Optimization of enzymatic hydrolysis of Paphia undulta muscle protein by response surface methodology

Paphia( Paphia undulta) is widely distributed in the coastal areas of China.It is rich in protein and low fat.Enzymatic preparation conditions of Paphia undulta muscle protein was studied in the paper. According to the degree of hydrolysis,protein recov- ery rate and sensory evaluation as the index,the hydrolyzed animal protease,neutral protease,flavor protease and papain as hydrolyzed protease,and the best enzyme type and the enzymatic hydrolysis method was obtained by comprehensive index. And with the time,liquid ratio,quantity of enzyme as a single factor,the optimum conditions of enzymatic hydrolysis were determined by using response surface optimization.The results showed that after 3 hours of simultaneous addition by the ratio of 1 ∶ 1 of animal protease and flavor protease enzymatic hydrolysis,the degree of hydrolysis and protein recovery rate of enzymatic hydrolysis product were 22.29% ± 1.02% and 79.95% ± 0.51% respectively,the total score of sensory evaluation was 15.6,which was better compared with other enzymatic hydrolysis methods. Through the single factor and response surface optimization experiment,the optimized conditions were the quantity of enzyme of 1700 U / g,enzymolysis time of 3.5 h,liquid- solid ratio of 3.4 ∶ 1. Under this condition,the degree of hydrolysis was 30.04% ±0.64%,protein recovery rate of was 81.46% ± 0.70%,there was no significant difference( p > 0.05) compared with the predicted value of the degree of hydrolysis and protein recovery rate which were 30.54% ± 0.137% and 82.62%± 0.092%,respectively.The comprehensive score of sensory evaluation was 15.8 with a better flavor and the resultsprovided a reference for the deep processing of Paphia undulate muscle protein.