不同季节信阳毛尖茶主要生化成分及其矿质元素差异性分析

目的 基于不同季节信阳毛尖茶的生化成分和矿质元素，探究多元统计分析方法对不同季节信阳毛尖茶的有效区分。方法 采用高效液相色谱法等化学方法对64种信阳毛尖茶主要生化成分及其矿质元素进行检测分析，结合正交矫正偏最小二乘法判别分析获取不同季节茶样的组间差异。结果 研究结果表明游离氨基酸、黄酮类物质、水溶性碳水化合物、非酯型儿茶素、表儿茶素(epicatechin，EC)、表没食子儿茶素(epigallocatechin，EGC)、没食子酸(gallic acid，GA)及矿质元素均存在季节性显著差异。判别分析可将信阳毛尖春茶和夏秋茶明显区分，并鉴定出黄酮类物质、游离氨基酸、GA、儿茶素(catechin，C)、EC、EGC、Mg和Zn 8种判别不同季节信阳毛尖茶的重要差异化合物。热图分析结果进一步证实，茶多酚、游离氨基酸、C、表儿茶素没食子酸酯(epicatechin gallate，ECG)和GA等物质主要在春茶中积累，黄酮类物质、EGC、表没食子儿茶素没食子酸酯(epigallocatechin gallate，EGCG)、Mg、Fe、Zn和Se等物质主要在夏秋茶上积累。结论 本研究鉴别了不同季节信阳毛尖茶的特征性差异化合物，为信阳毛尖茶的季节识别提供理论基础。

Analysis on the difference of main biochemical components and mineral elements of Xinyang Maojian tea harvested in different seasons

Objective To explore the effective discrimination of Xinyang Maojian tea harvested in different seasons by multivariate statistical analysis based on its biochemical components and mineral elements. Methods The main biochemical components and mineral elements of 64 kinds of Xinyang Maojian tea were analyzed by chemical methods such as High-performance liquid chromatography analysis, the intergroup differences of tea samples harvested in different seasons were obtained by orthogonal corrected partial least squares discriminant analysis. Results The results showed that there were significant seasonal differences in free amino acids, flavonoids, water-soluble carbohydrates, non-ester catechins, epicatechin(EC), epigallocatechin(EGC), gallic acid(GA) and mineral elements. The discriminant analysis could clearly distinguish Xinyang Maojian spring tea from summer-autumn tea, and flavones, free amino acids, GA, catechin(C), EC, EGC, Mg and Zn were identified as important compounds for distinguishing Xinyang Maojian tea harvested in different seasons. The results of heatmap analysis further confirmed that tea polyphenols, free amino acids, C, epicatechin gallate(ECG) and GA were mainly accumulated in spring tea, flavonoids, EGC, epigallocatechin gallate(EGCG), Mg, Fe, Zn and Se were mainly accumulated in summer-autumn tea. Conclusion The characteristic differential compounds of Xinyang Maojian tea were identified, which provided a theoretical basis for the seasonal identification of Xinyang Maojian tea.