Is It Blood That Comes Out of Steak? The Truth About Myoglobin

If you have cut into a steak and seen a pool of red liquid on your plate, you have probably wondered: is it blood? The direct answer is no. That red liquid is a mixture of water and a protein called myoglobin. The confusion is understandable, because myoglobin looks similar to hemoglobin, the protein that carries oxygen in blood. But the liquid you see is a natural part of the meat and has nothing to do with the blood that once circulated through the animal.

What Myoglobin Is

Myoglobin is a protein found in muscle tissue. Its job is to store oxygen so muscles have a ready supply during activity. When an animal is slaughtered, most blood is drained from the carcass. What remains in the muscle is myoglobin, which gives raw meat its red color.

The amount of myoglobin varies by species, age of the animal, and which muscle the cut comes from. Beef has more myoglobin than pork or chicken, which is why beef is darker red. An older animal has more myoglobin than a younger one. A cut from a heavily exercised muscle, like the leg, also has more myoglobin than a cut from a less active muscle, like the loin.

When you cook meat, myoglobin changes color. At around 140°F (60°C), it begins to denature and turn from red to pink. At higher temperatures, it turns brown. That is why a rare steak is red inside, a medium steak is pink, and a well-done steak is brown or gray.

Why the Liquid Is Red

Meat is about 75 percent water. When you cook a steak, heat causes muscle fibers to contract, squeezing out water and dissolved proteins. That liquid is mostly water, with some myoglobin and other small proteins mixed in. The myoglobin gives it the red or pink color.

If you let a raw steak sit in a package for a few days, you will see red liquid at the bottom. That is not blood either. It is water released from muscle cells over time, along with myoglobin. The USDA Food Safety and Inspection Service explains that this liquid is “purge” or “weep,” a normal result of moisture loss during storage USDA Food Safety and Inspection Service.

During slaughter, the animal is bled out through the jugular vein. The remaining blood in the capillaries is minimal and cannot account for the amount of liquid on a plate. The red liquid is almost entirely myoglobin and water.

Is It Safe to Eat the Red Liquid?

Yes, the red liquid from a steak is safe to eat. It is just water and myoglobin. There is no health risk from consuming it, as long as the meat has been handled and cooked properly.

The safety of meat depends on its internal temperature, not on the color of the liquid. A rare steak can still have red liquid but can be safe if it has reached the recommended minimum internal temperature of 145°F (63°C) for whole cuts of beef, followed by a three-minute rest, according to the USDA USDA Food Safety and Inspection Service. Ground beef should be cooked to 160°F (71°C) because bacteria can be mixed throughout the meat.

Some people think the red liquid is blood because it looks like it, and because meat is sometimes described as “bloody” when it is rare. But that is a misnomer. The meat industry and food scientists have known for decades that the liquid is myoglobin, not blood.

A Practical Example: Steak Doneness

If you cook a 1-inch thick ribeye steak to 125°F (52°C) and let it rest, the center will be bright red, and the liquid released will be red. At 135°F (57°C), the center will be pink, and the liquid will be lighter pink. At 150°F (66°C), the center will be light brown, and the liquid will be clear or slightly tan. In each case, the liquid is still water and myoglobin, just in different stages of denaturation.

Key Takeaways

• The red liquid from a steak is not blood. It is water and myoglobin, a protein that stores oxygen in muscle tissue.
• Myoglobin gives raw meat its red color and changes to pink or brown when cooked.
• The liquid is safe to eat, provided the meat has been cooked to the proper internal temperature.
• The USDA recommends cooking whole cuts of beef to 145°F (63°C) and ground beef to 160°F (71°C).
• If you have specific health concerns about meat consumption, consult a healthcare professional or a registered dietitian for personalized advice.