On Food and Cooking

Egg grade has nothing to do with either
freshness or size, and is not a guarantee of egg
quality in your kitchen. It’s an approximate
indication of the quality of the egg back at the
ranch, at the time it was collected. Because
candling isn’t foolproof, USDA definitions
allow several eggs per carton to be below
grade at the time of packing. Once the eggs
have arrived in stores, the below-grade
allowance doubles, because egg quality
naturally declines with time, and jostling and
vibration during transport can cause the white
to thin out.
Generally, only the two top grades, AA and
A, are seen in stores. If you’re going to use
eggs fairly soon and will be scrambling them
or making a custard or pancakes, then the
higher grade isn’t worth the higher price. But
if you go through eggs slowly, or like your
hard-boiled yolks well centered and your
poached and fried eggs neat and compact, or
are planning to make a meringue, soufflé, or