storage The Mf Ca-ATPase activity in the control group decreased sharply to approximately 14% of the initial value after 45 daysof frozen storage, and further decreased gradually until 90 days,showing a biphasic denaturation pattern (Fig. 1). In contrast, the Mf Ca-ATPase inactivation with PPS was significantly higher than that of the control group (p < 0.05), though gradually decreased up to the 90 days. The Mf Ca-ATPase in the weever Mf increasedwith increasing PPs addition