Abstract:In order to take full advantage of pseudosciaena polyactis and increase their added value,the hydrolyzing of small yellow croaker fish protein were studied in this manuscript.The enzymatic hydrolysis of protein in small yellow croaker fish by alcalase,flavourzyme,papain and protemex were firstly studied and papain was selected for further study with the degree of hydrolysis(DH) as index.Then the effect of papain on the the degree of hydrolysis(DH) was investigated by single factor test and orthogonal experiment.The results of the single factor test showed that DH increases with the amount of enzyme,hydrolysis time,the ratio of small yellow croaker fish to water and the temperature and the optimum conditions listed as follows: 0.2 mg/dL enzyme,reaction time 4 h,the ratio of small yellow croaker fish to water 1∶3.Furthermore,the optimum conditions was determined by the orthogonal experiment,and listed as follows: the amount 0.4 mg/dL,hydrolyzed for 4h at 60 ℃ and the ratio of mall yellow croaker fish to water at the ratio of 1∶5.The effect those factors on DH was the ratio of small yellow croaker fish to water>temperature> amount of enzyme>time.
