Formation of Mutagenic Substances during Smoking-and-Drying (Baikan) of Bonito Meat

Abstract

Smoked, dried bonito (katsuobushi) products, which are a typical class of Japanese food, contain mutagenic heterocyclic amines, 2-amino-3, 8-dimethylimidazo[4, 5-f]quinoxaline (MeIQx) and possibly 2-amino-3, 4, 8-trimethylimidazo[4, 5-f]quinoxaline (4, 8-DiMeIQx). It is now shown that mutagenicity possibly due to these mutagens is generated during the smoking-and-drying (baikan) of fresh bonito meat to prepare the products. Though the benzo[α]pyrene content in the tar portion of the intermediate sample of katsuobushi processing was 20-40 times higher than that in the residual meat portion, the major part of the mutagenic activity still remained in the bonito meat after removal of the peripheral tar.