不同干燥方式对杨梅果干营养品质及抗氧化性影响

摘要

探讨新鲜杨梅果实在不同干燥过程中的特性,分析不同工艺条件对杨梅的营养物质、色泽、产品品质及抗氧化性的影响.结果表明,与鼓风干燥方式相比,采用热泵方式杨梅的干燥时间为16.5 h,比鼓风干燥缩短2.5 h,干燥速率较高,时间较短,并且热泵干燥后杨梅果实中总糖含量及多酚、花色苷、VC等营养成分含量较高.而采用不同干燥方式的杨梅干总酸含量无显著差异,鼓风干燥后杨梅的色泽变化较热泵干燥明显,复水比低于热泵干燥.测定杨梅干对羟基自由基(·OH)及1,1-二苯基-2-三硝基苯肼自由基(DPPH·)的清除作用来检验其抗氧化能力,结果表明采用热泵干燥的杨梅干抗氧化能力显著高于鼓风干燥.综合比较,不同干燥方式对杨梅营养与品质特性的影响差异较大,热泵干燥杨梅营养成分与抗氧化活性损失较小.%The characteristics of bayberry fruit in different drying processes were discussed in this paper. The effects of different process conditions on nutrient, color and product quality of bayberry were analyzed. The re-sults showed that fruit drying time by heat pump drying method (16.5 h) was shorter 2.5 h than blast drying method. Compared with blast drying method, heat pump drying method had higher drying rate. The contents of total sugar, polyphenols, anthcyanins and VC in bayberry fruit were higher by heat pump drying. However, there was no significant difference on total acid content in bayberry fruit under different drying methods. Blast drying fruit exhibited more significant color changethan heat pump drying fruit, and blast drying fruit had lower rehydration ratio than heat pump drying fruit. Scavenging abilities of DPPH radical and hydroxyl radical(·OH) were measured to determine antioxidant activity of dried bayberries. The results showed that heat pump drying fruit presented higher antioxidant activity than blast drying fruit. The results indicated that there were significant differences in nutrition and physical properties of bayberry among different drying methods. The best nutrition and antioxidant activity were found in bayberry dried by heat pump drying method.