[manaboutown]

I have experienced both canned and frozen food go bad. A can that bulges contains food gone bad.

About once a year I go through my canned, boxed and frozen food. If it is over a year out of date I toss it. I have found cans that bulged and I could not get rid of them fast enough.

Canned food undergoes chemical changes over time, just like the oil in your crankcase or the gasoline in your gas tank. They are all organic material. Food out of a ten year old can will not be as nutritious or taste as good as food out of a year old can. MREs, K-rations, C-rations and the like are designed to last a long time and they do, as do Spam and Velveeta. These are food products I would only consume in or during an emergency when I could not obtain fresh food.