Effect of Two Proteases on Enzymatic Character for Hydrolysis of Silver Carp Protein

Conditions of enzymolysis(such as pre-treatment,temperature,substrate concentrations,hydrolysis time and product concentration) of silver carp protein by alcalase and multi-protease were studied.The results showed that the optimum hydrolysis condition of alcalase for silver carp protein was pH 8.0,45 ℃,20 min,protein concentration below 6 %,product amino nitrogen concentration below 2.55 g/L;the optimum hydrolysis condition of multi-protease was pH 6.5,50 ℃,20 min,protein concentration less than 6 %,product amino nitrogen concentration less than 2.25 g/L;hydrolysis with two proteases in two steps could greatly enhance the content of the amino nitrogen and increase the recovery of ammoniacal nitrogen.These results were important for the further utilization of low value fish protein with enzymatic methods.