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Uses of Nutrients in the Body
e. g., white (albumen) of eggs, curd (casein) of milk, lean meat, gluten of wheat, etc.
Builds and repairs tissue.
FATS........ Are stored as fat........ e. g., fat of meat, butter, olive oil, oils of corn and wheat, etc.
CARBOHYDRATES Are transformed into fat. e. g., sugar, starch, etc.
Protein.
Fats.
Carbohydrates.
Mineral matters.
All serve as fuel to yield energy in the forms of heat and muscular power.
MINERAL MATTERS (ASH) Share in forming bone, assist in digestion, etc. e. g., phosphates of lime, potash, soda, etc.
The Proteins form tissue and muscle for growth and repair. They are found in lean meat, white of eggs, gluten of wheat, curd of milk, beans, peas, etc.
The Fats are either used as fuel foods or stored as fat. Examples are the fat of meats; the oils of corn, peanut, and olive, etc. The Carbohydrates, such as starch and sugar, are fuel foods. All three of the above, Protein, Fats, and Carbohydrates, serve as fuel to yield energy in the forms of heat and muscular power. The Mineral Matters (ash) share in forming bone and in acting as body regulators. They are found in fruits and in many vegetables. Water enters every tissue, regulates body temperature, and aids in the work accomplished by all other foods.
In planning a day's meals, fuel foods, growth-and-repair foods, and mineral matters should be provided in correct proportion. This subject is further discussed in the chapter on Balanced Rations.
Purpose of Cooking. -The purpose of cooking foods is threefold: to increase their nutritive value and render them more digestible; to develop their flavors; and to safeguard health by destroying germs and parasites.
Many vegetables are indigestible if uncooked; this is not only because their coarse cellular structure must be softened by cooking, but because most vegetables are made up largely of starch; and starch in its raw state cannot be appropriated by the body. Witness the pain caused by eating green apples, due to the presence of uncooked starch. In the case of the ripe fruit, the starch has been partially cooked by the heat of the sun's rays. Exposure to heat, as in boiling, causes the starch grains to swell and burst the hard outer coverings in which they are enclosed. The starches thus softened and released are converted during the digestive process into sugar, which the body so readily appropriates. If the starch grains are subjected to a greater degree of heat, as in baking, a greater-a chemical change-takes place which approaches the changes made during the process of digestion. For this reason, toasted and twice-baked breads are easily assimilated. It follows, therefore, that starchy foods require thorough cooking. This does not mean, however, that all foods should be made very soft, nor that they should be predigested. The digestive system of a healthy person likes to do its own work, and both desires and requires a certain amount of bulk. This much-needed bulk is largely supplied by the cellulose, or fibre-structure of vegetables, which has no nutritive value in itself, but has great mechanical value. In some forms it is not too coarse to be used uncooked, as in lettuce and celery; but as found in potatoes, the cereal grains, and in other combinations with starches, it needs to be softened by the cooking which renders the starch digestible. Cooking develops and intensifies the flavors which render food more appetizing, and therefore more digestible. This is particularly true of meats. Cooking also serves to destroy germs and parasites; and, in the case of meats, to break down their heavy muscular fibres and tough connective tissues.
Albuminous Foods should be cooked at a low temperature. This refers principally to meats and eggs. Meats belong to the protein group of food, and contain much fibrin which closely resembles albumen. The simplest form of albumen is seen in the white of an egg. Heat hardens albumen, long exposure to intense heat rendering it almost insoluble, and therefore indigestible. For this reason eggs should be cooked at a low temperature; soups and broths likewise to extract the full flavor of the juices. Baked and roasted meats should first be exposed to intense heat, to sear the surface and thus prevent the rich juices from escaping. After a coating is formed, the balance of the cooking should be done at a low temperature.
These two principles, thorough cooking for starchy foods, and low temperature for albuminous foods, are a key to the reasons for the various methods given in the chapters that follow. Different Methods of Cooking.-Foods are cooked in their own juices, or by the use of water, or by the use of fats. Roasting, baking, broiling, and pan-broiling are examples of cooking foods in their own juices.
Roasting, which means cooking before a clear open fire with exposure to air, has practically gone out of use with the passing of the open fireplace for cooking, although gauze-door ovens are a substitute. By roasting, the flavor is better developed, and the juices are better retained than by any other method of cooking meats.
Baking, which means cooking in a closed oven, has largely taken the place of roasting.
Broiling, or cooking on a grill over glowing coals, or exposed to gas flames, is the nearest to roasting of the methods of cooking now employed. Pan-broiling is cooking in a sauté pan or spider without the use of either water or fat.
Boiling, stewing, braising, and fricasseeing are various methods of cooking by use of water, and are explained in the chapter on "Meats," page 59.
Frying and sautéing, methods of cooking by the use of fats or oils, are also explained on page 60.
Measurements. On the last page of this book will be found tables of weights and measures. The standard measuring cup holds one-half pint, and all measurements are level. Fill measures more than full, then draw a knife across the top to level. Just as a skilled workman enjoys using good tools, so the good and intelligent cook enjoys having a well-equipped kitchen work-room. There is not only inspiration for the cook in such inexpensive conveniences as the transparent glass measuring cup, the handy nest of measuring spoons, the flexible kitchen spatula, the copper wire dish mop, the revolving egg-beater, and the potato-ricer, 1 2/3. 1 3/4 12 13. 14