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Most of us won't touch leftovers in the fridge after more than a couple of days, but U.S. soldiers often feast on barbecue sandwiches will into their two year shelf life.

By lowering the pH and controlling the water and oxygen levels inside each package, government food technologists created an environment inhospitable to mold and bacteria.

Available in chicken or beef, the pocket-size MRE's (meals ready to eat) require no water, refrigeration, or heating.   This makes them ideal for servicemen and women when they are in the field.

With 300 calories, 11 grams of protein, and 35 grams of carbs, they pack a nutritional punch in a small package.    But I'm not sure how many of us would be comfortable eating food that should be well beyond petrified.