It is Myogloben it's what gives beef it's flavor. I usually wash it off the surface of the meat, when the meat is vacuum packed  like that.
I learned what Glatt means. 
https://www.thespruceeats.com/what-is-glatt-kosher-2121752#:~:text=The%20technical%20definition%20of%20glatt,as%20the%20Jewish%20dietary%20laws.
That is a very expensive cut of Beef.