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What would make a meatloaf that had been fully cooked at 300 degrees for 1 hour and 50 minutes and has reached a temperature of 180 degrees turn pink or red inside? Could it be that a dye has been added to the hamburger? Actually I use ground chuck...Any ideas?
No, not dye. Usually these are made with part ground pork or sausage and you will see that some turns red/pink while other stays brown, even in the same loaf. The meat loaf cooked this way is safe to eat.