[quote=Susan
There is no water in MREs, so I am assuming a separate source of water for cooking, where you wouldn't have to depend on the moisture in cans, for instance. Let's not muddy the question with multiple uses.
[/quote]

There is plenty of water in MREs; that is the reason they are relatively heavy and ready to eat, hot or cold, with zilch prep time. I would say that they are essentially canned chow in expensive packaging. For what they are, they are actually pretty good. I have been fortunate to have eaten mine on firelines rather than foxholes.

I am not sure about their packaging - it is not straight foil but is some kind of mylar/foil blend - seems to work.

Freeze dried/dehydrated is another matter. You definitely need water to make those edible.
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