"The Red Juice in Raw Red Meat Isn't Blood"

"The level of myoglobin in meat is what ultimately dictates whether it will be "red," "dark," or "white." The muscles in red meat are used for standing, walking, and other frequent activity, and they're made up of slow-twitch muscle fibers. Red meats' high levels of myoglobin make it red or dark in color.

White meat, on the other hand, is made up of fast-twitch muscle fibers and is comprised of muscles used for quick bursts of activity only. They get energy from glycogen and contain little myoglobin."
http://articles.mercola.com/sites/articles/archive/2014/10/25/myoglobin-red-meat.aspx

Huh. Things I never knew.