不同干燥方式对速溶青砖茶中儿茶素含量及香气成分的影响

以湖北特色青砖茶为原料,经浸提、过滤、浓缩之后,研究热风干燥、真空冷冻干燥、离心喷雾干燥对速溶青砖茶中儿茶素含量及香气成分的影响。HPLC检测分析结果显示,速溶青砖茶粉相比原料,儿茶素及咖啡碱成分都有明显增加,其中真空冷冻干燥和离心喷雾干燥粉中儿茶素含量差异不大,但都明显高于热风干燥粉;GA、GC、EGC、C、Caf、EGCG和EC七种有效成分,真空冷冻干燥粉中含量较高;GCG、ECG和CG三种有效成分,离心喷雾干燥粉中含量较高。GC-MS检测分析结果显示,青砖茶原料、热风干燥粉、离心喷雾干燥粉和真空冷冻干燥粉各鉴定出33、19、39和29种挥发性香气成分,离心喷雾干燥对于速溶茶中的香气成分有更好的保留和增加效果,并且减少了部分对风味有反作用的物质。

Effects of Different Drying Methods on the Content of Catechins and Aroma Components of Instant Qingzhuan Tea Powder

Taking Qingzhuan tea as raw material, after extracting, filtrating and concentrating, the effects of different drying methods on the content of catechin and aroma components of instant Qingzhuan tea powder were studied. HPLC analysis re-sults showed that,compared to raw materials,catechins and caffeine components in instant tea powder increased significantly, especially the difference of the catechin content between vacuum freeze drying powder and centrifugal spray dryingpowder was not significant, but significantly higher than that of hot air drying powder. The content of seven effective components in-cluding GA, GC, EGC, C, Caf, EGCG and EC in vacuum freeze drying powder was high. The content of three effective components including GCG, ECG and CG in centrifugal spray drying powder was high. GC-MS analysis results showed that, Qingzhuan tea and hot air drying powder, centrifugalspray drying powder and vacuumfreezedrying powder of each identified 33, 19, 39 and 29 kinds of volatile aroma components, aroma components for centrifugalspray drying of instant tea has bet-ter retention and increase the effect, and reduce some of the flavor of a reaction substance.