Astronaut food evolved through the years from flavorless food consumed by straw to dehydrated and freeze-dried food coated with gelatin or oil, eventually leading to scoopable pouches of cold meals. Back in 1937, Hershey had invented a hard-to-melt chocolate bar as a wartime ration — which came to be known as the Tropical Chocolate Bar —and by the time of Apollo 15, NASA wanted to send it to space.