What Is the Red Stuff in Meat? A Clear Explanation

If you have ever cut into a steak or opened a package of ground beef and noticed a reddish liquid pooling on the plate or in the tray, you have probably wondered what it is. The direct answer is that it is not blood. The red stuff in meat is mostly water mixed with a protein called myoglobin. Myoglobin is the same protein that gives meat its red color, and the liquid you see is simply that protein dissolved in water that has been released from the muscle cells.

What Myoglobin Does in Meat

Myoglobin is a protein found in the muscle tissue of animals. Its job is to store oxygen and deliver it to the working muscles. This is similar to hemoglobin, which carries oxygen in the blood, but myoglobin stays inside the muscle cells. The amount of myoglobin in the meat depends on the animal’s age, species, and how much the muscle was used during the animal’s life.

A young chicken breast, for example, has very little myoglobin, which is why it looks pale. Beef from a mature cow has much more myoglobin, giving it a deep red color. The liquid that pools in a package is mostly water (about 75-80% of meat is water) with a small amount of myoglobin dissolved in it. When you cook the meat, the myoglobin changes color from red to brown as it heats up, which is why well-done meat turns gray-brown. The USDA Food Safety and Inspection Service explains that the color of meat is a good indicator of doneness, but it is not a reliable measure of safety USDA Food Safety and Inspection Service.

Why the Liquid Is Not Blood

A common misconception is that the red liquid is blood. In a properly slaughtered animal, the blood is drained during the slaughter process. The USDA requires that livestock be bled out, so very little blood remains in the muscle tissue. What you see in the package is not blood; it is myoglobin-rich water. If you have ever seen a bright red pool in a plastic-wrapped steak tray, that is myoglobin and water that has been released as the meat ages and the cell walls break down.

How Myoglobin Changes Color

The color of meat changes depending on how much oxygen the myoglobin is exposed to. This is why the inside of a fresh cut of beef looks darker purple-red than the outside. The surface turns bright cherry-red when it is exposed to oxygen in a process called oxygenation. The American Meat Science Association notes that this bright red color is what consumers often associate with freshness American Meat Science Association.

The Three States of Myoglobin

Myoglobin can exist in three main forms that affect the color of meat:

• Deoxymyoglobin: This is the form when no oxygen is present. It gives meat a purplish-red color. This is the color you see on the inside of a freshly cut steak.
• Oxymyoglobin: When the meat surface is exposed to oxygen, myoglobin binds with it and turns bright red. This is the color you see on the surface of a steak in the store.
• Metmyoglobin: Over time, the myoglobin can oxidize further and turn brown. This is the same color change that happens when you cook the meat. It is a sign of aging or that the meat has been exposed to air for a long time.

The liquid that leaks out is mostly oxymyoglobin or deoxymyoglobin, depending on how much oxygen it has been exposed to. That is why the liquid can look bright red or slightly darker.

Does the Red Liquid Affect Safety or Quality?

The presence of red liquid in a meat package does not mean the meat is unsafe or of lower quality. It is simply a natural result of moisture loss. The amount of liquid can vary depending on how the meat was processed, how long it was stored, and how it was handled. Some producers use absorbent pads in the tray to soak up this liquid, but the liquid itself is harmless.

What You Can Do With the Liquid

You can cook the meat with the liquid still in the pan, or you can pat the meat dry with a paper towel before cooking. Patting it dry helps the surface brown better when searing. The liquid is mostly water, so it will evaporate during cooking. If you are making a stew or braise, the liquid adds some flavor and color to the cooking liquid. There is no need to rinse the meat, as the USDA advises against washing raw meat because it can spread bacteria around your kitchen USDA Food Safety and Inspection Service.

Key Takeaways

• The red liquid in meat is not blood. It is mostly water mixed with the protein myoglobin.
• Myoglobin stores oxygen in muscle cells and gives meat its red color.
• The color of the liquid and the meat changes based on oxygen exposure and cooking temperature.
• The liquid is safe and does not indicate spoilage or poor quality.
• Patting meat dry before cooking helps with browning, but rinsing is not recommended for food safety reasons.