库尔勒香梨汁无硫护色剂的优化

库尔勒香梨果汁容易在加工过程中产生褐变现象,传统工艺采用亚硫酸钠进行护色,但是使用不当会损害人体健康。本研究筛选库尔勒香梨汁的无硫护色剂,首先选取柠檬酸、氯化钠和L-半胱氨酸进行单因素试验,然后以库尔勒香梨汁的亮度L值作为响应值,进行响应面分析。结果表明,柠檬酸对库尔勒香梨汁褐变的抑制作用最大,氯化钠次之,L-半胱氨酸最弱;最优复合护色剂为0.36%柠檬酸、1.22%氯化钠和0.03%L-半胱氨酸的复合溶液,此时果汁的L值为83.85±2.81,与预测值相近。

Optimization of Sulfur Free Color Protection Agents for Korla Pear Juice

Korla pear juice is prone to browning during processing. Sodium sulfite is used as color protection agent in traditional process, however it could damage humans health with improper using. In order to screen the optimum sulphur-free color preservation for korla pear juice, citric acid, sodium chloride and L-cysteine were selected for single factor experiment and response surface analysis was conducted with the L value of Korla pear juice as response value. Results showed that browning was most inhibited by citric acid and least affected by L-cysteine. The optimal composite color preservation formula was citric acid 0.36%, sodium chloride 1.22% and L-cysteine 0.03%. The L value of Korla pear juice treated with this color protection agent was 83.85±2.81, which was consistent with the predicted value.