Abstract
The effect of preparatory treatments for the cooking of fish, such as pickling, soaking in soybean paste (Miso-zuke), salting and drying, to the change of inosinic acid in fish flesh was studied.
(1) During the pickling, the enzymatic degradation of inosinic acid in common mackerel flesh was partially suppressed following the decrease of pH of the flesh.
(2) During the Miso-zuke, the degradation of inosinic acid in common mackerel flesh was promoted, by the phosphatase originated from soybean paste, and by the addition of Mirin (a sort of cooking wine) or Sake (rice wine) to soybean paste, to make so as to ethanol concentration in the paste to about 6%, the degradation due to soybean phosphatase was suppressed effectively, but the phosphatase activity originated from common mackerel flesh was not affected by this treatment.
(3) During th salting and the drying, the enzymatic degradation of inosinic acid in horse mackerel flesh was suppressed according to the decrease of the water activity of the flesh.
