Demma was an Orion food. It was the subject of rumor, innuendo, and folklore about its source and its effect on those who eat it. It seemed to be an aphrodisiac or fertility enhancer.
When Kirk was a Lieutenant about the USS Farragut, the galley's refrigeration units had malfunctioned and they were forced to trade for food. However, they could only get several tons of Orion demma. By the time they arrived at Starbase 7, the sick bay had run out fertility control ampules. (TOS novel: Dreams of the Raven)