有机成分与元素分析相结合鉴别6种中国名茶

利用有机成分与元素分析相结合,建立6种中国名茶的鉴别方法。通过原产地购买67份不同产地的茶叶,包括绿茶(杭州龙井、苏州碧螺春、黄山毛峰、庐山云雾)和乌龙茶(武夷岩茶、安溪铁观音),利用电感耦合等离子体-原子发射光谱测定茶叶中K、Ca、Mg、Al、Mn、Fe、Zn、Rb、Ti 9种元素,利用电感耦合等离子体-质谱法测定Pb、As、Cd、Cr、V、Ni、Co、Cu、Sr、Cs、Ba、Se 12种元素,利用超高效液相色谱测定茶叶中10种有机成分。通过偏最小二乘变量筛选法分别建立6种中国名茶的元素判别模型和有机成分判别模型,并设定已知茶叶样本的确证及未知茶叶样本的溯源流程。实际样品检测结果表明,6种中国名茶分类效果较好,通过2种模型交叉验证可有效减少结果误判。

Discrimination of 6 Kinds of Chinese Tea by Combination of Organic Components and Multielement Analysis

A discrimination method for 6 kinds of Chinese famous tea by combination of organic components and
multielement analysis was established. Totally 67 different tea samples from their places of origin were collected, including
green tea (Huangshan Maofeng, West Lake Longjing, Biluochun and Lushan Fragrant) and oolong tea (Wuyi Rock Tea,
Ti Kuan Yin). The concentrations of 9 elements (K, Ca, Mg, Al, Mn, Fe, Zn, Rb and Ti) were determined by ICP-AES, 12
elements (Pb, As, Cd, Cr, V, Ni, Co, Cu, Sr, Cs, Ba and Se) by ICP-MS, and 10 organic compounds by UPLC. Partial least
squares variable selection method was applied in the establishment of the discrimination models for elements and organic
components, and a tracing procedure was set up for the confirmation of the known and unknown tea samples. The analysis
of real samples showed that the 6 kinds of Chinese famous tea were well discriminated and misjudgment was reduced
effectively by cross validation of the two models.