不同海拔云南大叶种晒青茶感官品质及主要生化成分差异分析

Analysis of the Difference in Sensory Quality and Main Biochemical Components of Yunnan Large Leaf Sun-dried Green Tea at Different Altitudes

为探究海拔对云南大叶种晒青茶品质的影响,以无量山不同海拔云南大叶种晒青茶为研究对象,采用感官审评、高效液相色谱法、同时蒸馏萃取/气相色谱-质谱法结合主成分分析、正交偏最小二乘法等技术和方法,对其感官品质、主要生化指标、挥发性成分进行比较分析。结果表明,海拔1400~1800 m的晒青茶(H1)茶汤色泽更浅,亮度更高;海拔1800~2000 m的晒青茶(H2)涩味减轻,鲜爽味增强;H1与H2主要生化成分和挥发性成分存在显著差异,H1水浸出物、茶多酚、儿茶素总量、没食子酸、酚氨比、没食子儿茶素没食子酸酯(GCG)、表儿茶素没食子酸酯(ECG)含量显著高于H2,游离氨基酸总量、茶氨酸、天冬氨酸、谷氨酸、甘氨酸、赖氨酸、异亮氨酸、苯丙氨酸含量显著低于H2;另外,H1与H2共有17种挥发性成分存在显著差异,分别为正癸酸、叶绿醇、壬醛、青叶醛、水芹醛、己酸乙酯、脱氢芳樟醇、邻苯二甲酸二异丁酯、1-己醇、反式橙花叔醇、法尼基丙酮、大马士酮、香叶醇、4-甲基-3戊烯-2-酮、亚麻酸甲酯、邻苯二甲酸二正丁酯、橙花醇。本研究结果可为海拔影响茶叶品质的研究提供理论依据。

In order to understand the quality differences of Yunnan large leaf sun-dried green tea at different altitudes,the sensory evaluation,high performance liquid chromatography,simultaneous distillation extraction/gas chromatography-mass spectrometry combined with principal component analysis,orthogonal partial least square-discriminant analysis and other techniques and methods were used to compare the sensory quality,major biochemical components and volatile components of Yunnan large leaf sun-dried green tea at different altitudes in Wuliang Mountain.The results showed that the soup color of sun-dried green tea(H1)from 1400 m to 1800 m was lighter and brighter;the astringency of sun-blue tea(H2)from 1800 m to 2000 m was reduced and the umami taste was enhanced.The main biochemical and volatile components of H1 and H2 were significantly different;the contents of water extract,tea polyphenols,total catechins,gallic acid,phenol to ammonia ratio,GCG,ECG of H1 were significantly higher than those in H2;the contents of free amino acids,theanine,aspartic acid,glutamic acid,glycine,lysine,isoleucine and phenylalanine were significantly lower than those in H2.In addition,there were 17 volatile components in H1 and H2 with significant differences,namely,n-decanoic acid,chlorophyll alcohol,nonanal,trans-2-hexenal,heptanal,ethyl caproate,dehydrolinalool,diisobutyl phthalate,1-hexanol,trans-nerolidol,farnesyl acetone,damascenone,geraniol,4-methyl-3-penten-2-one,methyl linolenate,di-n-butyl phthalate,and nerolidol.This study will provide some reference value for the research on the effect of altitude on tea quality.