Well beaten... Use a mixer, blender, beater or whisk to beat eggs until they are light, frothy and evenly colored.
Thick and lemon-colored... Beat yolks at high speed with an electric mixer until they become a pastel yellow and form ribbons when the beater is lifted or they are dropped from a spoon, about 3 to 5 minutes. Although yolks can't incorporate as much air as whites, this beating does create a foam and is important to airy concoctions such as sponge cakes.
Add a small amount of hot mixture to eggs/egg yolks... When eggs or egg yolks are added to a hot mixture all at once, they may begin to coagulate too rapidly and form lumps. So, stir a small amount of the hot mixture into the yolks to warm them and then stir the warmed egg yolk mixture into the remaining hot Mixture. This is called tempering.
Room temperature... Some recipes call for eggs to be at room temperature before eggs are to be combined with a fat and sugar. Cold eggs could harden the fat in such a recipe and the batter might become curdled. This could affect the texture of the finished product. Remove eggs from the refrigerator about 30 minutes before using them or put them in a bowl of warm water while assembling other ingredients. For all other recipes, however, use eggs straight from the refrigerator.
The following cooking terms apply specifically to egg whites.
Separated... Fat inhibits the foaming of egg whites. Since egg yolks contain fat, they are often separated from the whites and the whites beaten separately to allow them to reach their fullest possible volume. Eggs are easiest to separate when cold, but whites reach their fullest volume if allowed to stand at room temperature for about 30 minutes before beating.
Many inexpensive egg separators are available. To separate, tap the midpoint of the egg sharply against a hard surface. Holding the egg over the bowl in which you want the whites, pull the halves apart gently. Let the yolk nestle into the cuplike center of the separator and the white will drop through the slots into the bowl beneath.
Drop 1 egg white at a time into a cup or small bowl and then transfer it to the mixing bowl before separating another egg. This avoids the possibility of yolk from the last egg getting into several whites. Drop the yolk into another mixing bowl if needed in the recipe or into a storage container if not.
Add cream of tartar... Egg whites beat to greater volume than most other foods including whipping cream, but the air beaten into them can be lost quite easily. A stabilizing agent such as cream of tartar is added to the whites to make the foam more stable. Lemon juice works much the same way.
Add sugar, 1 to 2 tablespoons at a time... When making meringues and some cakes, sugar is slowly added to beaten egg whites. This serves to increase the stability of the foam. Sugar, however, can retard the foaming of the whites and must be added slowly so as not to decrease the volume. Beat the whites until foamy, then slowly beat in the sugar.
Stiff but not dry... Beat whites with a mixer, beater or whisk just until they no longer slip when the bowl is tilted. (A blender or food processor will not aerate them properly.) If egg whites are underbeaten, the finished product may be heavier and less puffy than desired. If egg whites are overbeaten. they may form clumps which are difficult to blend into other foods in the mixture and the finished product may lack volume.