不同水解工艺对鱼溶浆蛋白水解效果的影响

Comparative study on the effect of different hydrolysis processes on the hydrolysis of condensed fish soluble protein

本研究采用单酶水解、复合酶水解、酸水解及酶酸耦合水解4种水解工艺对鱼溶浆进行水解,以水解度为标准确定最佳水解工艺。结果表明:单酶水解工艺中,在最优条件下(酶解温度50℃,初始pH 5,加酶量2000 U/g,固液比1∶15)以中性蛋白酶酶解鱼溶浆,其水解度最高值为40.37%;复合酶水解工艺中,中性蛋白酶和碱性蛋白酶复合酶两步水解鱼溶浆水解度最高值为43.38%;酸水解工艺中,盐酸在121℃条件下水解20 min,鱼溶浆水解度最高值为61.63%;酶酸两步工艺中,先用中性蛋白酶酶解1 h,再分别使用20%盐酸和20%柠檬酸在100℃下常压水解60 min,鱼溶浆水解度分别可达72.67%与64.67%。酸水解工艺和酶酸耦合水解工艺具有较高水解度,但因酸水解所得氨基酸液颜色较深且具有较强刺激性气味,不利于后续的加工利用,所以选择酶酸耦合水解工艺。酶酸耦合水解工艺较传统酸解工艺具有对设备和生产条件要求低、产品颜色浅、无刺激性气味的优点,更具有作为生产含高游离氨基酸产品原料的推广应用潜力。

In this study,four hydrolysis processes(single enzyme hydrolysis,compound enzyme hydrolysis,acid hydrolysis,and enzymatic acid coupling hydrolysis)are used to hydrolyze condensed fish soluble.Optimal hydrolysis process is based on the degree of hydrolysis.The results showed that,in the single-enzyme hydrolysis process with the optimal conditions(enzymatic hydrolysis temperature 50℃,initial pH 5,added enzyme amount 2000 U/g,solid-liquid ratio 1∶15),the highest hydrolysis degree of neutral protease hydrolyzed condensed fish soluble is 40.37%.In the compound enzymatic hydrolysis process,the two-step hydrolysis for fish dissolved pulp by the neutral protease and the alkaline protease hydrolyzes is with the highest hydrolysis degree of 43.38%.In the acid hydrolysis process,the hydrochloric acid is reacting at 121℃for 20 min,the maximum hydrolysis degree of the solution is 61.63%.In the enzymatic acid coupling process,after the hydrolysis with neutral protease acting for 1 h,hydrochloric acid and citric acid are respectively used to hydrolyze at 100℃for 60 min.The highest hydrolysis degree of condensed fish solution is up to 72.67%and 67.60%respectively.The acid hydrolysis process and the enzymatic acid coupling process have a higher degree of hydrolysis,but the amino acid solution obtained from acid hydrolysis is darker and has strong pungent odor,which is not conducive to subsequent processing and utilization.So the enzymatic acid coupling process is selected.Compared with the hydrochloric acid hydrolyzate,the citric acid hydrolysis product in the enzymatic acid coupling process has normal color,no pungent odor,which is more potential application to be a raw material for products containing high free amino acids.