Foods, their selection and preparation

Several factors affect the volume and stability of foams formed from beating egg white, including the condition or age of the egg, the temperature of the egg white, the rate of beating, and the addition of other materials to the egg white. [101] The more viscous the egg white — a fresh egg usually has a viscous white — the longer it takes to form a foam. Also, the volume is not so great with high viscosity, but the stability is greater, which is very important. Egg whites at room temperature foam more rapidly and to a greater volume than those at refrigerator temperature. A flat hand whip gives a coarse-celled foam, while a rotary beater, either hand or mechanical, gives a fine-celled one of greater stability. This type of beater also saves time and energy. Salt and acids, in the form of common salt and cream of tartar or lemon juice, stabilize the foam, since these substances cause the proteins in the foam to coagulate slightly and give strength to the foam. Sugar increases the strength of the foam so that less air is lost in mixing. Egg as Emulsifying Agent. The pro¬ tein in egg is useful in forming permanent emulsions of oil in liquids as in mayonnaise. The yolk is more effective than the white, although whole egg may be used. This emulsifying property of the yolk is thought to be due to the presence of a compound pro¬ tein called "lecithoprotein.” For the mak¬ ing of mayonnaise, see page 165. Methods of Cooking. Eggs may be served in a variety of ways. Eggs as eggs are con¬ sidered a standard item for the typical Ameri¬ can breakfast and may be used in other meals as well. In the cooking of eggs, there is a develop¬ ment of flavor both from the effect of heat on the egg itself and from the addition of seasonings. Eggs may be cooked in the shell, soft or hard, poached, fried, broiled, baked, scram¬ bled, or made into omelets. One impor¬ tant rule applies to all methods of cooking eggs: for best results in appearance, palatability, and digestibility, always cook eggs at low to moderate temperatures. Fast high- temperature cooking of eggs or of egg dishes results in tough, leathery, unevenly cooked products. Eggs in the Shell. Cooking eggs in the shell is the simplest method of preparing them. For this method, the eggs may be started in cold water or in boiling water. For a cold-water start: Place the eggs in a pan and add enough cold water to cover the eggs by one-fourth inch. Set the pan over the heat. Bring the water to the boiling point and turn off the heat. For soft-cooked, let the eggs remain in the hot water from two to four minutes, depend¬ ing upon the size and the softness desired. Set the pan aside at once if necessary to stop the boiling. When done, cool the eggs in running cold water, just enough so that they may be opened at once. For hard-cooked, bring the water to the boiling point, turn off the heat, and cover the pan. Let the eggs remain in the hot water 15 minutes. Cool immediately under running cold water. For a boiling-water start: Place the eggs in a pan and add enough boiling water to cover the eggs by one-fourth inch. For soft-cooked, cover the pan and let the eggs stand in the hot water for six' to eight minutes* Cool slightly and open the eggs at once. Soft-cooked eggs may be served in or out of the shell, but they should be opened immediately to prevent further cooking.