罗非鱼片热泵-微波联合干燥工艺

Combined drying technology of tilapia fillets using heat pump and microwave

采用响应面分析法优化罗非鱼片热泵-微波联合干燥工艺参数。分别以干燥能耗和产品复水率为试验指标,以热泵干燥温度、转换点含水率、微波功率3因素为自变量,设计3因素3水平组合响应面分析试验,得出干燥能耗和产品复水率随热泵干燥温度、联合干燥转换点含水率和微波干燥功率变化的回归模型。三组验证试验的试验值与相应模型预测值的误差绝对值均小于5%。基于能耗最小的优化参数为:热泵干燥温度为34.34℃,转换点含水率为42.12%,微波功率为131.69 W;基于复水率最大的优化参数为:热泵干燥温度为33.87℃,转换点含水率为30%,微波功率为201.43 W。以热泵-微波联合干燥工艺参数组合(干燥温度为35℃,转换点含水率为39%,微波干燥功率取微波炉功率档252 W)进行试验,并与相同工况(温度和风速)热泵干燥试验值进行比较,结果表明,热泵-微波联合干燥时间比热泵干燥时间缩短了2/3;热泵-微波联合干燥罗非鱼片复水40 min,复水率达到57.40%,比热泵干燥的复水率(39.16%)增加46.5%。该文为热泵—微波联合干燥罗非鱼提供参考。

The technology of heat pump combined with microwave for drying Tilapia fillets was optimized by response surface method.Taking drying energy consumption and rehydration rate as dependent variable,the models were obtained by using response surface analysis of the three factors of temperature of heat pump drying,water content rate and power of microwave drying at three levels.The results of test and verification showed that all of the error between the value of models and the value of experiments was less than 5%.Base on the minimum of energy consumption,the optimized technology parameters were that the temperature of heat pump drying was 34.34℃,the water content rate at transformation point was 42.12% and the power of microwave drying was 131.69 W,respectively.Base on the maximum of rehydration rate,the optimized technology parameters were that the temperature of heat pump drying was 33.87℃,the water content rate at transformation point was 30% and the power of microwave drying was 201.43 W,respectively.Comparing the test result of heat pump combined with microwave at drying temperature of heat pump of 35℃,the water content rate at transformation point of 39% and microwave power of 252 W with that of heat pump drying test at same temperature and wind speed,it showed that the time of combination drying was shorter two-thirds than the heat pump drying.The rehydration rate of the optimized combination drying was 57.40%,and that of the heat pump drying was 39.16% at the same rehydration time of 40 min.The results also showed the rehydration rate of combined drying was increased by 46.5% compared with that of heat pump drying.The results can provide references for drying tilapia fillets of the combined heat pump with microwave drying technology.