Lots of things change color once the air hits them. Like guacamole for instance turns brown and yucky when left open. You did not even tell us the brand name you are talking about so people can't even tell you if they have noticed the same thing. Most cat food companies have a website with contact information. If you are concerned about the product's safety for your cats, I would contact them directly and ask if this is normal.

Allie answered on 1/28/12. Helpful? / 0