不同干燥工艺下脱皮油莎豆干燥特性及品质研究

采用先湿法脱皮再干燥的方式可以简化油莎豆榨油前工序，提高榨油效率。为探究最适合的干燥工艺，本文以湿法脱皮油莎豆为研究对象，探究其薄层热风干燥特性，对比分析不同干燥工艺下脱皮油莎豆品质及所制取油脂的品质变化规律，以期为油莎豆产业化发展提供支持。本实验分别将油莎豆在自然干燥以及热风温度为50℃、60℃、70℃，风速0.8 m/s条件下进行干燥，再测定油莎豆的色泽、硬度、复水性以及脱皮油莎豆所制取油脂的品质。实验结果显示，样品干燥后亮度值、泛红度降低，硬度升高；热风50℃样品复水性最好，自然干燥次之，热风70℃下样品复水性最差；热风干燥条件下，随着风温的升高，所制得的油莎豆油的酸价及过氧化值均呈增加趋势，但是远低于国家标准中对食用植物油的要求。

Drying characteristics and quality of wet peeling Cyperus esculentus under different drying processes

The method of wet peeling followed by drying can simplify the process before oil extraction and improve oil yield and quality of Cyperus esculentus. In order to explore the most suitable drying process for wet peeling C. esculentus, in this paper, thin layer hot-air drying characteristics of wet peeling C. esculentus were studied, and the quality changes of wet peeling C. esculentus and oil were compared under different drying processes. Hot-air temperatures of 50℃, 60℃, 70℃ with wind speed of 0.8 m/s were set and natural drying was set as control. The color, hardness, rehydration of wet peeling C. esculentus, and the quality of C. esculentus oil were determined after different drying processes. The results showed that, the brightness and redness of sample decreased, meanwhile the hardness increased after drying. The rehydration of hot-air samples at 50℃ was the best, followed by natural drying, and the worst at 70℃. Under the condition of hot-air drying, with the increase of air temperature, the acid value and peroxide value of the prepared oil increased, but it was far lower than the national standard for edible vegetable oil.