Beef’s color is driven mostly by myoglobin, a muscle protein that changes with oxygen exposure, temperature, time, and packaging. When meat “blooms” into bright cherry red, that’s oxymyoglobin forming on the surface, not proof of superior freshness. Vacuum-packed steaks may look purple or dark, then redden after opening. Ground beef can be red outside and brown or gray inside simply because less oxygen reaches the center. These shifts are normal chemistry, not automatic signs of danger or deceit.

What truly matters is the full story around that package. Check dates, temperature, seal integrity, and leakage. At home, refrigerate promptly, store raw meat where juices can’t drip, and never rely on color to judge doneness—use a thermometer, especially for ground beef. Trust your nose and hands more than your eyes: strong off-odors, sliminess, or tackiness are bigger red flags than browning alone. In the end, marketing sells color; science protects your kitchen.