Abstract
In order to find out a suitable method for freezing and storage of chub mackerel, a kind of fatty fish, the round fish were frozen experimentally by liquid nitrogen spraying metho d (LN2-freezing) and usual contact freezing as a control experiment, and stored at -10, - 20 and -40°C for 6 months. Quality change of the fish meat during frozen storage was checked using indices such as pH, POV and VBN. The quality was also evaluated by histological observation and sensory score.
Results are as follows :
(l)The present data did not always show the superiority of ultra-rapid freezing with LN2 in quality of frozen-stored chub mackerel as compared with contact freezing, regardless of storage temperature.
(2) It seemd to be necessary to store fatty chub mackerel at a temperature below -20°C, such as -25 - -30°C being advisable.
(3) Quality of chub mackerel was observed to change more markedly than that of sardine tested already during frozen storage.
