Abstract:The effects of several factors on the alcalase-catalyzed hydrolysis of soybean protein, such as the enzyme dosage, temperature, pH value and reaction time, were studied. The orthogonal test showed that the optimized hydrolysis conditions were as follow: pH value of 7.5, reaction temperature of 70 ℃, alcalase dosage of 20 μL/g protein, substrate concentration of 60 g/L, and total reaction time of 4 h. Under these conditions the hydrolysis degree of soybean protein reached 24.1%.