Originally Posted by kitchenelf
It's not blood suzi - don't think that it is. I think it's a protein (now that makes sense) that when exposed to air turns red.
If not, someone please chime in.
Kitchenelf is correct. It's not blood. The red color in the meat juice comes from myoglobin, which is the main pigment in meat (muscle tissue). It is different from hemoglobin, which is the main pigment in blood. They share some similarities, but they are 2 distinctly different things. I learned this from the book, Kitchen Science, by Howard Hillman.