150 



FOODS 



requirement is seemingly often overlooked, and with dire effect. The 

 importance of the art of cookery, to mankind can scarcely be overesti- 

 mated. To the trained nurse, the nursery-maid, and the physician 

 few things are more important, but at present the last learns scarcely 

 more about it than the second, and not nearly as much as does the first. 

 In many diseases, and for more and more with the increasing number of 

 antitoxins, the proper feeding of the patient is three-quarters of his 

 proper treatment, and to direct this proper feeding intelligently, the 

 physician requires a practical as well as a theoretical knowledge of foods 

 and their ideal preparation. Every medical curriculum might not 

 improperly include a demonstration-course in actual cookery to complete 

 its discussion 'of food and dietetics. 



The preparation of food for man includes the boiling, stewing, roasting, 

 baking, broiling, frying, preserving, freezing, brewing, and arranging 

 of soups, meats, breads, vegetables, salads, pastry, desserts, preserves, 

 ices, fruits, and beverages. We will consider the chief of these culinary 

 processes, and especially their relations to the physiological value of food. 



FIG. 74 



Changes of starch-cells in cooking: a, cells of raw potato with starch-grains in natural con- 

 dition; b, cells of a partially cooked potato; c, cells of a thoroughly boiled potato. (United 

 States Department of Agriculture Year-book, 1900. 



In general, the application of heat to food more or less (1) destroys 

 the cellulose shell about the grains of starch in carbohydrates, coagulates 

 some proteids and dissolves others, and softens the fat; (2) macerates 

 and makes more easily masticable flesh and vegetables; (3) destroys 

 parasites of nearly all sorts; (4) renders the food more grateful both to 

 the taste and to the intestines by its warmth; and (5) develops flavors, 

 especially in meats. 



Of all modes of cooking, boiling is undoubtedly the most common, 

 it being easiest and cheapest. Boiling differs from stewing only in degree, 

 for the latter process is boiling continued until the food falls apart from 

 solution of the connective-tissue of meats or of the rough cellulose frame- 

 work of vegetables. The boiling water penetrates the mass of food and 

 cooks it homogeneously, and so differs much in its effects from roasting 

 or broiling. Boiled meats are less easily digestible than those roasted 

 or broiled, for the soluble proteids are coagulated and rendered hard and 



