莴苣组合干燥工艺参数的响应面法优化

Optimization of combined drying technology for lettuce based on response surface methodology

以莴苣为原料,通过试验探讨了在热风真空组合干燥条件下,热风温度、中间转换点含水率、切片厚度和真空度等因素对莴苣组合干燥过程的影响;通过响应面法分析了热风温度、中间转换点含水率、切片厚度及真空度与莴苣复水比、干燥时间之间的关系,建立了其回归数学模型;并利用多目标非线性优化分析法对干燥工艺进行了综合优化,获得了莴苣组合干燥的最佳工艺参数:热风温度50℃,中间转换点含水率(w.b.)40%,切片厚度5mm,真空度20kPa.

Using lettuce as a raw material, the effects of hot-air temperature, intermediate conversion moisture content, slice thickness and vacuum degree on the drying of lettuce by combination of hot-air and vacuum were explored. The hot-air temperature, intermediate conversion moisture content, slice thickness and vacuum degree were the influence factors, and the drying time and rehydration ratio of lettuce were the experimental indices, and the relationships between the experimental indices and the influence factors were analyzed through the response surface methodology. The regression mathematical models were estab- lished. The optimized technological parameters of hot-air and vacuum combined drying are the 50 ℃ hot-air temperature, 40% intermediate conversion moisture content （w. b. ）, 20 kPa vacuum degree and 5 mm slice thickness.