香菇中短波红外干燥工艺优化

以香菇为原料，采用响应面法优化香菇中短波红外干燥工艺。在单因素试验基础上，根据Box-Behnken试验设计原理，选取干燥温度、切片厚度和辐照距离进行三因素三水平试验，分析干燥温度、切片厚度和辐照距离对香菇片色泽L、复水性、硬度、氨基酸及总糖含量的影响及因素间交互作用对指标的影响，并建立各指标的二次回归方程，确定中短波红外干燥香菇片的最佳工艺条件。结果表明：干燥温度是影响香菇干燥品质的主要因素，随着温度的升高香菇色泽L、复水比、硬度、氨基酸及总糖含量下降；其次是切片厚度，随着切片厚度增加香菇色泽L、复水比、总糖含量减少，而氨基酸含量先增后减。干燥香菇的最佳工艺条件为：干燥温度55 ℃、切片厚度4.5 mm、辐照距离120 mm。在此条件下得到香菇色泽L为58.56、复水比为5.32、硬度为495.63 g、氨基酸含量为818.12 mg/100 g、总糖含量为281.37 mg/g，与理论预测值无显著性差异。

Optimization of Medium- and Short-Wave Infrared Radiation Drying Process for Shiitake Mushroom

The response surface methodology was used to optimize the drying conditions for shiitake mushroom using
infrared radiation. Using Box-Behnken design, a quadratic regression model was established indicating the effects of drying
temperature, slice thickness and radiation distance at 3 levels each on color L value, rehydration ratio, hardness, amino acids
and total sugar contents. Results showed that drying temperature was the major factor affecting the quality of dried shiitake
mushroom, followed by slice thickness. Color L, rehydration ratio, hardness, amino acids and total sugar content of shiitake
mushroom decreased with increasing temperature. A decrease in color L, rehydration ratio, and total sugar content was
observed with increasing slice thickness, yet amino acid content initially increased and then declined. The optimum drying
conditions were determined as follows: drying temperature, 55 ℃; slice thickness, 4.5 mm; and radiation distance, 120 mm.
Under these conditions, color L, rehydration ratio, amino acid content and total sugar content were measured to be 58.56, 5.32,
495.63 g, 818.12 mg/100 g and 281.37 mg/g, respectively, which were in close agreement with the values predicted by the
developed model.