With U.S. Grade AA Eggs, the shell must be clean, unbroken, and practically normal. The air cell must not
exceed 1/8 inch in depth, may show unlimited movement, and may be free or bubbly. The white
must be clear and firm so that the yolk is only slightly defined when the egg is twirled before the
candling light. The yolk must be practically free from apparent defects.
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