Why does meat sometimes discolor in the refrigerator?

Answer by  Nessamelda (87)

Discoloration, the change in appearance from a clear bright red to a dull brown or gray, occurs when the cut surface of the meat oxidizes. It does not necessarily mean that the meat has spoiled. Vac-sealing the meat preserves the color by preventing oxygen from the air reaching it.

Answer by  nettarae11 (17)

The color of meat will darken or turn a greyish color when the cut surface comes into contact with air. This is called oxidization.