Science
Myoglobin
The protein in muscle that holds oxygen and gives meat its red color — not blood, despite popular belief.
When you see 'red juice' running off a steak, that's not blood — blood is drained at slaughter. It's water mixed with myoglobin, the same protein that creates the smoke ring. The amount of myoglobin determines whether meat is 'red' (beef, lamb), 'pink' (pork), or 'white' (chicken breast).