I don't always have this happen, but if I don't butcher myself, I take the deer to a butcher friend up north and he hangs it in a cooler at 38 degrees for up to 15 days. It creates a black charcoal crust on the deer and then when butchered the crust is removed. Probably an eighth of an inch. You lose some meat but the taste and texture is much, much different then a quickly butchered deer. I brine sometimes but the doc wants me to stay away from the salt so the aging process is my preferred approach.