And as for a can of beans that was 13 years old?

I am not shocked that it was edible. But there was a definite risk involved. Canning food has been done for more than 200 years. In 1820, William Perry led an expedition to the North Pole. On the ship was canned meat. At least one can was not used and later wound up in the basement of a British museum. In 1938, the can was opened and the contents were chemically analyzed before being fed to a cat, who ate the meat with no ill effects. The meat had been in the can 118 years. But most experts believe the reason it survived was that the can had been stored at very cool temperatures for its entire life. Had the can been lost in the desert, it probably would have been inedible within 10 years.

All storage limits and expiration dates are guidelines, and many of them are very conservative. The Internet Grocer claims you could easily get a 15 to 20 year life from most of their canned foods even though they are only guaranteed for 3 years.