Tarako, which is mainly prepared from the Walleye Pollock ovary, is a popular seafood product in Japan. However strange taste of the product has been reported, which is thought to be related to ovarian maturity. However, this remains to be confirmed. In this research, sensory assessment, electric taste sensor analysis and chemical analysis were carried out. Results confirmed that there is the difference in taste depending on ovarian maturity. However the amount of hydroperoxide, i.e., TMA/TMAO, showed no marked difference. However, the amount of the amino acids conferring the bitterness was higher in immature ovaries than in sufficiently mature ones.
