草莓切片微波真空干燥特性及干燥品质研究(英文)

Microwave-vacuum Drying Characteristics and Drying Quality of Strawberry Slices

提高水果干燥效率、干制品质量和降低干燥能耗,对草莓切片进行微波真空干燥,研究草莓切片微波真空干燥特性及其干后品质。通过二次回归正交试验,建立各指标与干燥功率、样品厚度及干燥室压力等因素间的回归数学模型,分析草莓切片微波干燥特性,讨论干燥功率、样品厚度及干燥室压力等因素对干制品的复水率、VC保存率和干燥能耗的影响。结果表明:随着样品厚度与压力的降低和干燥功率的增加,干燥速率增加;随着样品厚度的增加和干燥功率与压力的降低,复水率和VC保存率增加;随着样品厚度与干燥功率的增加和压力的降低,干燥能耗减少。最后,利用多目标非线性优化方法,确定了草莓切片微波真空干燥最优工艺参数,即微波功率6.18W/g、切片厚度5.05mm、干燥室压力55.19Pa。

To improve the drying productivity and the quality of dried fruits, and to decrease the drying energy consumption, experiments were conducted to study the microwave-vacuum drying characteristics of strawberry slices and the quality of their dried products. The quadratic regression orthogonal design method was employed to establish regression mathematical models describing the relationships between the rehydration ratio of dried strawberry slices, vitamin C retention ratio or the energy consumption durinzg drying and drying power, sample thickness and drying chamber pressure. The effects of these variables on these functions were dealt with. Decreasing sample thickness and drying chamber pressure and increasing drying power could individually result in a higher dehydraation rate. The rehydration ratio of dried strawberry slices and vitamin C retention ratio became both higher, with increasing sample thickness or decreasing drying chamber pressure. The energy consumption during drying tended downward, as sample thickness and drying power increased or drying chamber pressure increased. The optimum process parameters for drying strawberry slices were determined by multivariable nonlinear optimization method as follows： drying power, 6.18 W/g; sample thickness, 5.05 mm; and drying chamber pressure, 55.19 Pa.