Your Steak Isn't Bleeding, Here's What That Liquid Is (Video)
Ever cut into a steak to be simultaneously enthralled by and scared of the red liquid leaking from its sides? Well, consider your fears calmed, because that stuff isn't actually blood, science confirms.
The red juice -- charmingly called "weep" or "purge" -- around steaks and other red meat is a result of their freezing and packaging, according to a video by Tech Insider (below). The liquid is simply a mix of water and myoglobin, a protein found in muscle.
Most meat contains about 75 percent water, which freezes and forms sharp crystals when the meat is packaged for transport. The crystals' sharp edges rupture the muscle cells in the meat and cause them to release myoglobin when the meat thaws. The myoglobin combines with water to form that eerie juice.
That's all fine and good, but it begs one question: Why is the liquid red? That, ladies and gentlemen, is because myoglobin contains iron, which gives red meat its signature hue and turns the liquid a blood-like red.
If you're still not convinced, think about it this way. First of all, nearly all blood is removed from meat during slaughter, which is why steak doesn't taste like blood.
Secondly, if red meat actually "bled," white meat would, too. The reason we don't see the same red liquid on cuts of chicken or turkey is because those animals have much lower levels of myoglobin in their muscles -- hence, the basis of the distinction between red meat and white meat, Today I Found Out explains.
If myoglobin gives raw red meat its color, it is also responsible for the darkening of the meat as it cooks. The longer a steak spends on the grill, the darker the myoglobin becomes, and the more well done the steak will be.
So whether you formerly avoided your steak's red juice (or enjoyed it more?) because you thought it was blood, you can now find comfort in the knowledge that it is a far less dramatic substance: red protein water. Have fun impressing your friends with your newfound scientific knowledge of steak.