I'd look a little closer for tracks of bear, skunk, badger, raccoon and opossums. What ever it is will probably be back at some point, food has a way of doing that. If nothing else, I'd try a live trap, some thing like a havaheart for skunk, raccoon and opossums.
edit could look for signs such as feces, hair, a path, parts of comb or anything else you can think of.