魚類筋肉構成たんぱく質に関する研究-X

スケトウタラ冷凍すり身中のアクトミオシン含量について

抄録

Quantitative determinations of actomyosin in various kinds of frozen surimi prepared from Alaska-pollack muscle were made by measuring total Ca²⁺-ATPase activity after exhaustive extraction of the actomyosin.
1. In rozen unsalted surimi, sucrose and sorbitol (added to 5%, respectivity) were found to have remarkable inhibitory effects on the enaturation of actomyosin while Na-polyphosphate (added to 0.2%) had no effect.
2. In frozen salted surimi (NaC1 added to 2.5%), sorbitol had a remarkable in-hibitory effect on the denaturation of actomyosin and sucrose, a lesser one (sugars added to 10%, respectively). Relatively larger amounts of aggregated actomyosin retaining Ca²⁺-ATPase activity were found in frozen salted surimi than in frozen unsalted surimi. Aggregated actomyosin was determined as Ca²⁺-ATPase activity in the ‘precipitated’ fraction, collected by high speed centrifigation (15, 000xg, 60 minutes) and redissolved in 0.6 M KCI, pH 6.8.
3. The amounts of actomyosin in salted and unsalted frozen surimi showed little change during frozen storage for 4 months at -20°C.
4. Quantitative determinations of actomyosin in frozen unsalted surimi of grades A, AB and C gave average values of 173, 154 and 147 μ moles Pi liberated/min/10g frozen surimi, respectively. A definite correlation between the grade of surimi and the amounts of actomyosin in surimi was suggested.
5. The amounts of actomyosin in muscle dewatered by squeezing, in unfrozen surimi, and in frozen surimi were determined to be 224, 178 and 155 μ moles Pi liberated/ min/10g of wet weight, respectively.