中文摘要：

以红富士苹果作为实验材料，以氮气为干燥介质置换空气降低设备中氧体积分数，研究了温度、切片厚度、氧体积分数和风速对苹果片热泵干燥速率、三值、VC和总酚含量等指标的影响，正交试验结果表明：最佳干燥工艺参数为干燥温度55℃、切片厚度5mm、氧体积分数5％，干燥后苹果片水分含量为5．83％，三值为83．01，VC含量为3．68mg／100g，总酚含量为68．26mg／100g。

英文摘要：

This study was conducted to dry fresh-cut red Fuji apple slices using nitrogen as drying medium to reduce the oxygen concentration in a heat pump dryer. The influences of drying temperature, slice thickness, oxygen concentration and air speed on drying rate, brightness, vitamin C （VC） content and total phenol content were investigated. The experiment results of orthogonal array design showed that the optimal drying parameters were as follows： temperature, 55 ℃; slice thickness, 5 mm; and oxygen volume fraction, 5%. The moisture content of apple slices dried under these conditions was 5.83%, brightness value 83.01, VC content 3.68 mg/100 g, and total phenol content 68.26 mg/100 g.