Have you ever opened a package of ground beef that looked bright red on the outside, only to find that the meat underneath was gray or brown? It may seem like a sign that the beef is old or spoiled, but this color difference is often completely normal. The appearance is largely related to how the meat reacts to oxygen rather than automatically indicating that something is wrong.

Ground beef gets its color primarily from myoglobin, a protein found in muscle tissue. When myoglobin comes into contact with oxygen, it produces the bright-red color commonly associated with fresh beef. The outer portions of the package receive more oxygen, while the meat in the center has much less exposure, which can make it look gray or brown. Once the interior is exposed to air, its color may change as well.

However, color alone should not be used to determine whether ground beef is safe to eat. Look for other signs of spoilage, such as a strong unpleasant odor, a sticky or slimy texture, damaged packaging, or evidence that the meat has been stored at an unsafe temperature. If the beef has been handled or stored improperly, that is a much more important concern than a gray center by itself.

To keep ground beef safe, refrigerate it promptly after purchasing and avoid leaving it at room temperature for extended periods. If you do not plan to use it soon, freezing it is a practical option. Properly refrigerated ground beef is generally best cooked or frozen within one to two days. So, if you notice a gray or brown center, don’t automatically assume you were sold bad meat—consider the meat’s smell, texture, packaging, and storage conditions as well.