I also have a box containing "Food and Water for One Person for 14 Days." It's completely intact, and dated 1961. In the box are a few cans of water, some vitamin-C tablets, and a can of "MPF." MPF? That's Multi-Purpose-Food. Shaking the can reveals that it is some sort of powdered substance.
I'd have to have to use it - its a valuable antique.
Very important ya know! ; )