Dehydration can significantly extend the shelf life of dried carrots and still retain nutrition of provitamin A carotenoids.In vitro digestion model was used in this study to assess the effect of drying temperatures of heat pump and dietary fat on the bioaccessibility ofβ-carotene in carrots.Also,low-speed centrifugation was employed to obtainβ-carotene release rate in supernatant.Microfiltration was applied to obtainβ-carotene micellar rate in micelle phase.These assays were used as indicators to assess the bioaccessibility of theβ-carotene.Despite higher drying temperatures had a negative effect on the retention rate ofβ-carotene in carrots,it showed a positive impact on the micellar rate.In addition,dietary fat significantly increased the release rate and micellar rate ofβ-carotene for both fresh carrots and dried carrot products,with the highest release rate and micellar rate obtained when 10%dietary fat was added.Therefore,the heat pump drying process and dietary fat can significantly improve the bioaccessibility ofβ-carotene in carrots,which may increase theβ-carotene bioavailability to human.
为分析预处理对百合热风干燥特性及其品质的影响,以新鲜百合为原料,探讨干燥温度、漂烫时间、漂烫温度对百合干燥产品有效水分扩散系数、干燥活化能、总酚与干基的质量比、总黄酮与干基的质量比、色泽和微观结构的影响。研究结果表明:干燥温度、漂烫时间和漂烫温度的增加可提高干燥速率,缩短干燥时间。百合在热风干燥过程中的有效水分扩散系数为0.51×10^(-10)~4.57×10^(-10)m^2/s,并根据阿伦尼乌斯公式,计算出未经处理和经100℃漂烫45 s的百合的干燥活化能分别为86.91 k J/mol和41.38 k J/mol。总酚与干基的质量比和总黄酮与干基的质量比随着漂烫时间及漂烫温度的升高而下降。漂烫时间为45 s、漂烫温度为100℃时,能有效改善干燥产品的色泽,与未处理样品相比,表面皱缩严重。百合最适宜的漂烫条件为漂烫温度100℃,漂烫时间45 s。
