In terms of inactivation rate constant of myofibrilla Ca-ATPase, the thermal stability of Pacific myofibrillar protein was found to be comparable to those of Pacific mackerel and sardine but it became unstable at higher temperature and in an acjdic condition. Addition of sucrose or sorbitol increased effectively the stability of this myofibrillar protein.
On the basis of the above findings, the frozen surimi of Pacific pomfret was prepared. During frozen storage, the quality of the frozen surimi was evaluated by measuring the amount of soluble protein and Ca-ATPase total activity. The Kamaboko forming ability of the same material was assessed by jelly strength and the folding test. The frozen surimi from the alkali (0.25-0.50% NaHCO3)-washed umscle showed the highest quality, which was slightly inferior to that of SA grade frozen surimi of Alaska pollack.
The frozen surimi prepared from the minced muscle without washing was first washed with water after thawing and subjected to suimi preparation. The quality of this surimi and its Kamaboko forming ability were remarkably improved, being comparable to that of the alkaliwashed muscle frozen surimi. On the other hand, the quality of the frozen surimi using frozen muscle of the Pacific pomfret was considerably inferior.
