为改善辣椒干燥品质及节能降耗,采用热泵-微波联合干燥辣椒。首先探讨不同热泵温度、微波功率和转换点含水率3个因素对辣椒含水率和色差的影响,以色差和含水率为初步考察指标,选择3因素的适宜范围。在此基础上,选择以上3因素为试验因素进行响应面法Box-Behnken中心组合试验设计,分别测定干制辣椒的辣椒碱、二氢辣椒碱、辣椒红素、色差、单位能耗和单位耗时,按照各指标的最大值为参照值进行归一化,赋予不同的权重系数进行多指标综合评分,通过响应面法对其优化,得到辣椒热泵-微波联合干燥的最佳工艺参数:热泵温度50.38 ℃、转换点含水率50.39%、微波功率286.14 W,最高综合评分为0.488 604。验证结果与试验结果相对误差<4%,优化结果可靠。
In order to improve the drying quality of chili and reduce energy consumption, we use heat pump-microwave drying chili. First of all, the effects of different heat pump temperature, microwave power and conversion point moisture content on the moisture content and color difference of pepper were discussed. The color difference and water content were taken as the primary indexes of investigation, and the appropriate range of three factors was selected. On this basis, the above three factors were selected as the experimental factor to get on Response surface method Box-Behnken center combination experimental design. Capsanthin, capsaicin, dihydro capsaicin, color difference, unit energy consumption and unit time-consuming were separately measured. The maximum of each index was normalized by the reference value, and different weight coefficients were given for the multi-index comprehensive score, and then optimized by response surface methodology. The optimal process parameters of chili heat pump-microwave combined drying were as follows: heat pump temperature was 50.38 ℃, conversion point moisture content was 50.39%, microwave power was 286.14 W and the highest comprehensive score was 0.488 604. The relative error between the verification result and the test result was less than 4%, which proved that the optimization result was reliable.