不同海拔政和白茶品质差异分析

Quality Differences of Zhenghe White Tea from Different Altitudes

以不同海拔茶树鲜叶及成品茶为材料,采用感官审评和生化成分测定,结合多元统计分析探究海拔高度对政和白茶品质的影响。感官审评结果表明:不同海拔政和白茶品质有显著差异,中、高海拔白茶滋味清鲜、醇爽,香气清纯,低海拔白茶滋味醇厚,花香显。偏最小二乘判别分析结果表明,可溶性糖、咖啡碱、3-蒈烯、马鞭草烯醇、萜品油烯、顺-2-戊烯醇、2-乙基呋喃和顺-2-己烯-1-醇是区分不同海拔茶树鲜叶关键的差异成分,其中可溶性糖、顺-2-己烯-1醇、顺-2-戊烯醇等差异化合物在中、高海拔样品中含量较高,咖啡碱、3-蒈烯、马鞭草烯醇和萜品油烯等挥发性成分在低海拔样品中含量普遍较高。可溶性糖、游离氨基酸、萜品油烯、马鞭草烯醇、2-乙基呋喃、2-甲基丁醛、苯乙醇和3-蒈烯是区分不同海拔成品茶关键的差异成分,其中可溶性糖、游离氨基酸在高海拔成品茶含量普遍较高;萜品油烯、马鞭草烯醇、苯乙醇和3-蒈烯等挥发性成分在中、低海拔样品中含量较高,且在高海拔样品中含量普遍较低。进一步结合香气活度值分析,2-甲基丁醛、3-蒈烯和萜品油烯可作为鉴别不同海拔白茶的特征挥发性成分。本研究将为进一步探究不同海拔茶叶风味品质特征提供一定参考依据。

To explore the effect of growing altitude on the quality of Zhenghe white tea,the sensory quality and biochemical composition of tea leaves and Zhenghe white tea from different altitudes were evaluated,and multivariate statistical analysis was applied to the obtained data.The results of sensory evaluation showed that there were significant differences in the quality of white tea from different altitudes.The mid-and high-altitude white tea tasted fresh,mellow and clean with a clean and pure aroma,while the low-altitude white tea tasted mellow and thick with a floral aroma.Partial least squares discriminant analysis(PLS-DA)showed that soluble sugars,caffeine,3-carene,verbenenol,terpene oleene,cis-2-pentenol,2-ethylfuran and cis-2-hexene-1-alcohol were the key components to distinguish fresh tea leaves from different altitudes.The contents of soluble sugar,cis-2-hexene-1 alcohol and cis-2-pentenol were higher in the mid-and high-altitude samples,while the contents of volatile components such as caffeine,3-carene,verbenol and terpinolene were higher in the low-altitude samples.Soluble sugar,free amino acid,terpinolene,verbenol,2-ethyl furan,2-methylbutyraldehyde,2-phenylethanol and 3-carene were the key components to distinguish white tea from different altitudes.The contents of soluble sugar and free amino acid were higher in the high-altitude white tea,and the contents of volatile components such as terpinolene,verbenol,phenyl ethanol and 3-carene were higher in the mid-and low-altitude samples,but low in the high-altitude samples.According to odor activity value(OAV)analysis,2-methyl butyl aldehyde,3-carene and terpinolene could be used as the characteristic volatile components to identify white tea samples from different altitudes.The results of this study will provide a reference for further exploring the flavor quality of tea from different altitudes.