Eggs-actly

What may be the most crucial part of your morning eggs? The yolk? The whites? No, the air. All chicken eggs have a little pocket of air between the shell and the goo. This air pocket forms as the contents of the egg cool and contract right after the egg is laid. Eggs are graded based on the amount of air in them. A bright light is shined on one side of the egg, and the size of the air pocket is measured by the shadow on the other side of the egg. The smallest pockets earn the egg a Grade AA.

As an egg ages, the contents contract even more, and air seeps into the pocket through pores in the shell. When the egg goes bad, the pocket is big enough to make the egg float in plain water. Thus if you're worried that you have a spoiled egg, drop it into a glass of water. If the egg sinks, you can eat it.