壳聚糖固定化果胶酶在枇杷果汁澄清中的应用

以戊二醛为交联剂,壳聚糖为载体固定化果胶酶,对其在枇杷果汁澄清中的应用进行研究。结果表明:固定化果胶酶澄清枇杷果汁的工艺条件为:固定化酶浓度为50 g/L(果汁),果汁pH值为3.8,果汁体积分数为60%,酶解温度和时问分别是50℃和2 h。固定化果胶酶比游离酶处理枇杷果汁的澄清效果好,固定化酶酶解后果汁的糖度没有变化,酸度略有下降,渣汁分层速度加快,果汁色泽由褐色转变为黄色,冷热稳定性也提高了。

The Application of Pectinase from Aspergillus niger Immobilized to Chitosan in Clarification of Loquat Juice

Pectinase from Aspergillus niger was immobilized with chitosan and crosslinked with glutaral- dehyde.The process conditions of loquat juice clarification treated with the immobilized pectinase were inves- tigated.The results showed the process conditions:amount of immobilized enzyme given for 50 g/L juice, pH value for 3.8,concentration of loquat juice for 60%,and 50℃for 2 hour.The clarification effects of im- mobilized enzyme were better than free enzyme.Using immobilized enzyme to hydrolyze the pectin in juice, the sugar content had no change,when the titratable acidity had a slight decrease.The separation between sediment and juice became easier.Meanwhile,the color of loquat juice turned into yellow,and showed higher stability to cold and heat.