. A. Smith, 25.
Harding, H. A., and G. A. Smith, 306.
Harris curd mill, 209.
Hart, E. B., 38, 40, 91, 201, 249, 253, 255, 256, 334.
Hart casein test, 334.
Harz cheese, 112.
Hastings, E. G., 21, 44, 237.
Hastings, E. G., and Alice C. Evans, 60.
Hastings, E. G., Alice C. Evans, and E. B. Hart, 253, 255.
Hayward, H., 180.
Heat in cheese-making, 77-78, 87, 91, 195, 281.
Heinemann, P. G., 254.
Hibbard, B. H., and A. Hobson, 349, 358-359.
History of cheese-making, 4, 311.
Hoops, for Camembert, 121.
for Cheddar, 212.
for Roquefort, 154.
for Swiss, 278.
Hosl, J., 39.
Hot-iron test, 201.
Household, cheese in, 362-381.
Hunziker, O. F., 22.
Hydrogen in Cheddar, 254.
Importation of cheese, 321.
Inert bacteria, 20.
Iowa Exp. Sta. Bull., 310.
d'Isigny cheese, 132, 134-137.
Italian cheeses, 288-291.
Jack cheese, 184, 233-236.
Jensen, Orla, 284.
Junker curd mill, 209.
Kascoval cheese, 164.
Kiernan, Mrs. E. E., 113.
Kikkoji, 36, 39.
King, F. H., and E. H. Farrington, 12.
Kosher cheese, 136.
Lactic starter, 41-54.
Lactometer, 335.
Board of Health type, 336.
Quevenne type, 335.
Lactose (_see_ Milk-sugar), 10.
Langworthy, C. F., and C. L. Hunt, 363, 372.
Larsen, C., and W. White, 44.
Lauder, A., and A. Cunningham, 22.
Laws about cheese, 359-361.
Laws about milk, 347.
Leicestershire, 184.
Levin, W., 370.
Leyden cheese, 238.
License for cheese-maker, 361.
Liederkrauz cheese, 134, 138.
Ligeon, X., 170.
Limburger, 86, 136, 139 to 147, 358, 371.
factory, 139-140.
making process, 140-143.
qualities, 145.
ripening, 143-145.
wrapping, 145.
yield of, 147.
Lindet, L., 38, 39.
Lipase, 11.
Livarot cheese, 135.
Loevenhart, A. S., 36, 39.
Long-horn (Cheddar) cheese, 230.
Lot-card, for Camembert, 124-125.
for Cheddar, 184, 187.
for starter, 53.
Macaroni and cheese, 377.
Maine Exp. Sta. Rept., 7.
Malakoff cheese, 94, 114.
Manns, A. G., 7.
Manns test, 231.
Manufacturer's brand, 360-361.
Marketing, 343-361.
laws concerning, 360.
Marre, E., 151.
Marschall test, 62.
Marshall, C. E., 189, 217.
Marty, G., 165.
Matheson, K. J., F. R. Cammack, 100.
Matheson, K. J., C. Thom, and J. N. Currie, 94.
Matting, 204.
Mayo, N. F., and C. G. Elling, 289.
Mazé, P., 116.
McAdam, Robert, 314.
McNaughton, Janet, 132.
McPherson curd agitator, 196.
Mercantile exchanges, 351.
Michels, John, 89.
Michigan Agr. Law, 13.
Milk, acid fermentation of, 17.
acidity in, 60.
albumin, 10.
ash, 11.
bacteria in, 21.
bacterial contamination of, 21.
buying, 343.
casein in, 9, 224.
clean, 22.
colostrum in, 13.
composition of, 5, 6, 56, 222.
constituents, 7.
defined, 5.
enzymes in, 11.
fat in, 8, 224.
flavors in, 11.
from diseased cows, 13.
germicidal property, 22.
lactose in, 10.
moisture in, 8.
odors in, 12.
paying for, 343.
quality in, 5.
sugar (lactose), 10.
variation in composition, 6.
Milking machines, 25.
Milk-sugar, 10.
Moisture and acidity, 70.
Moisture control, 68, 69.
Moisture limits in cheese, 358.
Moisture test (Troy's), 337-342.
Molding machines for Neufchâtel, 98.
Molding Neufchâtel, 104.
Molds,
in Cheddar, 271.
in milk, 21.
Monrad, J. H., 112, 114, 180.
Moore, V. A., and A. R. Ward, 217.
Morrow, G. A., and A. G. Manns, 7.
Mottled Cheddar, 221, 270.
Mucors, 93.
Münster, 147, 148, 366.
Mysost, 293, 295.
Natural starter, 43.
Neufchâtel, 80, 85, 86, 89, 371.
American, 95.
domestic, 95, 106.
factory, 95.
group discussed, 94 to 109.
packages, 98.
ripened form, 114-116, 117.
yield, 107.
New Jersey Exp. Sta. Rept., 7.
New York (Geneva) Exp. Sta. Rept., 7, 8, 174.
New York Mercantile Exchange, 351-356.
New York Price Current, 315, 351.
New York Produce Review, 165, 233, 280.
New York State Department of Agriculture, 13.
Niszler (Swiss) cheese, 286.
Nut cheese, 109.
Odors absorbed by milk, 12.
Oidium (Oospora) lactis, 113, 116, 131, 136, 163.
Oka cheese, 169.
Olimento cheese, 109.
Olive cheese, 109.
Olson, G. A., 74.
Ontario Agricultural College Bulletins, 7, 228.
Over-ripe milk, 218.
Pails, 24, 25.
Paracasein, 35, 250.
Paraffining Cheddar, 263.
Parmesan cheese, 2, 80, 86, 173, 288-291.
Pasteurization, 11, 26, 45, 229, 396.
Pasteurized Cheddar, 229.
Pasty body, 270.
Paying for milk, 343-346.
Penicillium brevicaule, 129.
camemberti, 116, 126, 127, 131.
camemberti var. rogeri, 116.
candidum, 116.
roqueforti, 155, 156, 159, 163.
Pennsylvania pot cheese, 113.
Pepsin, 30, 33.
Peptonizing bacteria, 20.
Percival, J., and G. Heather Mason, 163.
Perishable varieties, 356.
Peroxidase, 11.
Petit Carré, 94, 114.
Petite Suisse, 94, 114.
Petits Bondons, 114.
Petry, E., 36, 39.
Philadelphia cream, 109, 360.
Picnic cheese, 230.
Pimiento cheese, 85, 101.
Pimientos in Cheddar, 238.
Pim-olive cheese, 109.
Pineapple cheese, 184, 238.
Pohl curd mill, 208.
Poisoning by cheese, 370.
Pont l'Eveque cheese, 135.
Pooling method, 345.
Port du Salut cheese, 136, 169 to 171.
Pot cheese, 113.
Pouriau, A. F., 82, 114.
Press cloths, 212.
Presses, 214, 215.
Prices,
distribution of, 357-359.
yearly average of, 323.
Primost, 295.
Processed cheese, 84.
Propionic acid in cheese, 247, 248.
Provolono, 294.
Prucha, M. J., and H. M. Weeter, 23.
Ptyalin, 30.
Publow, C. A., 60.
Publow's test, 62.
Pure culture starter, 43.
Quality,
in Cheddar, 272-273.
in Edam, 180.
in Limburger, 145.
in milk, 6.
in Swiss, 286.
Quevenne lactometer, 335.
Rabbit cheese, 372.
Raffiné cheese, 137, 138.
Recipes for cooking cheese, 375-381.
Reductase, 11.
Regianito cheese, 292.
Reich, R., 363.
Rennet, 9, 30, 312.
action, 33 to 40.
action, chemistry of, 33
action delayed by, 73.
adding, 72.
amount to use, 72.
extract, 31, 279.
for Camembert, 121.
for Cheddar, 192.
for Limburger, 141.
for Neufchâtel, 100.
for Roquefort, 153.
for Swiss, 279.
in ripening Cheddar, 250.
strength of, 72.
temperature of using, 71.
test, 62.
Rennin, 30.
Rice and cheese, 377.
Ricotte, 11, 295.
Robbiola, 117.
Robertson, T. Brailsford, 38.
Robertson's theory of casein, 34.
Roger, Georges, 116.
Rogers, L. A., 16.
Rogers, L. A., and B. J. Davis, 16.
Roquefort cheese, 2, 86, 150, 158, 368, 369, 371.
acidity for, 153.
caves for, 151.
composition of, 151.
curdling for, 153.
cutting curd for, 154.
draining, 154.
from cow's milk, 152.
milk for, 153.
mold for, 154.
ripening of, 156-157.
salting, 155.
setting, 153.
temperature, 153.
Ruddick, J. A., and G. H. Baur, 26.
Russell, H. L., 189, 217.
Rusty spots, 74, 306.
Sage cheese, 239-241.
Salt in Cheddar ripening, 259.
Salting,
Camembert, 122.
Cheddar, 211.
Limburger, 142.
Neufchâtel, 102.
Roquefort, 155.
Swiss, 283.
Sammis, J. L., 95, 228, 296, 337, 347, 349.
Sammis, J. L., and A. T. Bruhn, 11, 41, 57, 229.
Sammis, J. L., S. K. Suzuki and F. W. Laabs, 33.
Sammis' method, 229.
Sap sago, 294.
Schenk, C., 165.
Schmidt-Nielson, S., 36, 39.
Schmierkäse, 90.
Schroeder, E. C., 99.
Schweitzer cheese, 276.
Score-card,
for Brick, 169.
for Cheddar, 271.
for Limburger, 146.
for starter, 51.
for Swiss, 287.
Sediment test, 27, 28.
Semi-hard cheeses, 149-171.
Setting, 71.
Shaw, R. H. (and C. H. Eckles), 7.
Sheep's milk, 151, 152.
Sheep's milk cheese, 150.
Sheldon, J. P., 161.
Shot-gun cans, 97.
Size factor in ripening, 263.
Skim cheese, 89, 361, 366.
bacteria, 134-147.
Cheddar, 241-246.
Neufchâtel, 105, 107.
ripened by molds, 111.
Soft cheeses, 82-83, 86.
Solids not fat, 335-337.
Speed knife, 217.
Spiro, K., 36, 39.
Square cream, 109.
Standards, 359.
Starter, 42.
amount to use, 52.
care of milk for, 47.
commercial, 43.
containers for, 45.
for Brick, 165.
for Camembert, 121.
for Cheddar, 189.
for Neufchâtel, 99.
for Roquefort, 153.
for Swiss, 279.
handling, 42-50.
lot-card for, 53.
"mother," 47
natural, 42.
pasteurization of, 45.
propagation of, 46-48.
qualities of, 50.
score-card for, 51.
Startoline, 47.
State brands, 360.
Stevenson, C., 29.
Stilton cheese, 161-163.
Stirred curd cheese, 232.
Stocking, W. A., Jr., 22, 23, 25.
Storage of cheese, 103.
Streptococcus lacticus, 41.
Streptothrix-actinomyces group, 21.
Succinic acid, 254.
Suzuki, S. K., 247.
Sweet curd cheese, 236.
Swiss cheese, 80, 86, 173, 276-288, 358, 366, 368, 371.
block, 278.
breaking, 281.
composition, 287.
curing, 283.
cutting, 280.
drum, 278.
eyes in, 283-285.
factories, 276-278.
making process, 280-283.
pressing, 282.
quality in, 286.
rennet for, 279.
salting, 283.
score-card for, 287.
starter for, 279.
testing, Chapter XIX, 327.
Swiss harp, 278.
Tests,
acid, 60, 61.
Babcock, 327-334.
casein, 334.
curd, 26.
fat, 327.
fermentation, 26.
Hart, 334.
hot-iron, 201.
lactometer, 335-337.
moisture in cheese, 337-342.
rennet, 62.
sediment, 27, 28.
solids not fat, 335-337.
Troy's moisture, 337-342.
Thom, C., 117, 154, 155, 158, 372.
Thom, C., and S. H. Ayers, 21.
Thom, C., and J. N. Currie, 156.
Thom, C., J. N. Currie, and K. J. Matheson, 116, 152.
Thom, C., and K. J. Matheson, 149.
Tinfoil wrapping, 145.
Todd, A., and E. C. V. Cornish, 29.
Tolstrup, R. M., 91.
Trappist, 169.
Trier, 272.
Troy, H. C., 337.
Trypsin, 30.
Twins, 230.
Tyrein, 35.
U. S. Census Report, quoted, 317, 318 to 322.
U. S. Dept. Agr. Yearbooks, quoted, 326.
U. S. Treasury Dept. Hygienic Laboratory Bulletin, 22.
Utensils, 24.
Valerianic acid in cheese, 136.
Van Dam, W., 29, 36, 39.
Van Eyck Machine Co., 98.
Van Herwerden, M., 36, 39.
Van Slyke, L. L., 8, 223, 224, 225, 251, 257, 262.
Van Slyke, L. L., and A. W. Bosworth, 9, 36, 39, 40, 249.
Van Slyke, L. L., and D. D. Van Slyke, 33.
Van Slyke, L. L., and E. B. Hart, 38, 40, 91, 201, 249, 256.
Van Slyke, L. L., and C. A. Publow, 310.
Van Slyke, L. L., and O. B. Winter, 249.
Vat, 190.
Vermont Exp. Sta. Rept., 7.
Victor curd mill, 208.
Ward, A. R., 217.
Washed curd process, 236.
Water in milk, 8.
Welsh rabbit, 377.
Wensleydale, 184.
Whey, 222.
Whey butter, 295.
Whey cheese, 85, 295.
Whey siphon, 202.
Whey strainer, 202, 203.
Whey tank, 301, 303.
White cheese, 109.
Williams, Jesse, 313.
Wilson hoop, 212.
Wing, Lois W., 25.
Wisconsin Agr. Law, 13, 347.
Wisconsin curd test, 26.
Wisconsin pasteurized Cheddar, 229.
Wisconsin Sta. Bul., quoted, 7, 8, 10, 26, 251, 253.
Working of curd, 102, 135.
Wuethrich, F., 165.
Yeasts, 21.
Yield of, Brick, 169.
Camembert, 130.
Cheddar, 226.
Limburger, 146.
Neufchâtel (whole milk), 107.
Swiss, 287.
Young America, 230.
Zumkehr, P. 139.
* * * * *
The following pages contain advertisements of a
few of the Macmillan books on kindred subjects
THE RURAL TEXT-BOOK SERIES
EDITED BY L. H. BAILEY
Butter
BY E. S. GUTHRIE
Professor in the Dairy Department, New York State College of
Agriculture, Cornell University
A practical discussion of the general characteristics of butter, and of
all of the problems connected with its manufacture and marketing,
together with a brief history of the product. Among the topics
considered are the history of butter; composition and food value of
butter; cleansing and care of dairy utensils; care of milk and cream;
cream separation; grading milk and cream and neutralizing acidity;
pasteurization; cream ripening; churning, washing, salting and packing
butter; flavors of butter; storage of butter; marketing; whey butter,
renovated and ladled butter; margarine, and testing.
THE MACMILLAN COMPANY
Publishers 64-66 Fifth Avenue New York
A Manual of Milk Products
BY W. A. STOCKING, JR.
Professor of Dairy Bacteriology in the New York State College of
Agriculture at Cornell University
_$2.00_
This is the most recent addition to the Rural Manual Series under the
editorship of L. H. Bailey. The work is intended to serve as a reference
book covering the entire subject of milk and its products. There are
chapters on The Chemical Composition of Milk, The Factors Which
Influence Its Composition, Physical Properties, The Various Tests Used
in the Study of Milk, The Production and Handling of Milk, Butter
Making, The Cream Supply, Butter Making on the Farm, Cheese Making, and
the Bacteriology of Dairy Products.
THE MACMILLAN COMPANY
Publishers 64-66 Fifth Avenue New York
The Modern Milk Problem
BY J. SCOTT MACNUTT
Lecturer on Public Health Service in the Massachusetts Institute of
Technology
_With 16 plates and 22 illustrations. Cloth, 12mo, $2.00_
Notwithstanding the fact that the milk problem is constantly growing
more acute in many parts of the United States, no book has thus far
appeared treating, in a brief space, its main aspects and stressing the
practical and economic as well as the sanitary factors involved. The
present volume is designed to fill this obvious need by providing a
convenient survey of a perplexing subject--not merely for health
officials and milk inspectors, but also for dairy-men and city milk
dealers, agricultural authorities, legislators charged with the framing
of milk laws, inquiring consumers and members of organizations engaged
in efforts to secure better milk supplies, physicians, and all others
who are interested in the understanding and solution of the milk
problem. The entire work is essentially practical and valuable as a
constant reference.
THE MACMILLAN COMPANY
Publishers 64-66 Fifth Avenue New York
Cooperation: The Hope of the Consumer
BY EMERSON P. HARRIS
President of the Montclair Coöperative Society. With an Introduction by
JOHN GRAHAM BROOKS.
_Cloth, 12mo_
The author's purpose has been to discuss coöperative purchasing, to show
why it is desirable, to indicate the evils which it reforms, to present
the operation of a coöperative store and to consider the difficulties
which must be overcome.
The titles of the four parts into which this work is divided are as
follows: The Failure of Our Middlemanism, Reasons and the Remedy,
Practical Coöperation, Background and Outlook.
The Marketing of Farm Products
BY L. D. H. WELD
_$1.60_
This book aims to set forth the fundamental principles of market
distribution as applied to the marketing of agricultural products. It
begins by pointing out the place that marketing occupies in the general
field of economics, and by applying accepted economic principles to the
marketing process. It then explains the general organization and methods
of marketing, beginning with marketing at country points, and passes on
to a description of the methods and functions of the various classes of
wholesale dealers. After describing the factors affecting the cost of
marketing, illustrated by data concerning the marketing of certain
specific products, a number of special problems are treated, such as
price quotations, future trading, inspection and grading, public
markets, coöperative marketing, etc.
THE MACMILLAN COMPANY
Publishers 64-66 Fifth Avenue New York
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| Transcriber's note: |
| |
| The original text contains a large number of words which occur |
| in hyphenated and spaced forms with comparable frequency. Such |
| inconsistencies have been retained in this version. |
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