Eggs

Egg is the reproductive body laid by the female encased in a round or oval shell.  The egg consists of the thick, clear white (albumen),  approximately 60% of total weight of egg, and a yellow yolk, approximately 30% of total weight of egg.  The white is 87% water and 10% protein.  The protein in egg whites coagulate at 150 degrees F (65 degrees C).  The yolk consists of 50% water, 16% protein and 32% fat.  The protein in the yolk coagulates at 158 degrees F (70 degrees C).

Eggs are inspected and graded according to their freshness and quality. The color of the eggshell (brown or white) is determined by the breed of hens and they have the same nutritional content. The color of the yolk is dependent on the hen's diet.  The grading system established by the USDA is AA, A, and B and refers to the egg's exterior and interior qualities, not the size of the egg.  The egg size ranges from jumbo, extra large, large, medium, and small. Grade AA means the egg has a firm yolk and a thick white, which does not spread. Grade A eggs have round yolks, thick whites, but have more thin whites than Grade AA. If the egg carton is labeled "fancy fresh" this means the eggs are less than 10 days old. Always check the carton of eggs before buying to make sure there are no cracked eggs. Eggs must be refrigerated and usually keep one month refrigerated. Eggs shells are porous and therefore pick up odors easily, so store eggs in their carton away from strong odors (e.g. Onions). Do not store eggs at room temperature, as eggs will deteriorate more in one day at room temperature than one week refrigerated.

Once cracked, eggs will keep in the refrigerator a couple of days if tightly sealed. Leftover egg whites can be stored in a tightly sealed container in the refrigerator for 7-10 days or frozen for a month. A good way to freeze egg whites is to place them in individual plastic ice cube trays. Once frozen, transfer the whites to a plastic freezer bag. To thaw, simply place in refrigerator overnight. After freezing, the whites tend to be watery and are best used in recipes where the whites are not the sole leavening agent.

Eggs contain a yolk and a white (albumen). The egg yolk is rich in fat and a source of vitamins and minerals. A fresh egg yolk will be rich in color and will stand upright with little spread. Blood spots are not harmful and will disappear with age. Egg yolks add tenderness and color to baked goods. Some recipes call for beating egg yolks and sugar until thick, light, and forms a ribbon. This means beating the yolks and sugar together until the batter will drop from the beaters in a slow ribbon-like shape (this takes about five minutes at high speed).

The egg white is mostly protein. To get maximum volume when beating egg whites they should be at room temperature and make sure your bowl and beaters are clean and free of grease. Copper is the best type of bowl to use. If whites are over beaten the protein molecules will lose their elasticity and the whites will become dry and flaky and won't hold as much air. If this happens, add another white and beat again only until the whites are creamy and glossy. When adding beaten egg whites to your batter, always fold the whites into the heavier mixture. Not vice versa. Fold gently and quickly so as not to deflate the mixture. Add the egg whites in three stages using a rubber spatula. Cut down and through the batter making sure not to over mix. A few unmixed parts are fine as the most important thing is not to deflate the egg whites.

Always use the size egg that is called for in the recipe. If the size is not given, assume it is large. Most eggs used in baking are at room temperature. A quick way to warm eggs to room temperature is to place them in warm water for 10 - 15 minutes, or else leave them out for 30-60 minutes..