Chapter 31
Woman's Inst.i.tute Library of Cookery.
Vol. 2.
by Woman's Inst.i.tute of Domestic Arts and Sciences.
PREFACE
This volume, which is the second of the Woman's Inst.i.tute Library of Cookery, deals with such essentials of diet as the dairy products--milk, b.u.t.ter, and cheese--the protein food, eggs, and the energy-producing nutrients, vegetables.
In _Milk, b.u.t.ter, and Cheese_, Parts 1 and 2, are explained the place that milk occupies in the diet, its composition, grades, and the dishes for which it is used; the purchase, care, and use of b.u.t.ter and b.u.t.ter subst.i.tutes; and the characteristics, care, and varieties of both domestic and imported cheeses, as well as a number of excellent recipes for cheese dishes. A luncheon menu, in which a cheese dish is subst.i.tuted for meat, is of interest in this connection, for it shows the housewife, early in her studies, not only how to combine dishes to produce a balanced meal, but also how to make up a menu in which meat is not needed.
In _Eggs_ are discussed the nutritive value of eggs, the ways in which to select, preserve, cook, and serve them, and how to utilize left-over eggs. So many uses have eggs in the diet and so nouris.h.i.+ng is this food that too much attention cannot be paid to its preparation. In this lesson, also, is given a breakfast menu to afford practice in preparing several simple dishes usually served in this meal.
In _Vegetables_, Parts 1 and 2, every variety of vegetable is discussed as to food value, preparation, place in the meal, and proper methods of serving. With such a fund of knowledge, the housewife will be well equipped to give pleasing variety to her meals.
In addition to the instruction in these matters, there are a large number of ill.u.s.trations, which make clear the important details in every process employed and in many recipes show certain steps as well as the finished result. With such detailed information, it is our desire that as many of the recipes as possible be tried, for it is only through constant practice that the rules and principles of cookery will become thoroughly instilled in the mind. Nothing is of more value to the housewife than such a knowledge of food and its preparation, for, as every one knows, proper diet is the chief requisite of good health.
To be of the greatest a.s.sistance to the woman in the home is the purpose of these volumes--to relieve her household tasks of much of their drudgery and to help her come to a realization of the opportunity for good that is hers. In no better way can she create happiness and contentment in her home than by preparing appetizing, nutritious meals and serving them in the most attractive manner.
MILK, b.u.t.tER, AND CHEESE (PART 1)
MILK
MILK IN THE DIET
1. As is well understood, milk is the liquid that is secreted by the mammary glands of female mammals for the nourishment of their young. The word milk as it is commonly used, however, refers to _cow's milk,_ because such milk is employed to a greater extent as human food than the milk from any other animal. Cow's milk in its perfectly fresh raw state is a yellowish-white, opaque fluid, called _whole milk,_ and, as is well known, possesses a distinctly sweet taste and characteristic odor. When such milk is allowed to stand for some time without being disturbed, it separates into two distinct layers, an upper and a lower one. The upper layer, which is lighter than the lower one and occupies a smaller s.p.a.ce, consists largely of globules of fat and is called _cream;_ the lower layer, which is white or bluish-white in color and is composed of water, solids, and protein, is, when separated from the cream, called _skim milk._
2. As an article of diet, milk is very important, because its sole function in nature is to serve as food. It is required by the infant; it is needed in the diet of all growing children; and it is desirable in the preparation of dishes for both young and old.
Milk is used to such a great extent because it fills many of the requirements of an ideal food. It is generally liked, requires little or no time for preparation, agrees with the majority of persons when used properly, and contains substances that supply energy and build and repair tissue. Still, it does not contain these substances in such proportions as to make it an ideal or exclusive article of diet for adults, and it must often be modified to suit the needs of infants, because it is ideal for only the young of the species for which it is intended. Therefore, while milk is often called a perfect food, in reality it is perfect for only the calf. When it is desired for the feeding of a very young child, it must be changed to meet the requirements before it can be used with good results.
3. So important is milk as an article of food that, outside of the purely rural districts, producing the milk supply is a business of considerable importance. This is due to the fact that the purity of milk must be constantly safeguarded in order that clean, safe milk may be provided for the countless numbers that depend on it. In fact, milk undoubtedly bears a closer relation to public health than any other food. To produce an adequate amount of clean, safe, pure milk is one of the food problems of the city and country alike. In the city much of the difficulty is overcome by the ordinances that provide standards of composition and cleanliness, as well as inspection to insure them; but such ordinances are rarely provided for in villages and country districts.
When there is no law to prevent it, unclean milk is sometimes used in the manufacture of b.u.t.ter and cheese, but when this happens, great injustice, if not positive harm, is done to the consumers of these articles. Then, too, unless milk is carefully inspected, tubercular milk is liable to be used in the making of b.u.t.ter, and such a condition will cause the spreading of tuberculosis as readily as the use of the contaminated milk itself.
4. With its various products, milk helps to form a very large part of the dietary in most homes, but while nothing can take the place of this food and while it is high in food value, there seems to be a general tendency to think of it as an addition to the bill of fare, rather than as a possible subst.i.tute for more expensive food. For instance, milk is very often served as a beverage in a meal in which the quant.i.ty of meat or other protein foods is not reduced. From an economical standpoint, as well as from the point of view of the needs of the body, this is really extravagant, for milk is itself largely a protein food. The serving of a gla.s.s of milk or of a dish that contains generous quant.i.ties of milk offers the housewife an opportunity to cut down considerably the allowance of meat and eggs. Because of this fact and because milk and its products may be used to add nutritive value to a food, to give variety, and to improve flavor, they deserve considerable study on the part of the housewife.
5. Since milk may be used in such a variety of ways, it may be easily included in the dietary for the family. Being liquid in form, it may always be served without any preparation as a beverage or with other beverages, cereals, and fruits. It also has numerous other uses, being employed in the making of sauces for vegetables and meats, in the place of stock for soups, and as the liquid for bread, cakes, puddings, custards, and many frozen desserts. Because of its extensive use, every housewife not only should know how to buy milk and care for it, but should be familiar with its composition, so that she may determine whether or not it suits the needs of her family. In addition, she should know the effect of heat on milk and the various methods
COMPOSITION OF MILK
6. As milk is usually taken into the body in liquid form, the common tendency is to regard it as a beverage, rather than as an important source of nouris.h.i.+ng food material. However, a knowledge of its composition, as well as the fact that milk becomes a solid food in the stomach and must then be dissolved in the process of digestion, will serve to show that milk contains solids. That it possesses all the elements required to sustain life and promote health is proved by the fact that a child may live for months on milk alone and during this time increase in weight.
7. The solids contained in milk are proteins, fat, carbohydrate in the form of sugar, and mineral salts, besides which, of course, water occurs in large quant.i.ties. The sugar and fat of milk serve as fuel; the mineral salts are chiefly valuable for the growth of bones and teeth and for their effect on the liquids of the body; and the proteins, like the fat and sugar, serve as fuel, but they also make and repair the muscular tissues of the body.
In considering the food substances of milk, it will be well to note also that they vary according to the breed, feeding, and individual characteristics of the cow. Jerseys and Guernseys give milk rich in fat and total solids, and while Holstein cows give a greater quant.i.ty of milk, such milk has a smaller proportion of fat and total solids. As a rule, though, the composition of milk may be considered as approximately 3.3 per cent. protein, 4 per cent. fat, 5 per cent. carbohydrate, and.7 per cent. mineral matter, making a total of 13 per cent. This indicates the quant.i.ty of actual food material in milk, the remainder, or 87 per cent., being water.
8. PROTEIN IN MILK.--Because of the double usefulness of protein--to serve as fuel and to make and repair muscular tissue--this element is regarded as an important ingredient of milk. The protein in milk is called _casein_. The opaque whiteness of milk is largely due to the presence of this substance. As long as milk remains sweet, the lime salts it contains hold this casein in solution; but when it sours, the salts are made soluble and the casein thickens, or coagulates. In addition to casein, milk contains a small amount of protein in the form of _alb.u.min_. This substance, upon being heated, coagulates and causes the formation of the skin that is always found on the top of milk that has been heated. The skin thus formed contains everything that is found in milk, because, as it forms, casein is dried with it and sugar and fat, too, are caught and held there. It is the protein of milk and its characteristic coagulation that are made use of in the making of cheese.
In cooking, the protein of milk is probably more affected than any of the other substances, but the degree to which the digestion of milk is thus affected is not definitely known, this being a much disputed question.
9. FAT IN MILK.--The other substance in milk that serves as fuel, or to produce energy, is fat. It occurs in the form of tiny particles, each surrounded by a thin covering and suspended in the liquid. Such a mixture, which is called an _emulsion_, is the most easily digested form in which fat is found. The fat in milk varies more than the other food substances, it being sometimes as low as 2 per cent, and again as high as 6 per cent. However, the average of these two, or 4 per cent., is the usual amount found in most milk.
As has been mentioned, the fat globules of milk rise to the top because fat is lighter than water, so that when milk has been undisturbed for some time the top, which is known as _cream_, will be found to contain most of the fat. Because of the fat it contains, the cream is yellower in color than the milk underneath. If the cream is beaten, or churned, these fat particles will adhere in a ma.s.s, advantage of this fact being taken in the making of b.u.t.ter.
10. CARBOHYDRATE IN MILK.--The carbohydrate contained in milk is in the form of sugar called _lactose_. It is unlike other sugars in that it is not very sweet and does not disagree with most persons nor upset their digestion. For this reason, it is often given to children, invalids, and persons who have digestive disturbances. However, it is like other carbohydrates in that in solution it ferments. The result of the fermentation in this case is the production of _lactic acid_, which makes the milk sour. With the fat, lactose makes up the bulk of the energy-producing material of milk, and while this is important it is only secondary when compared to the tissue-building power of the protein and minerals. Besides being an important part of milk itself, lactose is a valuable by-product in the manufacture of cheese. After being taken from _whey_, which is the clear, straw-colored liquid that remains when the curd, or coagulated portion, is completely removed from the milk, the lactose is refined and sold in the form of a powder that is used for various kinds of infant and invalid feeding.
11. MINERAL MATTER IN MILK.--Considerable quant.i.ties of mineral salts, which are chiefly _lime_, _potash_, and _phosphates_, are found in milk.
As has already been pointed out, these are important in the building of bone and hard tissue in the body, but in addition they help to keep the fluids of the body in the right condition. Because of the work they do, these mineral salts are necessary in the building of the bodies of growing children, and are useful for repair and the regulation of the body processes in adults. In cheese, b.u.t.ter, and cream, which are the products of milk, less of the mineral salts are found in proportion to the quant.i.ty than in whole milk, skim milk, and whey.
12. WATER IN MILK.--The percentage of water in milk is much greater than that of all the other food substances combined, there being more than six times as much. While this quant.i.ty seems very large, it is an advantage, for milk provides nourishment to persons when they can take neither solid nor more condensed food. On the other hand, the water is a disadvantage, for it is responsible for the rapid spoiling of milk. This fact is clearly shown in the case of condensed milk, where the water is partly or completely evaporated, for milk of this kind keeps much longer without spoiling than either whole or skim milk.
PRODUCTS OBTAINED FROM MILK
13. Although milk is used extensively in its natural liquid form, considerable use is also made of the numerous products of milk, chief among which are cream, skim milk, b.u.t.termilk, sour milk, whey, b.u.t.ter, and cheese. In fact, all of these occupy such an important place in the dietary of the majority of homes that it is well for every housewife to understand their value. b.u.t.ter and cheese are discussed in detail later, so that at this time no attention need be given to them. The other products, however, are taken up now, with the intention of enabling the housewife to familiarize herself with their production, nature, and use.
14. CREAM.--As has been pointed out, the particles of fat that rise to the top of milk when it is allowed to remain undisturbed for some time form the product known as cream. Cream may be removed from the milk by skimming it off, or it may be separated from the milk by means of machinery especially designed for the purpose. The greater the proportion of fat in milk, the thicker, or "heavier," will be the cream.
Various grades of separated cream are placed on the market, the usual ones being those which contain 8, 12, 16, 20, and 40 per cent, of fat.
Thin cream, which includes the grades that have only a small percentage of fat, contains a larger quant.i.ty of milk than the others and is not so desirable for many purposes. Still, it is used to some extent, because it is cheaper and there are definite uses to which it can be put.
Medium-heavy cream is the kind to select when it is desired for _whipping_. This is a process that consists in beating the cream rapidly until a ma.s.s of tiny bubbles form and become stiff, very much as the white of egg does.
15. SKIM MILK.--After a part or all of the cream has been removed from whole milk, that which remains is called skim milk. While practically all of the fat is taken out when milk is skimmed, very little protein or sugar is removed. Therefore, skim milk is still a valuable food, it being used to a large extent for cheese making, for the manufacture of certain commercial foods, and for the feeding of animals. The housewife does not, as a rule, buy skim milk; indeed, in some localities the laws prevent its sale because it is considered an adulterated food. However, it is really a wholesome, valuable food that is cheaper than whole milk, and its use in the home should therefore be encouraged from an economical standpoint. Here it may be used in the preparation of many dishes, such as sauces, cakes, biscuits, m.u.f.fins, griddle cakes, bread, etc., in which b.u.t.ter or other fats are used, and in custards, puddings, ices, and numerous other desserts.
16. b.u.t.tERMILK.--The milk that remains in b.u.t.ter making after the b.u.t.ter fat has been removed from cream by churning is known by the name b.u.t.termilk. Such milk is similar to skim milk in composition, and unless b.u.t.ter is made of sweet cream, b.u.t.termilk is sour. b.u.t.termilk is used considerably as a beverage, but besides this use there are numerous ways in which it may be employed in the preparation of foods, as is pointed out in various recipes. An advantage of b.u.t.termilk is that its cost is less than that of whole milk, so that the housewife will do well to make use of it in the preparation of those foods in which it produces satisfactory results.
17. ARTIFICIAL b.u.t.tERMILK.--Several kinds of sour milk that are called b.u.t.termilk are to be had, particularly at soda fountains and restaurants. While they are similar to b.u.t.termilk they are not the same, because they are produced artificially from whole or skimmed sweet milk.
The usual method employed in the making of these artificial b.u.t.termilks, as they may well be called, consists in adding to sweet milk tablets containing lactic acid or a certain culture of bacteria that induce fermentation, very much as yeast does, and then keeping it at about body temperature for a number of hours in order to allow the milk to thicken and sour. Such milks exert a beneficial action in the digestive tract, and their food value, provided they are made from whole milk, is just as high as that of the original sweet milk. Artificial b.u.t.termilks therefore prove a valuable source of food supply for persons who find them palatable and who do not care for sweet milk. Their food value may be increased by adding cream to them.
18. SOUR MILK.--Ordinary milk contains large numbers of bacteria that produce fermentation. When it is allowed to stand for some time, these bacteria act upon the sugar, or lactose, contained in the milk and change it into lactic acid. This acid gives to the milk a sour taste and at the same time causes the casein of the milk to become a ma.s.s known as _curd_, or _clabber_. This ma.s.s continues to grow sour and tough until all the milk sugar is converted into lactic acid, so that the longer the milk stands, the more acid it becomes. Sour milk, however, is useful in the preparation of various dishes, such as hot breads and griddle cakes.
[Ill.u.s.tration: FIG. 1]
19. WHEY.--When the curd is completely removed from milk, as in making cheese, a clear, light, yellowish liquid known as whey remains. Whey is composed of water, minerals, and milk sugar or lactic acid, and is the least valuable part of the milk. The ingenious housewife will never be at a loss to make use of this product, for, while its food value is slight, the minerals it contains are important ones. Whey is sometimes used to furnish the liquid for bread making and, in addition, it may be used as a beverage for persons who cannot digest food as heavy as milk itself.
20. COMPARISON OF FOOD VALUES OF MILK PRODUCTS.--So that the housewife may become familiar with the food values of milk products, there is here given, in Fig. 1, a graphic table for the comparison of such products.
Each gla.s.s is represented as containing approximately 1 pint or 1 pound of the milk product, and the figures underneath each indicate the number of calories found in the quant.i.ty represented. The triangle at the side of each indicates the proportion of ash, protein, fat, carbohydrate, and water, the percentage composition being given at the side. Housewives as a rule fully appreciate the food value that is to be found in whole milk and cream, but such products as skim milk, b.u.t.termilk, and whey are likely to be ignored.
CHARACTERISTICS OF WHOLESOME MILK
21. So far as the housewife is concerned, the qualities that characterize wholesome milk are without doubt of great interest. She may know of what use milk is in the diet and the food substances of which it is composed, but unless she understands just what const.i.tutes milk of good quality, as well as the nature of inferior milk, she cannot very well provide her family with the kind it should have. Therefore, to a.s.sist her in this matter, the characteristics of wholesome milk are here discussed. Such milk, it will be well to note, must be of the right composition, must not be adulterated, must be fresh--that is, not older when delivered than is permitted by law--and must be as clean as possible.
22. STANDARD OF MILK COMPOSITION.--The housewife usually judges the quality of milk by the amount of cream that rises to the top when milk in a bottle is allowed to remain undisturbed for some time. This is really an excellent test, because milk that contains only a small amount of cream is of poorer quality than that which contains a larger amount; in other words, the more cream milk contains, the higher will be its food value and the greater its energy-producing ability. Then, too, milk that is rich in cream usually contains proportionately large amounts of protein and sugar.