K rations

The K-ration was an individual daily combat food ration which was introduced by the United States Army during World War II. It was originally intended as an individually packaged daily ration for issue to airborne troops, tank corps, motorcycle couriers, and other mobile forces for short durations. The K-ration provided three separately boxed meal units: breakfast, dinner (lunch) and supper (dinner).

In 1941, Dr. Ancel Keys (a University of Minnesota physiologist) was assigned by the U.S. War Department to design a non-perishable, ready-to-eat meal that could fit in a soldier's pocket as a short-duration, individual ration. Keys went to a local supermarket to choose foods that would be inexpensive, but still be enough to provide energy. He purchased hard biscuits, dry sausages, hard candy, and chocolate bars. He then tested his 28-ounce, 3,200 calorie (871 gram, 13,400 kJ) meals on six soldiers in a nearby army base. The meals only gained "palatable" and "better than nothing" ratings from the soldiers, but were successful in relieving hunger and providing sufficient energy. The new rations were initially intended as individual rations suitable for short durations only, to be used for a maximum of fifteen meals before supplementation or replacement with 'A-ration' or 'B-ration' field rations. They were soon called the "paratrooper ration", since paratroopers were the first to be issued the ration on an experimental basis.

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