微波、热风干燥对橙皮干燥特性及其品质影响的比较

Effects of Microwave and Hot-air Drying on Characteristics and Quality of Orange Skin

采用热风干燥,微波干燥两种干燥方法对橙皮进行干燥。从干燥速率、温度分布、持水力、吸脂性和外形5个方面对橙皮的干燥特性进行研究,并对处理后样品的品质进行比较。结果表明:干燥至相同的水分含量所需时间长短为:热风干燥>微波干燥;热风干燥温度分布均匀,微波干燥中心温度高于边缘温度;微波功率和热风温度对橙皮持水力、吸脂性和外形影响明显;低热风温度和微波功率能得到较好的持水力和吸脂性,热风温度越高,橙皮干样质构越不均匀,边缘越卷,微波功率越高,成品越不均匀,收缩越大。

Microwave treatment and hot-air treatment were separately applied to the drying of orange skin. The drying rate, temperature distribution, water-holding capacity, fat-absorption capacity, and appearance of orange skin dried by both drying methods were investigated. Meanwhile, effects of both drying methods on quality of treated samples were also compared. Results indicated that less time consumption was required to achieve the same water content in treated samples using microwave drying. In addition, microwave drying provided higher temperature in the center and lower temperature in the edge of the samples; in contrast, hot-air drying provided the even temperature distribution in the samples. Significant effects on water- holding capacity, fat-absorption capacity and appearance of treated samples using both drying methods were also observed. Better water-holding capacity and fat-absorption capacity were revealed in the samples treated by lower hot-air temperature or lower microwave power. The uneven texture and quality of the treated samples could be resulted from higher hot-air temperature and stronger microwave power.