Anatomy of an Egg

ShellBumpy and grainy in texture.An eggshell is covered with as

many as 17,000 tiny pores. It is a semi-permeable

membrane, which means that air, odors, and moisture can pass through its pores.

Inner and Outer Membranes

Lying between the eggshell and the egg white, these two transparent protein membranes provide efficient defense against bacterial invasion.

They’re partly made of keratin, a protein that’s also in human hair.

Air CellAir space forms when the contents of

the egg cool and contract after the egg is laid.

The air cell usually rests between the inner and outer membranes and at the egg’s larger end. The air cell grows larger as an egg ages.

AlbumenThe egg white is known as the

albumen.

Alternating layers of the albumen contain approximately 40 different proteins and water.

ChalazaeThick ropes of egg white, the

chalazae hold the yolk in the center of the egg.

Like anchors, they attach to the yolk’s membrane and to the lining in the eggshell.

Vitelline Membrane

A clear membrane that encloses the yolk.

Yolk

The yolk contains protein, water, some fat, and most of the vitamins and minerals of the egg.

These include iron, Vitamin A, Vitamin D, phosphorus, calcium, and B Vitamins.

YolkYolk color ranges from a hint of

yellow to a deep orange, according to the feed and breed of the hen.

More Egg Notes…One egg = 1 ounce of lean

cooked meat

=

Eggs are the best source of complete proteins with lots of vitamins and minerals.

More Egg Notes…Many experts recommend

limiting the use of egg yolks and whole eggs because they are high in cholesterol.

Egg whites are cholesterol free. ◦For this reason, many people use

egg substitutes.

More Egg Notes…Cracked eggs can contain

harmful bacteria which can cause foodborne illnesses.

Discard any eggs that become cracked or broken during transportation or storage.

More Egg Notes…

Store eggs in your refrigerator. Fresh eggs can be stored for 4 to

5 weeks in the frig.