[关键词]
[摘要]
为了探究Weibull分布函数中各参数的影响因素及其在干燥中的应用,本试验以猕猴桃切片在不同的中短波红外干燥干燥温度(50、60、70、80 ℃)、干燥功率(675、1350、2025 W)条件下的干燥过程为研究对象,利用Weibull分布函数对其干燥动力学曲线进行模拟并分析。结果表明:Weibull分布函数能够很好地模拟猕猴桃切片的中短波红外干燥过程;尺度参数α与干燥温度和干燥功率均有关,并且随着干燥温度和红外功率的升高而降低;而干燥温度和红外功率对形状参数β的影响较小。通过计算求出干燥过程中的估算水分有效扩散系数,其值在1.06×10-7~3.51×10-7 m2/s范围内随着温度的升高而增大;通过阿伦尼乌斯方程计算出功率为675、1350和2025 W时,干燥活化能分别为32.55、27.02和28.07 kJ/mol。该研究为Weibull分布函数在猕猴桃中短波红外干燥技术的运用提供了技术依据。
[Key word]
[Abstract]
In this study, the kiwifruit was selected as raw material to investigate the effect of drying conditions on the parameters of Weibull distribution. The experiment was conducted at different levels of med-and short-wave infrared radiation drying temperature (50, 60, 70, 80 ℃) and infrared power (675, 1350, 2025 W). The result showed that the Weibull distribution function was good in simulating the process of med-and short-wave infrared radiation drying of kiwifruit slices. The scale parameter (α) was found to be related with the drying temperature and infrared power, and was decreased with increasing drying temperature and infrared power. However, the drying conditions had little influence on the shape parameter (β). The estimated moisture effective diffusivity (Dcal) of kiwifruit samples were calculated to be in the range from 1.061×10-7 to 3.51×10-7 m2/s, which increased with increasing drying temperature within the ranges tested. The activation energy determined from Arrhenius equation was 32.55, 27.02 and 28.07 kJ/mol at 675 W, 1350 W and 2025 W, respectively.
[中图分类号]
[基金项目]
公益性行业(农业)科研专项经费资助(201303073);国家“十二五”科技支撑计划课题“复合果蔬新产品创制与节能减排关键技术开发及示范”(2012BAD31B06)资助