Anatomy of an Egg Shell Bumpy and grainy
Anatomy of an Egg
Shell �Bumpy 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 Cell �Air 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.
Albumen �The egg white is known as the albumen. Alternating layers of the albumen contain approximately 40 different proteins and water. �
Chalazae �Thick 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.
Yolk �Yolk 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.
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