Pretreatments of either water blanching or NaCl immersion and airborne ultrasound-assisted air drying were combined to dehydrate apple slices. The drying time was found to be reduced by 1.6–69.0% compared with air drying without any pretreatment and sonication. Meanwhile, it was found that sequential water blanching coupled with air drying with sonication gave the shortest drying time. A modified diffusional model incorporating temperature-dependent moisture diffusivity (D_eff) could simulate the apple drying process well. Water blanching pretreatment and airborne sonication were found to lower the activation energy required for the enhancement of moisture diffusive ability, and intensify water exchange on apple surface to speed up the drying process. Both water blanching and NaCl immersion significantly increased the amounts of procyanidin B2 in dehydrated apple slices. However, airborne sonication promoted the loss of procyanidin B2 in apple slices with pretreatments during air drying. In addition, sonication had no obvious influences on apple PPO activity and individual organic acids throughout drying. Overall, the sequential NaCl immersion pretreatment (or water blanching pretreatment) and drying with airborne sonication are effective to improve the quality of dried apple slices.

将水烫或氯化钠浸泡的预处理和空气超声辅助空气干燥相结合，使苹果切片脱水。与没有任何预处理和超声处理的空气干燥相比，干燥时间减少了 1.6-69.0%。同时，发现连续水烫与超声风干相结合的干燥时间最短。一种改进的扩散模型，包含与温度相关的水分扩散系数 ( D _eff) 可以很好地模拟苹果的干燥过程。研究发现，水烫预处理和空气声波处理降低了增强水分扩散能力所需的活化能，并加强了苹果表面的水分交换，加快了干燥过程。水烫和 NaCl 浸泡均显着增加了脱水苹果切片中原花青素 B2 的含量。然而，在空气干燥过程中，空气声波处理会促进经过预处理的苹果切片中原花青素 B2 的损失。此外，在整个干燥过程中，超声处理对苹果 PPO 活性和单个有机酸没有明显影响。总体而言，连续 NaCl 浸渍预处理（或水烫预处理）和空气声波干燥可有效提高苹果干切片的质量。