Adipic acid

Acid, flavoring agent, antioxidant: soft drinks, fruit-flavored drinks, edible oils, gelatin desserts.
Adipic acid is sometimes used as the acid in bottled drinks and throat lozenges. Because it has little tendency to pick up moisture, adipic acid may be used to supply tartness, and it may account for the je ne sais quoi taste of highly manufactured powdered products, such as gelatin desserts and fruit flavored drinks. It is occasionally added to edible oils to prevent them from going rancid. Rats, and presumably humans, metabolize adipic acid without any difficulty.