真空冷冻干燥紫甘薯叶的工艺研究

为了对采后紫甘薯叶进行充分的开发利用,提高农副产品的附加值及利用率,研究了紫甘薯叶真空冷冻干燥的最佳工艺参数。以冻干后紫甘薯叶的含水量为指标,利用正交试验对冻干过程的3个阶段进行了分析。并以色差变化为指标,采用正交试验研究了紫甘薯叶的最佳护色条件。研究表明:紫甘薯叶真空冷冻干燥最佳工艺过程为:预冻3h,升华干燥8h,解析干燥2h;最佳护色条件为:护色剂ZnCl2、质量浓度500mg/L、温度70℃、时间30s。

Vacuum freeze-drying progress of purple sweet potato leaves

The best parameters of purple sweet potato leaves were studied by using vacuum freeze-drying technology in this paper,the water content of the purple sweet potato leaves after the freeze-drying was as an indicator,the three stages of freeze-drying process were analyzed by orthogonal experiment;the color change was as an indicator,the best conditions of color protection was studied through orthogonal experiment.The results showed that:the best vacuum freeze-drying process of purple sweet potato leaves as follow:the pre-freeze time was 3 h,the sublimation drying time was 8 h,the analytical drying time was 2 h;the best conditions of color protection as follow:the color fixative was ZnCl2,the density was 500 mg/L,temperature was 70 ℃,time was 30 s.