The amounts of extractable protein decreased with storage time
and sharply decreased to 10.37% in fillets stored for 12 days
(Table 2). Our results showed that the extractable protein content
was affected by storage time. Fish fillets contained the lowest
amount of Exp on day 12, suggesting that proteolysis of the salmon
fillets continuously occurred at 4 C. Meanwhile, no significant difference
(p > 0.05) was observed between the control and irradiated
groups at the end of storage. The results indicate that irradiation
did not significantly affect the contents of extractable proteins,
and therefore the decrease may be caused by endogenous enzymes
or bacterial spoilage