Technology Study on the Hydrolysis of Tilapia by Papain

[Objective] The research aimed to discuss the preparation method of polypeptide hydrolysate by hydrolyzing tilapia proteins by papain. [Method] In a single factor test, the effects of different factor on the hydrolysis of tilapia proteins by papain were studied. With the hydrolysis degree as index, the optimum hydrolysis technology for hydrolyzing tilapia by papain was confirmed through the orthogonal test. [Result] Single factor test showed that when the hydrolysis time was about 5 h, the substrate concentration was 4%, the enzyme addition was about 5 500 U/g, pH value was 7.0～7.5, the temperature was 50℃, the hydrolysis effect of tilapia by papain was better. The orthogonal test showed the effects of 3 factors in order were the enzyme addition substrate concentrationhydrolysis time. The optimum hydrolysis technologies were as follows: pH value of hydrolysate of 7.5, the enzyme addition of 5 500 U/g, substrate concentration of 4%, hydrolyzing for 6 h at 50 ℃. Under these conditions, the hydrolysis degree could reach 37.89%. [Conclusion] Enzymolysis liquid with higher hydrolysis degree could be obtained from hydrolyzing by papain with strong fish aroma and normal color, which could be used to make condiments and oral liquid etc.