Why is my venison browning?

First year butchering/processing a deer ourselves. We just finished grinding and sealing everything earlier today and popped it all in the freezer. I was just looking and noticed everything is turning brown? Is that okay or is the meat spoiled?

First year butchering/processing a deer ourselves. We just finished grinding and sealing everything earlier today and popped it all in the freezer. I was just looking and noticed everything is turning brown? Is that okay or is the meat spoiled?