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Food is prepared for consumption by a number of methods and the method by which the food is prepared either increases or decreases its digestibility, palatability, and general usefulness.

Certain foods, as has already been stated, require a high degree of temperature to make them wholesome, but if this temperature is applied by means of heated fat, as in frying, the food is changed from a wholesome to a more or less indigestible article. In health the organs of digestion are capable of overcoming much of the harm wrought by wrong preparation, but even in the healthy, normal individual a steady diet of fried food will eventually undermine what is known as good digestion. In abnormal conditions (illness) frying is a method seldom, if ever, used.

Preparation of Food.—The various methods to which food is subjected in preparation for human consumption may be summed up as follows: boiling, simmering, steaming, baking, roasting, broiling, frying, sautéing.

Boiling is cooking in water raised to the boiling point, 212° F. (sterilizing). This method is commonly used in the cooking of starchy vegetables and cereals, and in the cooking of green vegetables, such as spinach, carrots, beets, corn, asparagus, etc. Stewing is a form of boiling. As a rule water is used, and the vessel is left uncovered, so that as the food is cooked the surplus moisture evaporates, leaving the food tender. Dried fruits, such as prunes and apricots, are prepared by this method.

Simmering is cooking in water, the temperature of which is not raised to the boiling point, but kept between 200° F. and 210° F. This method is used in the preparation of eggs and dishes in which eggs predominate, since proteins are made tough if subjected to a high degree of temperature. Coddled eggs, for example, are prepared by placing the egg in a clean vessel and pouring over it the boiling water, then covering the vessel and allowing it to stand for ten or fifteen minutes. The vessel and the cold egg reduce the temperature of the water to about 185° or 190° F. and in this way prevent a toughening of the albumen of which eggs are chiefly composed. Soups, broths, ragouts, etc., are prepared by this method.

Steaming is cooking over hot water or by steam. This method may be accomplished on the top of the stove in a “double boiler” or in the oven in a deep covered pan fitted with a “rack” to hold the article to be cooked. Either method allows the vessel in which the food is placed to be surrounded by boiling water, but does not insure sufficient heat to raise the food within to the boiling point.

Baking and roasting are both brought about in the oven. Bread, biscuits, pies and other pastry, potatoes, cakes, etc., are baked, while meats, roast of beef, lamb, veal, mutton, as well as chicken, turkey, duck, and large fish are roasted. The heat in the oven may be intense. The outside or cut surface of the meat is seared, the soluble albumens are coagulated, thus sealing the juices within. If the meat is placed in a pan surrounded by cold water and then placed in the oven, the juices are “drawn out” in the water. These juices contain the flavoring matter or extractives. Meat so treated is not so palatable or highly flavored as that which has first been subjected to intense heat, the water for the gravy added later.

Frying and sautéing is cooking in hot fat. Food may be fried in deep fat, as is demonstrated in the cooking of croquettes, doughnuts, etc., or it may be sautéd in butter or oil in a shallow frying pan or griddle. The latter method is used in making hashed brown potatoes, for example; also in the cooking of griddle cakes, etc.

Broiling.—In broiling or grilling the article to be cooked is exposed to direct heat, either to the blaze or to a very hot surface. The result is the same as in roasting. The outer surface is seared, sealing the juices within. Meat to be broiled is generally cut thinner than that to be roasted. The article, whether it is meat (steak), chops, birds, or chicken, is placed about three inches away from the flames and turned frequently until the surfaces are seared, after which the article is placed in a cooler part of the stove to allow the interior to be cooked. Pan broiling is done on top of the stove. The article to be broiled is placed directly upon a very hot surface, there is no grease used and the meat must be turned frequently to prevent burning.

Poaching.—This term is applied chiefly to the cooking of eggs in a shallow pan of water heated just below the boiling point. To be properly poached an egg must be perfectly fresh, or the white and yolks will run together and present an unappetizing, unpalatable appearance.

The following time-table should be used in the preparation of food to insure correct cooking: