1. The Structure of Eggs
The hard shell is porous and lined with membranes.
A pocket of air, known as the air cell, lies between these membranes at the wide, round end.
As an egg ages, the air cell gets larger.

2. The Structure of Eggs
Also known as the egg white, the albumen is the thick fluid surrounding the egg yolk.
The albumen gets thinner as an egg ages.
Very fresh eggs have a cloudy-white albumen.

3. The Structure of Eggs The round yellow portion of an egg is the yolk.
It is encased in a thin membrane and floats within the albumen.
The yolk flattens as an egg ages.
Color depends on the hen’s diet.
The two, thick, twisted strands of albumen that anchor the yolk in the center of an egg are called the chalazae.
The thicker and more prominent the chalazae, the fresher the egg.

4. Nutrients in Eggs Excellent source of protein and vitamin B12.
Both the white and the yolk contain protein.
The yolk of the egg contains more vitamins and minerals than the white.
Yolks also contain fats and cholesterol.
The color of the egg shell is not related to its nutrients, flavor, or cooking qualities.
The color of the shell is determined by the breed of the hen.

5. Egg Grade
A USDA grade shield on a package means that the eggs have been federally inspected for wholesomeness.
Determined by the inner and outer quality of the egg.
Inspect using bright lights.
The three egg grades are AA, A, and B.
Supermarkets typically carry AA & A.
Appearances differ when cooked.
AA & A have a thicker white.
Use Grade B for Baking

6. Egg Size
The egg sizes most commonly sold are medium, large, extra large, and jumbo.
Most recipes assume that large eggs will be used.
The price of eggs depends on the size as well as the supply of various sizes.
Size can vary slightly in the same carton.

7. Egg Storage Eggs are highly perishable.
Take eggs home and refrigerate them in their original carton.
Exposed to warm air in the door.
Eggs are porous and may lose quality and pick up aromas and flavors from other foods.
Do not wash eggs.
This could remove the protective coating that prevents bacteria from getting inside the shell.
Raw eggs stay fresh for up to 4 weeks.

8. Egg Substitutes Egg substitutes are an alternative to whole eggs.
They are made by combining egg whites with oils.
You can use substitutes the same as whole eggs.
Because they contain no egg yolks, egg substitutes have no cholesterol or fat and are lower in calories.
They lack some B vitamins.
More expensive.

9. Egg Science
Eggs have special properties that result from their high protein content.
They can act as:
A Binder
A Thickener
A Leavening Agent
An Emulsifier
Because of their many uses, they are found in a wide variety of recipes.

10. Eggs as a Binder How an egg acts as a binder:
The proteins in eggs are shaped like coils.
When the proteins are heated, the coils unwind and join loosely with other proteins.
The new structures form pockets that hold water.
The pockets absorb moisture, and the egg changes from a liquid to a solid state.
This transformation is called coagulation.
Coagulation is what helps eggs act as a binder in foods like meatloaf, and thickens custards such as pumpkin pie.

11. Eggs as an Emulsifier
An emulsifier is a substance that holds together two liquids that normally do not stay mixed, such as water and oil.
How does this work?
In yolk protein, one end of the amino acid bonds with water, but the other end bonds with oil.
This gives egg yolks the power to hold 2 ingredients together.
Examples:
Vinegar and oil in a salad dressing.
Lemon juice and oil in mayonnaise.

12. Eggs as a Leavening Agent
Egg whites act as leavening agents.
When you beat egg whites, air enters the mixture and a foam forms.
An egg white foam adds volume and lightness to baked products such as angel food cake and soufflés.

13. Separating Eggs Different parts have different uses.
Yolks are used in custards, sauces, mayonnaise, and pastry.
Whites are used in meringues and baked items.
To separate an egg:
Use an egg separator.
Helps keep the yolk from bursting and running into the white.
Eggs separate more easily when cold.

14. Cooking Eggs in the Shell
Place a single layer of eggs in a saucepan.
Add water to at least 1 inch above the eggs.
Cover the pan and bring the water to a boil.
Cooking time:
12 minutes for medium-size eggs
15 minutes for large eggs
18 minutes for extra large eggs
Do NOT cook less than 12 minutes!
Pour off hot water and run cold water over the eggs.
Refrigerate them in their shells until ready to use.

15. Poaching Eggs Poached eggs are cooked in simmering water.
Crack the egg right into the simmering water.
Cook about 3-5 minutes.
Use a slotted spoon to remove.
Little to no fat is used.
Usually served with Hollandaise sauce.
Eggs Benedict

16. Scrambling Eggs Scrambled eggs are beaten, then fried.
To make fluffy scrambled eggs, beat the eggs with water.
How to prepare:
Pour the beaten egg mixture into a heated skillet.
As the mixture starts to thicken, lightly stir the eggs with a spatula.
Continue until the eggs are thickened and there is no liquid.
Do not stir the eggs constantly.
This beats out the air and creates small, tough pieces.

17. Baking Eggs
Baked eggs, also known as shirred eggs, are eggs baked in a greased, shallow dish and are often topped with a small amount of milk.
Eggs can also be baked into a quiche.
A quiche is a pie with custard filling, containing such foods as chopped vegetables, cheese, and chopped, cooked meat.

18. Omelets
An omelet is an egg mixture formed into a large, thick pancake, usually filled with ingredients and folded.
Unlike scrambled eggs, the eggs in an omelet are not stirred.
A frittata is an unfolded omelet with fillings stirred into the egg mixture.