Why Ground Beef Can Be Red Outside and Gray Inside

Why Ground Beef Can Be Red Outside and Gray Inside
Ground beef often looks bright red on the surface because oxygen reacts with myoglobin, a natural meat pigment. The interior receives less oxygen and may appear grayish-brown instead.

A darker center alone does not mean the beef has spoiled. However, color cannot confirm safety, and harmful bacteria may be present without changing its appearance or smell.

Discard meat that has an unpleasant odor or a sticky, tacky, or slimy texture. The absence of these warning signs does not replace proper refrigeration and attention to storage time.