What kind of egg is AA egg?

AA-grade eggs refer to eggs whose freshness is above 72 (Huff value) within 48 hours produced in certified breeding bases. Egg quality indicators mainly include the following three aspects: general quality indicators are egg shape index, egg weight and egg proportion; Eggshell quality indexes include eggshell condition, eggshell relative weight, eggshell color and thickness, eggshell strength; Internal quality indicators, namely air chamber height, yolk index and Huffman table. ...