Preliminary Preparation
The successful preparation of eggs for their use as a food demands that certain points must be observed by the housewife. For instance, she must see that the eggs she uses are in the right condition; that the shells are properly broken for the most convenient removal of the egg; that the parts of the egg are separated in the right way in case the whites and the yolks are to be used separately; and that the eggs receive the right treatment for the purpose for which they are to be used. Attention to all these points not only will insure the most satisfactory results, but will enable the housewife to supply her family with food that is extremely wholesome and nutritious.Exterior Condition of Eggs.--As has been explained, clean eggs are the most desirable, but it is not advisable to wash eggs that are to be kept for even a short time, as washing them removes the natural coating that helps to prevent the entrance of bacteria. However, as it is necessary that the shells be perfectly clean before they are broken or before the eggs are cooked, the eggs may be washed or wiped with a damp cloth immediately before such processes.
BREAKING OF EGGS.--In cookery, it is usually desirable to break an egg shell so that the yolk will not run into the white; that is, so that these can be kept separate. While there are several methods of doing this, the housewife should adopt the one that is most convenient for her. A quick method that is often employed consists in striking the shell on the edge of the pan or the bowl into which the contents are to be put. A preferable method, however, is illustrated in Fig. 7. It consists in striking one side of the shell, midway between the ends, a sharp blow with the edge of a knife. The advantage of this method will be evident after a trial or two, for it will be found that the depth of the cut made by the knife can be so gauged that there will be little danger of breaking the yolk. Besides, fragments of the shell are not likely to fall into the bowl or the pan with the contents of the egg.
SEPARATING OF EGGS.--Frequently recipes require that the yolks and whites of eggs be beaten separately before being added to the other ingredients. When this is the case, care must be exercised in taking the egg from the shell. The method by which this is most easily accomplished is illustrated in Fig. 8. As will be observed, the shell is first broken as nearly as possible into halves and then, while the egg is poured from 1/2 of the shell into the other, the white is dropped into a dish and the yolk is retained in the shell. During this process, the yolk should remain intact in its delicate membrane, for if it becomes mixed with the white the lightness of the white will be injured. To separate the yolk from the white is not difficult when eggs are fresh, but as they become stale the membrane surrounding the yolk grows weak and breaks easily. If the yolk breaks and any of it falls into the white, it must be completely removed before the white is beaten.
BEATING OF EGGS.--Sometimes eggs are cooked in the shell and other times they are used alone just as they are removed from the shell, as in the frying and poaching processes; however, when they are to be combined with other ingredients, they are usually beaten. Eggs are beaten for the purpose of mixing the yolk and the white or of incorporating air to act as a leavening agent when the eggs are heated in the cooking process. Various utensils, such as a fork, an egg whip, or an egg beater, may be employed for beating eggs, the one to select depending on the use to which the eggs are to be put. The rotary, or Dover, egg beater, previously described as a labor-saving device and illustrated in Fig. 9 (a), should be used to beat either whole eggs or the yolks of eggs when they are to be used in custards, mayonnaise, cakes, puddings, etc., as it will beat them sufficiently light for such purposes. However, for the beating of egg whites, use should be made of a fork or of an egg whip similar to that shown in (b), because the whites must be lifted instead of stirred for the incorporation of air, and it is only with a utensil of this kind that this can be accomplished. Then, too, more air can be incorporated into the whites and the volume of the egg thereby increased by means of a fork or an egg whip than by an egg beater. An important point to remember in this connection is that eggs can be beaten more successfully when they are cold and have had a pinch of salt added to them.
In the beating of eggs, it should be remembered that for some purposes, as in making some kinds of sponge cake, they are beaten until nearly frothy, as shown in Fig. 10, when they do not stand up nor cling to the whip; whereas, for other purposes, as in making meringue, they are beaten until they are stiff enough to stand up well and to adhere to the whip, as Fig. 11 shows. When egg whites are to be beaten stiff, care should be taken not to continue the beating too long. If this is done, they will become dry and will break up into small pieces, a condition that will mean a loss of some of the air that has been incorporated. It is well also to observe that egg whites should always be beaten in the same direction and that the same motion should be continued throughout the beating, for a change of direction or motion always causes a loss of air. A final precaution to take is never to allow egg whites to stand after they are beaten. If this is done, the leavening power of the eggs is reduced, because the air soon escapes from beaten eggs and leaves underneath them a clear liquid that can never be beaten up. For instance, eggs that are to be used for boiled icing should not be beaten until the sirup has finished boiling. However, eggs that have been separated but not beaten may stand for a couple of hours, provided they are covered and kept in a cool place.