壳聚糖对火龙果汁澄清效果的影响

Effects of Chitosan on Clarification of Pitaya Juice

用壳聚糖为澄清剂对火龙果汁进行澄清试验,研究壳聚糖添加量、澄清时间、澄清温度、p H值等工艺条件与火龙果汁透光率的关系。在单因素试验的基础上,通过正交试验确定壳聚糖澄清火龙果汁的最佳工艺条件为壳聚糖添加量1.6 g/L,澄清时间60 min,澄清温度20℃,p H值5.0。澄清后,火龙果汁透光率达95%以上,火龙果汁中的可溶性固形物、蛋白质和总糖的含量基本保持不变,果胶和可溶性蛋白质大量清除,提高了火龙果汁的贮藏稳定性。

The experiments on the clarification of the pitaya juice is carried out by the use of the chitosan as a clarifier. The relationships among the technical conditions, such as chitosan usage, clarifying time, temperature, and p H, the transmittance of the pitaya juice are investigated. On the base of the single factor analysis,the optimum technical conditions of the clarification by the chitosan are obtained by orthogonal analysis. The results show that the optimum conditions are chitosan usage 1.6 g/L,temperature 20 ℃,p H 5.0 and clarified for 60 minutes. The transparency is over 95% after clarification. The contents of soluble solids,protein and reducing sugar are almost the same after clarification. Removing both the pectin and some proteins improved the stability of pitaya juice for storage.