挤压膨化对铁观音茶梗滋味和香气成分的影响

为综合利用茶叶加工厂废弃的茶梗，采用挤压膨化技术对铁观音茶梗进行处理，并分析挤压膨化前后铁观音茶梗的香气和滋味成分的变化。试验结果表明：膨化后的茶梗中的灰分、咖啡碱、茶多酚含量均低于原茶梗，水浸出物的含量相当，碳水化合物含量略高于原茶梗。膨化茶梗共鉴定出48种香气成分，比原茶梗少5种。与原茶梗相比，膨化茶梗的苯乙醇、吲哚含量分别增加5.28%、3.69%；橙花椒醇减少0.15%。可以认为铁观音茶梗在挤压膨化前后香型发生了一定的转变，膨化后茶梗口感要明显好于膨化前，可为茶梗的利用提供一种新方法。

Effects of extruding processing of Tieguanyin tea stem on its flavor and aroma components

For the comprehensive utilization tea stalk which was always discarded by tea processing factories, the Tieguanyin tea stalk was processed by extrusion technology. The aroma and taste components in the Tieguanyin tea stalk before and after extrusion were determined. Results revealed that the decreases in the contents of taste components such as ash, caffeine and tea polyphenols were much noted after extrusion than original tea stalk. The water extracts were the same lever while the content of carbohydrate increased. 48 kinds of aroma ingredients in tea stalk after extrusion were identified, 5 kinds less than those in original tea stalk. There were 5.28% phenethyl alcohol and 3.69% indole more in the expanding tea stalk than those in the original tea stalk, but there was 0.15% nerolidol less in expanding tea stalk.