Ground meat

Why is day old hamburger red on the outside and brown on the inside?

Oxygen

Because the supermarket puts the old meat on the inside and surrounds it with a half-inch wrapper of fresh meat. Our local one was notorious for this.

This meaty discussion is headed for Cafe Society.

They’ve got a mold that does this, or the butcher just has really good hands?
:slight_smile:

Myglobin.

This is what I recall from about a decade ago. I’m pretty sure it’s right.

Myglobin, which gives meat it’s color, is a little dark. Once exposed to Oxygen(the meat on the outside) it changes to oxymyoglobin, a red color. Hence the meat on the inside can be darker. Once exposed long enough the oxymyoglobin will change to metmyoglobin, a dark brown(and icky).

Linky

I always thought it was because the hamburger was ‘dyed’ red to make it more appealing to the consumer and the darker color was the natural color.

I don’t remember where I heard that, google gives a bunch of hits but none that are particularly reputable. I_Know_Nothing’s answer seems to be the correct one.

Nope. I’ve ground my own burger, and it’s the exact same color as the stuff in the store. And the burger I buy locally from mom-and-pop natural organic blah blah blah farms is also the same color. No dye involved; beef is naturally an appealing red color.

MyOglobin.

I believe Myglobin was a one-man play by William Harvey. :wink:

Maybe you’re thinking of carbon monoxide, which is sometimes used in meat packaging to keep the outside of the meat looking red for longer.

I have heard that plastic wrap used by butchers to wrap meats is oxygen permeable which allows the outside of the ground beef to have constant oxygen contact, keeping the meat red longer. IANAButcher, so I can’t say for sure.

ETA: I just noticed this is confirmed by I_Know_Nothing’s link.

Oxygen: is there anything it can’t do?