With today being World Chocolate Day, it is important to remember the role that chocolate and Hershey Chocolate Corporation played in keeping US troops fighting in WWII. Not only did it boost morale but it also provided much-needed calories. The Hershey chocolate ration bars were the precursor to the candy and desserts found in the modern-day MRE (Meals Ready to Eat).

In 1937, the concept of the Hershey chocolate bar emergency rations was created when Captain Paul Logan (from the office of U.S. Army Quartermaster General), William Murrie (President of the Hershey Chocolate Corporation) and Sam Hinkle (Hershey Chemist) met to discuss a way to meet the needs of the Army overseas. During the meeting Captain Logan provided the chocolate company with very specific requirements: “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.”

Sam Hinkle, the lead chemist, developed the final formula which was approved by Captain Logan for mass production. Many claimed the chocolate bars were very bitter in comparison but they served their purpose.

The final ingredients were: chocolate liquor, sugar, skim milk powder, cocoa butter, oat flour, vanillin. Sugar was decreased and chocolate liquor increased to give the bar a less appealing taste than normal chocolate bars. The formula created a heavy paste that had to be pressed rather than poured into moulds. A four ounce bar contained 600 calories. After three days of experiments with blending and processing, Captain Logan gave his approval and a small quantity of four ounce bars was produced. Captain Logan was well pleased with the samples.

The original formula and shape of the ration bar were altered slightly when thiamine hydrochloride was added as a source of Vitamin B1 to prevent beriberi, a disease likely to be encountered in the tropics. These bars were originally called “Logan bars” and later were referred to as Field Ration D.

According to Hinkle, even in the experimental stage it was obvious to the chocolate technologists that sweat and toil, if not blood and tears, lay ahead when the time for quantity production of Field Ration D arrived. Normal chocolate is produced at a flowing consistency when warm and all chocolate machinery is constructed based upon this physical property. The Field Ration D could not flow at any temperature and therefore required the development of special processing methods and machinery.” – Hershey Archives

After the formula was approved and the production machinery was created, Hershey field tested 900,000 “Logan bars,” which were later approved for wartime use with the following adaptations:

New specifications called for the placing of each bar in a heavy cellophane bag, closing the bag by means of a heat seal, inserting this into an individual cardboard carton, securely gluing the carton ends, dipping the cartons in a wax mixture, packing twelve waxed cartons in a master carton, gluing the master cartons top and bottom, packing twelve master cartons in a wooden case, and nailing and steel stripping the case.” – Hershey Archives