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BBC - Future - How army rations helped change food

When soldiers go into the field, they carry with them tiny miracles of engineering. And we're not just talking about weaponry: some very technical and forward-thinking research has gone into military meals. They must be light and easy to carry, capable of staying edible even after weeks in the hot sun, supply the surprisingly high number of calories that soldiers in the field need (more than 4,000 a day), and, of course, not cost the taxpayer an inordinate amount. That has led to some clever tricks of science that have even made their way into the goods you may find on your shopping list.