Chemical Studies on the substance of Fish Smell II. Pyridine Group compounds as the Substances concerned with Fishy Smell

Abstract

At present trimethylamine is a single substance that is assured to be the one which causes fishy smell and at the same time causes the smell of freshless marine fish. Smell of freshwater fish and fresh fish is not same one caused by trimethylamin, but presumably those smell which is given off from mucilaginous substance produced from fish skin. If we wipe the skin of fresh and odourless herrings with a gauze and dried it rapidly, the gauze does not give off fishy smell. But when the gauze is wet, we find the development of just same smell given off from freshwater fish after a few houres. If the water of carp culture pond is concentrated, fishy smell of the water resembles to pyridin's. With p-quinon reaction of pyridin we have found that it was apparently positive reaction. In fact 1/10⁴ solution of pyridine has the fresh water fish-like smell. We have found moreover that δ-aminovaleraldehyde and δ-aminovaleric acid which are produced by oxidation of pyridine have also fishy smell. The mechanisms of these components which causes fishy smell are as follows. ??