7种贵州名优绿茶品质化学成分分析

摘 要: 目的 比较7种贵州名优绿茶的品质化学成分。方法 对7种贵州名优绿茶进行感官审评和品质化学成分检测, 采用相关性分析和主成分分析(principal component analysis, PCA)对结果进行综合评价。结果 7种贵州名优绿茶感官品质综合得分由高到低排序为: 梵净山云雾茶>凤岗锌硒茶>绿宝石>贵定云雾茶>都匀毛尖>湄潭翠芽=石阡苔茶; 7种名优绿茶品质化学成分的总灰分含量为4.58%~4.98%, 茶多酚含量为15.59%~23.80%, 氨基酸含量为2.04%~4.93%, 咖啡碱含量为2.66%~3.83%, 可溶性糖含量为2.04%~5.07%, 水浸出物含量为41.23%~45.10%。相关性分析结果显示, 共10对指标间存在显著相关关系, 其中水浸出物与茶多酚极显著正相关(P<0.01), 与滋味显著负相关(P<0.05); 氨基酸与茶多酚极显著负相关(P<0.01), 与灰分显著负相关(P<0.05), 与香气显著正相关(P<0.05); 茶多酚与灰分显著正相关(P<0.05), 与滋味极显著负相关(P<0.01); 可溶性糖与咖啡碱极显著负相关(P<0.01), 与滋味极显著正相关(P<0.01); 咖啡碱与滋味极显著负相关(P<0.01); 采用主成分分析法对7个茶样建立综合得分数学模型F=0.492F1+0.249F2, 综合得分由高到低依次是: 湄潭翠芽>贵定云雾茶>都匀毛尖>凤岗锌硒茶>石阡苔茶>绿宝石>梵净山云雾茶。结论 贵州名优绿茶品质化学成分含量丰富, 整体品质优良, 研究结果将为贵州名优绿茶的生产加工和品质提升提供一定的理论依据。

Analysis of quality chemical components of 7 kinds of famous green tea in Guizhou

Objective To compare the quality chemical components of 7 kinds of famous green tea in Guizhou. Methods Sensory evaluation and quality chemical composition detection of 7 kinds of Guizhou famous green tea were carried out, and the results were comprehensively evaluated by correlation analysis and principal component analysis (PCA). Results The comprehensive sensory evaluation scores of 7 kinds of Guizhou famous green tea ranked from high to low was as follows: Fanjingshan Clouds-mist tea>Fenggang Zinc-selenium tea>Emerald tea>Guiding Clouds-mist tea>Duyun Maojian tea>Meitan Cuiya tea=Shiqian Tai tea; the ranges in content of quality chemical composition were 4.58%?4.98% for total ash, 15.59%?23.80% for tea polyphenol, 2.04%?4.93% for amino acid, 2.66%?3.83% for caffeine, 2.04%?5.07% for soluble sugar and 41.23%?45.10% water extracts. The correlation analysis results showed that there was significant correlations between a total of 10 pairs of indicators, among which the water extracts content was extremely significantly positively correlated with tea polyphenol (P<0.01), and significantly negatively correlated with the taste (P<0.05); the content of amino acid was extremely significantly negatively correlated with tea polyphenol (P<0.01), and significantly negatively with total ash (P<0.05), and significantly positively with the aroma (P<0.05); the tea polyphenol content was significantly positively correlated with total ash (P<0.05), extremely significantly negatively correlated with the taste (P<0.01); the soluble sugar content was highly significantly negatively correlated with the caffeine content (P<0.01), and highly significantly positively correlated with the taste (P<0.01); the caffeine content was extremely significantly negatively correlated with the taste (P<0.01). The mathematical model of comprehensive score was established for the 7 kinds of tea samples by principal component analysis: F=0.492F1+0.249F2, and the comprehensive scores in descending order were as follows: Meitan Cuiya tea>Guiding Clouds-mist tea>Duyun Maojian tea>Fenggang Zinc-selenium tea>Shiqian Tai tea>Emerald tea>Fanjingshan Clouds-mist tea. Conclusion Guizhou famous green tea is rich in quality chemical composition, and the overall quality is excellent. The results of this study will provide some theoretical basis for the production, processing and quality improvement of green tea in Guizhou.