Abstract:The effects of different drying techniques on the drying characteristics and quality of apple crisps were investigated. Hot air drying, mid-short wave infrared drying and pulsatile pressure differential flash drying were used to dry apple crisp slices, and the internal temperature, volume and water activity of apple crisp slices were tested by various drying techniques, and the effects of various drying techniques on color parameters and quality of apple crisp slices were tested and compared. The results showed that the L* value of hot air drying technology was 85.69, lower than 93.58 of medium-short wave infrared drying technology, higher than 81.45 of pulsatile differential pressure flash drying (p<0.05); the color difference comprehensive scores of hot air drying, medium-short wave infrared drying and pulsatile differential pressure flash drying were 20.35, 4.52 and 17.53, respectively (p<0.05); the vitamin C mass fraction, rehydration ratio and brittleness values of medium-short wave infrared drying were 2.98, 44.31, 9.05, respectively, higher than 2.71, 4.05 and 8.64 of hot air drying, lower than 3.26, 4.98 and 10.59 of pulsatile differential pressure flash drying (p<0.05). Comparing the three drying methods, it was found that the pulse pressure differential flash drying method had the greatest impact on the quality of apple crisp slices, the medium-short infrared drying method had the greatest impact on the color of apple crisp slices, and the medium-short wave infrared drying method had the greatest impact on the drying characteristics of apple crisp slices
