Abstract:Myofibrillar proteins were prepared and stored at 25℃ and 4℃. The effects of alkaline protease on the degradation and gel properties of myofibrillar protein were studied using the degradation rate,sulfhydryl content,surface hydrophobicity,Ca2+ATPase activity and gel properties as indexes. For the myofibrillar proteins with alkaline protease,the degradation rate increased with prolonging storage time at different temperatures. The surface hydrophobicity,Ca2+ATPase activity,contents of total and active sulfhydryl groups increased followed by a decrease,and reached the maximum under the conditions of 25℃ and 2.0 h,or 4℃ and 2.5 h. In addition,the Ca2+ATPase activity reached the maximum at 0.5 h. As the storage time prolonged,the waterholding capacity and gel strength decreased,and the whiteness decreased followed by an increase. The SEM showed that the protease destroyed the threedimensional network structure of the gel to an extent.