When the concentration of chitosan solution was 2.0 % , the composition of coagulation liquid was 15% NaOH: 75% ethanol = 4:1 (in Volume) , and it was treated with 5.0% glutaraldehyde for 6 hours, globular cross-linked chitosan carrier was made. The application of pectinase immobilized on globular cross-linked chitosan in clarification of loquat juice was studied. The results showed that the process conditions were as follows : amount of im- mobilized enzyme given for 50 g/L juice, pH value for 3.0, concentration of loquat juice for 40% , and 50 ~C for 1.5 hour. The transmittancy of loquat juice was 75.8% after immobilized enzyme was repeatedly used seven times. The clarification effects of immobilized enzyme were better than that of free enzyme. Using immobilized enzyme to hy- drolyze the pectin of juice, the sugar content and titratable acidity had no change. The separation between juice and sediment became easier. The color of loquat juice become thin yellow, and showed higher stability to cold and heat.%以戊二醛为交联剂,NaOH与乙醇为凝结液组成成分,壳聚糖为载体制备了球形交联壳聚糖固定化果胶酶,对其在枇杷果汁澄清中的应用进行了研究。结果表明,固定化果胶酶澄清枇杷果汁的工艺参数为：固定化酶质量浓度为50 g/L（果汁）,果汁pH值为3.0,果汁浓度为40%,酶解温度和时间分别是50℃和1.5 h,在重复使用7次后果汁透光率仍保留有75.8%。固定化果胶酶比溶液酶处理枇杷果汁的澄清效果好,酶解后果汁的糖度与酸度没有变化,汁渣分层速度快,果汁色泽为淡黄色,冷热稳定性也有所提高。
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