CHANGES IN SOLUBILITY AND ATPASE ACTIVITY OF CARP MYOFIBRILS DURING FROZEN STORAGE UNDER PHOSPHATE BUFFER CONDITIONS

The solubility and specific ATPase activity of carp myofibrils suspend ed in 5 and 50 mM phosphate buffer (pH 6.8) were compared at three dif ferent storage temperatures, -4, -11, and -26 degrees C, in the absenc e of neutral salts throughout a period of 167 days. Allocated ATPase a ctivities in salt-soluble and salt-insoluble fractions were also calcu lated from solubility and specific ATPase activity. The extent of the decrease in solubility and in the four kinds of allocated ATPase activ ity in the salt-soluble fraction was smaller with a decrease in storag e temperature at both buffer concentrations. It is suggested that myof ibril insolubilization occurred without complete inactivation of ATPas e activity.