Egg Facts

FAT

A concentrated source of food energy containing 9 calories per gram. In addition to supplying energy, fat aids in the absorption of certain vitamins, enhances flavor, aroma and mouthfeel of food, and adds satiety to the diet.

Fatty acids, the basic chemical units of fat, are either saturated, monounsaturated or polyunsaturated.

Saturated fatty acids are found primarily in fats of animal origin (meat and dairy products) and are usually solids at room temperature. Exceptions are some vegetable oils (palm, palm kernel and coconut) which contain large amounts of saturated fatty acids. Saturated fat increases blood cholesterol.

Monounsaturated fatty acids are found in fats of both plant and animal origin. They tend to decrease blood cholesterol levels. Polyunsaturated fatty acids are found primarily in fats of plant origin and in fats of fatty fish. They also tend to decrease blood cholesterol levels.

A Large egg contains only about 5 grams of fat—about 1.5 grams saturated and 2.5 grams unsaturated. Egg recipes which are high in fat and/or saturated fat can often be significantly lowed in fat content by making changes in "traditional" recipe ingredients and cooking methods. ~see Cholesterol

FERTILE EGGS

Eggs which can be incubated and developed into chicks. Fertile eggs are not more nutritious than nonfertile eggs, do not keep as well as nonfertile eggs and are more expensive to produce. Fertile eggs may contain a small amount of male hormone, but there are no known advantages.

FOAM

Air bubbles trapped in liquid albumen when egg white is beaten. When egg white is beaten, it becomes foamy, increases 6 to 8 times in volume and stands in peaks. When the foam is heated, the tiny air cells expand and the egg protein coagulates around them, giving permanence to the foam. Egg white foam is responsible for the structure of soufflés, angel food cake, puffy omelets and meringue.

Egg whites reach their greatest volume if allowed to stand at room temperature for about 30 minutes before beating.

Fat inhibits the foaming of egg whites, so be sure beaters and bowls are clean and that there is no trace of yolk in the whites. Use only metal or glass bowls because plastic bowls tend to absorb fat.

If egg whites are underbeaten, the volume of the finished product will be less than desired. Overbeaten whites form clumps which are difficult to blend with other ingredients. And, because overbeaten egg whites lack elasticity, they cannot expand properly when heated. The finished product may be dry, of poor volume or may even collapse.

The addition of an acid ingredient helps to stabilize the foam. The most commonly used acid ingredient is cream of tartar (1/8 teaspoon for each 1 to 2 whites) although some recipes call for lemon juice or vinegar.

Since salt decreases foam stability, it is best to add it to other recipe ingredients.

Egg white foams should be combined with other ingredients immediately, before they have time to drain or shrink.

Egg yolk and whole egg will also form foams, but the volume is much less than the foam of beaten white. ~see Angel Food Cake, Cooking Terms, Meringue

FOOD GUIDE PYRAMID

Based on nutrition research, the U.S. Department of Agriculture has grouped all of the foods we eat according to the nutritional contributions they make. For a balanced diet that includes all the food groups in good proportions, follow these daily recommendations:

Breads, grains and cereals—6 to 11 servings

Vegetables—3 to 5 servings

Fruits—2 to 4 servings

Meat and meat alternates—5 to 7 ounces

Milk and milk products—2 to 3 servings

Fats, oils and sweets—53 to 93 grams (4½ to 7½ tablespoons) fat at most; 2 to 6 tablespoons added sugar at most

Eggs are included in the meat and meat alternates group because, after mother's milk, they provide the highest quality protein available. One egg = 1 ounce of lean meat, fish or poultry. ~see Biological Value, Nutrient, Protein, Daily Reference Values (DRVs)

FORMATION

A hen requires about 24 to 26 hours to produce and egg. Thirty minutes later, she starts all over again.

The reproductive system of the hen consists of the ovary, the organ where the yolk develops, and the oviduct where the egg is completed. The ovary is attached to the back about halfway between the neck and the tail. The oviduct, a tubelike organ approximately 26 inches long, is loosely attached to the backbone between the ovary and the tail. Most female animals have two functioning ovaries, but the hen uses only one, the left. The right ovary and oviduct remain dormant.

Ovary A female chick is born with a fully formed ovary containing several thousand tiny ova, or future yolks. these begin to develop, one at a time, when the pullet reaches sexual maturity. Each yolk is enclosed in its own sac or follicle.

The follicle contains a highly developed system of blood vessels which carry nourishment to the developing yolk. At ovulation, the follicle ruptures to release the yolk into the oviduct. A double-yolked egg is the result of two yolks being released at the same time. Rupture occurs at the stigma line, an area of the follicle which has no blood vessels. ~see Blood Spots

Oviduct The infundibulum, also know as the funnel, captures the ovulated yolk. This is where fertilization, if it occurred, would take place. After about 15 minutes, the yolk passes along to the magnum. Here, in approximately 3 hours, the albumen is deposited around the yolk. As the albumen is formed, the yolk rotates, twisting the albumenous fibers to form the chalazae.

The next site of activity is the isthmus where the two shell membranes are formed in about 1¼ hours.

The egg has now reached it full size and shape. It passes along to the uterus to acquire, after 19 hours, it shell, shell color and bloom. After a few minutes' pause in the vagina, the uterus inverts through the vagina, the cloaca (the junction of the digestive, urinary and reproductive systems) and the vent to release the egg outside the hen's body. Laying of the egg is known as oviposition.

During formation, the egg moves through the oviduct small end first. Just before laying, it is rotated and laid large end first. A young hen lays small eggs. The size increases as she gets older. ~see Composition

FREE-RANGE EGGS

True free-range eggs are those produced by hens raised outdoors or that have daily access to the outdoors. Due to seasonal conditions, however, few hens are actually raised outdoors. Some egg farms are indoor floor operations and these are sometimes erroneously referred to as free-range operations. Due to higher production costs and lower volume per farm, free-range eggs are generally more expensive. The nutrient content of eggs is not affected by whether hens are raised free-range or in floor or cage operations.

FREEZING EGGS

If you receive a windfall of eggs far beyond your capacity to use within a few weeks, they can be frozen—not in the shell, of course. Freeze only clean, fresh eggs.

Whites Break and separate the eggs, one at a time, making sure that no yolk gets in the whites. Pour them into freezer containers, seal tightly, label with the number of egg whites and the date, and freeze. For faster thawing and easier measuring, first freeze each white in an ice cube tray and then transfer to a freezer container.

Yolks Egg yolks require special treatment. The gelation property of yolk causes it to thicken or gel when frozen. If frozen as is, egg yolk will eventually become so gelatinous it will be almost impossible to use in a recipe. To help retard this gelation, beat in either 1/8 teaspoon salt or 1½ teaspoons sugar or corn syrup per ¼ cup egg yolks (4 yolks). Label the container with the number or yolks, the date, and whether you've added salt (for main dishes) or sweetener (for baking or desserts).

Whole eggs Beat just until blended, pour into freezer containers, seal tightly, label with the number of eggs and the date, and freeze.

Hard-cooked Hard-cooked yolks can be frozen to use later for toppings or garnishes. Carefully place the yolks in a single layer in a saucepan and add enough water to come at least 1 inch above the yolks. Cover and quickly bring just to boiling. Remove from the heat and let stand, covered, in the hot water about 15 minutes. Remove with a slotted spoon, drain well and package for freezing.

Hard-cooked whole eggs and whites become tough and watery when frozen, so don't freeze them.

To use frozen eggs Thaw frozen eggs overnight in the refrigerator or under running cold water. Use yolks or whole eggs as soon as they're thawed. Once thawed, whites will beat to better volume if allowed to sit at room temperature for about 30 minutes.

Substitute 2 tablespoons thawed egg white for 1 Large fresh white.

Substitute 1 tablespoon thawed egg yolk for 1 Large fresh egg yolk.

Substitute 3 tablespoons thawed whole egg for 1 Large fresh egg.

Use thawed frozen eggs only in dishes that are thoroughly cooked.

FRENCH TOAST

Egg-soaked bread, sautéed in butter. Another name for this breakfast specialty is Pain Perdu, French for lost bread. Thrifty cooks of the 15th century developed this trick for using nearly stale bread which would otherwise be lost.

FRESHNESS

How recently an egg was laid has a bearing on its freshness but is only one of many factors. The temperature at which it is held, the humidity and the handling all play their part. These variables are so important that an egg one week old, held under ideal conditions, can be fresher than an egg left at room temperature for one day. The ideal conditions are temperatures that don't go above 40°F. (4°C.) and a relative humidity of 70 to 80%.

Proper handling means prompt gathering, washing and oiling of the eggs within a few hours after laying. Most commercially produced eggs reach supermarkets within a few days of leaving the laying house. If the market and the buyer handle them properly, they will still be fresh when they reach the table.

It is not true that freshness can be judged by placing an egg in salt water. A carefully controlled brine test is sometimes used to judge shell thickness of eggs for hatching purposes but has no application to freshness of table eggs.

How important is "freshness"? As an egg ages, the white becomes thinner and the yolk becomes flatter. These changes do not have any great effect on the nutritional quality of the egg or its functional cooking properties in recipes. Appearance may be affected, though. When poached or fried, the fresher the egg, the more it will hold its shape rather than spread out in the pan. On the other hand, if you hard cook eggs that are at least a week old, you'll find them easier to peel after cooking and cooling than fresher eggs.

FRIED EGG

~see Cooking Methods, fried

FRITTATA

An unfolded Italian version of the omelet. A frittata cooks on top of the stove until almost set. It is finished off under the broiler or turned over or the pan may be removed from the heat, covered and allowed to stand until the top of the omelet is completely cooked.

A frittata may contain any combination of cooked vegetables, seafood, meat, poultry, grain or cheese you like.

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