Flavor improvement of boiled fish by addition of fermented rice bran “Nuka”

Flavor improvement of boiled fish by addition of fermented rice bran, “Nukamiso”, and raw rice bran was investigated. Jack mackerel fillet was boiled with lactic acid fermented rice bran or raw bran. Change of flavor during storage at 4℃ was monitored using a gas chromatography-mass spectrometer, an electronic nose and a sensory test. Addition of fermented or raw rice bran prevented the generation of trimethylamine during boiling and the increase of aldehydes such as pentanal, octanal and nonanal during storage. The result of the electronic nose corresponded to the increase of aldehydes during storage. A significant decrease of fishy odor in the raw rice bran sample was confirmed by the sensory test. The fermented rice bran sample was not popular with the panel of young tasters who had never eaten “Nukazuke”, a type of Japanese traditional pickle made with fermented rice bran.