Perhaps the best place to begin a discussion about the egg business would be with the egg itself. There is just a nine-ounce difference between a dozen medium and a dozen jumbo eggs. A dozen large eggs, the standard in the retail marketplace, weighs twenty-four ounces. A dozen medium eggs, commonly used in the food service sector, weighs twenty-one ounces—just three ounces less. These slight differences can become big factors when calculating what it costs to produce a dozen eggs.
Egg grades—AA, A, and B—have nothing to do with egg size or shell color. Rather they are used to rate shell cleanliness and uniformity and the condition of the egg’s interior. Under examination and candling, an AA egg will have a clean, unbroken shell with even shape and shell surface. The air cell will be 1/18th-inch or less in depth, and regular in shape. The white will appear clean and firm, and the yolk will be centered and free of defects.
An A-quality egg will also have a clean and unbroken shell. The air cell will be 1/4-inch or less in depth and fairly uniform. The white should be clear, although not quite as firm as that of the AA egg. The yolk should be fairly centered, have a more defined outline, and should also be free of defects such as meat or blood spots.