抄録
In order to clarify the substances responsible for the offensive odor in fish, aromatic hydrocarbons, which play an important role as a hexane extract, were examined by gas chromatography using symmesitylene as a standard. It was proved that the concentration of aromatic hydrocarbons was high in the river water and in the bottom mud where the fish with offensive odor lived. Such hydrocardons were also found in a high concentration in the muscles and digestive organs of the fish with offensive odor, but was not detected in their liver, or in the fish in breeding ponds and in Ayu living in Nagara Bridge basin. Therefore, fish were kept in a tank with constant concentration of aromatic hydrocarbons and the taste of fish was examined at regular intervals. At the same time, concentration of aromatic hydrocarbons in the internal organs of the fish was analyzed. Accumulation of aromatic hydrocarbons was recognized in internal organs except in the liver, and the offensive odor appeared on the 40th day. At the time, 0.25 ppm of toluene, 0.23 ppm of benzene, 0.02 ppm of m-, p- and o-xylene were detected in the muscles. This value agreed with the concentration of aromatic hydrocarbons in the fish with offensive odor. These results suggested that aromatic hydrocarbons were responsible as substances giving the offensive odor to fishes.
