The US Army Field Ration D (D ration or "D Bar"), developed by the Quartermaster Corps, was intended exclusively for survival. It contained three 4-ounce bars of thick, high-calorie chocolate.
Col. Paul Logan developed the bar in 1937 with the intent that it not taste too good, for fear the men would consume it rather than carry it until an emergency arose. He gave these requirements to Hershey: "...a bar weighing about four ounces, able to withstand high temperatures, high in food energy value, and tasting just a little better than a boiled potato."
The D-Ration was designed to be highly portable, readily available for the soldier's emergency nutrition. D-Ration bars were wrapped in aluminum foil, then overwrapped and sealed in parchment paper. These were to replace the old World War I "iron rations." The researcher's intent was to get the highest caloric content possible in the smallest package, and yet retain sufficient palatability.
D-Ration packages and bars.
According to Hershey Chocolate Corporation, the manufacturer, in 1939, they produced 100,000 units per day. By the end of 1945, production lines on three floors of the plant were producing a total weekly output of approximately 24 million units. It has been estimated that between 1940 and 1945, in excess of three billion ration units were produced and distributed to soldiers around the world. Also produced was a three pack of the four ounce bars intended to furnish the individual combat soldier with the 1,800 calorie minimum sustenance recommended each day.
Original U.S. Army Field Ration D and packaging, photographed in 2001.
On 27 August 1942 Hershey Chocolate Corporation received the first of five Army-Navy "E" awards for producing the "D" Ration Bar.
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