适当的干燥方法对于生产高质量的杏干至关重要。在这项研究中,四种干燥方法的效果,热风干燥(HAD),红外干燥(IRD),脉冲真空干燥(PVD),和真空冷冻干燥(VFD),对杏片的干燥动力学和物理营养特性进行了评价。PVD需要最短的时间(16.25h),其次是IRD(17.54小时),HAD(21.39小时),和VFD(34.64小时)。VFD导致杏片的最佳质量,具有最小的色差(ΔE=13.64),最低水分活度(0.312±0.015)和褐变度(0.35),最高色彩饱和度(62.84),最低硬度(8.35±0.47N)和收缩率(9.13±0.65%),补液能力最强(3.58±0.11g/g),良好的微观结构,和高营养保留率(抗坏血酸含量:53.31±0.58mg/100g,总酚含量:12.64±0.50mgGAE/g,和类胡萝卜素含量:24.23±0.58mg/100g)和抗氧化活性(DPPH:21.10±0.99mmolTrolox/g和FRAP:34.10±0.81mmolTrolox/g)。PVD处理的杏片质量次优,HAD处理的杏片质量最差。然而,VFD所需的能耗相对较高,而PVD的要求较低。本研究结果为杏干的大规模工业化生产提供了科学依据。
An appropriate drying method is crucial for producing high-quality dried apricots. In this study, the effects of four drying methods, hot air drying (HAD), infrared drying (IRD), pulse vacuum drying (PVD), and vacuum freeze-drying (VFD), on the drying kinetics and physical and nutritional characteristics of
apricot slices were evaluated. PVD required the shortest time (16.25 h), followed by IRD (17.54 h), HAD (21.39 h), and VFD (34.64 h). VFD resulted in the best quality of
apricot slices, with the smallest color difference (ΔE = 13.64), lowest water activity (0.312 ± 0.015) and browning degree (0.35), highest color saturation (62.84), lowest hardness (8.35 ± 0.47 N) and shrinkage (9.13 ± 0.65%), strongest rehydration ability (3.58 ± 0.11 g/g), a good microstructure, and high nutrient-retention rates (ascorbic acid content: 53.31 ± 0.58 mg/100 g, total phenolic content: 12.64 ± 0.50 mg GAE/g, and carotenoid content: 24.23 ± 0.58 mg/100 g) and antioxidant activity (DPPH: 21.10 ± 0.99 mmol Trolox/g and FRAP: 34.10 ± 0.81 mmol Trolox/g). The quality of PVD-treated
apricot slices was second-best, and the quality of HAD-treated
apricot slices was the worst. However, the energy consumption required for VFD was relatively high, while that required for PVD was lower. The results of this study provide a scientific basis for the large-scale industrial production of dried apricots.