热风微波耦合干燥鲜枣的研究

Study on coupled hot air and microwave drying of fresh jujube

为获得干燥速率快、品质高、能耗小的鲜果干燥技术,以鲜枣为试材,采用自行设计的热风微波耦合干燥机对鲜枣进行了热风微波耦合干燥工艺研究。以微波功率、热风温度、载重为实验因素,研究其对枣干燥速率的影响;利用极差分析各因素对枣干燥速度、复水比和维生素C含量的影响。结果表明,耦合干燥各因素对干燥速率及干燥产品质量均有明显影响,影响各指标的主次顺序为微波功率>载重>热风温度。因此,热风微波耦合干燥相比微波干燥和热风干燥,可以获得干燥速率快、VC含量高、复水性能良好的优质产品。

For drying of fruits and vegetables in high speed,quality and low energy,the coupled hot air and microwave dryer was designed,and drying was conducted with fresh jujubes as test materials. Microwave power,hot air temperatures and surface load were chosen as three factors for analysis drying process. Range analysis was used to discuss the influnce of factors on drying speed,Vc content and rehydration rate. The experimental results showed that each factor to both drying rate and dry product quality had obvious influence. Microwave power had the most important effect,surface load followed,and the hot air temperature had the least effect on drying indexes. Therefore,compared microwave drying and hot air drying,coupled hot air and microwave drying could improve drying speed greatly. Good quality products with high Vc content and rehydration rate could be also gained.