不同杀青方式对铁皮石斛叶茶的活性成分及抗氧化活性的影响

Effects of Different De-Enzyme Techniques on Functional Components and Antioxidant Activity of Dendrobium Officinale Leaf Tea

目的:寻找适当且经济利用铁皮石斛叶的途径。方法:以铁皮石斛鲜叶为试验材料,采用炒青、漂烫、蒸制、微波和烘青5种不同的杀青方式制备叶茶,分析叶和不同杀青方式叶茶的活性成分及抗氧化活性。结果:未经杀青的铁皮石斛叶多糖含量高于杀青处理的叶茶,为14.74%,黄酮(1.40%)和多酚(12.61%)的含量低于杀青处理的叶茶,除漂烫杀青外,其他处理生物碱含量无显著差异;5种不同杀青方式的叶茶中,微波杀青和烘青有效成分含量显著高于其他杀青方式,多糖含量分别为14.01%和14.25%,黄酮含量分别为1.60%和1.59%,总多酚含量分别为15.78%和15.22%,花色苷含量分别为0.031%和0.030%;烘制杀青的感官评分最高;未杀青铁皮石斛叶清除DPPH和ABTS自由基能力及FRAP还原力均显著小于杀青处理叶茶,说明其抗氧化活性显著低于杀青处理的叶茶;各杀青方式中,微波杀青和烘青叶茶抗氧化活性显著高于其他杀青方式叶茶。因此,对铁皮石斛鲜叶进行杀青是一种有效保留其活性成分的加工方法,尤其是微波杀青和105℃高温烘青处理叶茶的活性成分含量最高、抗氧化活性最强。结论:研究表明铁皮石斛叶具有开发成健康茶饮和天然抗氧化剂的潜力,是一种经济前景广阔的植物材料,铁皮石斛叶茶的实际生产中可采用微波和105℃高温烘制的杀青工艺。

Objective:To provide guidance for the comprehensive development and utilization of Dendrobium Officinale(D.Officinal)leaves.Methods:D.Officinale fresh leaves were processed into leaf tea by different de-enzyme techniques,including pan-fired fixing,scalding fixing,steam fixing,microwave fixing and baking fixing.This study evaluated the leaves and D.Officinale leaf tea based on effective ingredients and antioxidant activity.Results:The content of polysaccharides was leaves(14.47%)>leaf tea,The content of total flavonoids(1.40%)and total phenols(12.61%)in leaf tea was significandy higher than that in leaves,and the content of total alkaloids no significant difference except blanching fixing;The functional compoments content of leaf tea by mcrowave fixing and baking fixing were higher than those of the other three processes.The polyaccharide content was 14.01%and 14.25%,respectively.The flavonoid content was 1.60%and 1.59%,respectively;The total phenol content was 15.78%and 15.22%,respectively;and the anthocyanins content was 0.031%and 0.030%.The results of DPPH,ABTS,FRAP analyses all indicated that the leaf tea had a higher antioxidant capacity than leaves.Therefore,it is found that the de-enzyme techniques could help to retain active ingredients of D.Officinale fresh leaves,especially to microwave fixing and 105℃baking fixing.Conclusion:On the basis of the analysis,it finally concludes that D.Officinale fresh leaf is promising and econimical herbal plant with great potential for developing healthy tea product and natural antioxidant.