http://consumerist.com/2010/03/this-1-y ... -well.html
I've seen even older McDonalds food that hadn't been intentionally kept. I can vouch that the hamburgers, fries, and McNuggets all retain their original appearence even at age four and having been stored in non-climate controlled conditions where ants were confirmably present. Left outside in the open and having observed this "food" for two weeks I can testify that ants, flys, and dogs wouldn't touch the stuff. In fact, my friend's dog actually took one sniff and growled at the stuff. The specimens are now comfortably residing in a landfill where they will no doubt be discovered by archeologists in the future. It was that fated encounter almost ten years ago that lead me to conclude that McDonalds "food" is remanufactured industrial waste by products.
And a local nitrition shop has a McDonald's "beef patty" on a glass covered dish which they say the've had on display now for eighteen years. It still looks fresh too. Well, that is if anyone can truly call a flat, grey, round, slab of "meat" fresh looking.