原子吸收光谱法测定比较5种不同品牌茶叶中微量元素含量

Determination and Comparision of Concentration of Trace Elements in 5 Different Brands of Tea by FAAS

摘要: 对市售茶叶崂山绿茶、茯茶、安溪铁观音、乌龙茶、茉莉茶王中微量元素Ca、Mg、Fe、Cu、Zn的含量进行考察.采用V(高氯酸)∶V(硝酸)=1∶4混酸消解的方法将样品在低温下消解,火焰原子吸收光谱法定量.实验测得5种茶叶中均含丰富的Ca、Mg，其中茯茶含Fe最多；崂山绿茶含Cu最多；安溪铁观音和崂山绿茶含Zn多.各元素工作曲线相关系数r>0.9948,加标回收率94.38%~105.00%，相对标准偏差在2.26%以下.实验方法快速、定量准确，测得各品牌茶叶中微量元素含量可为消费者提供参考.

Abstract: In this paper, the concentration of trace elements such as Ca, Mg , Fe ,Cu and Zn in Laoshan green tea, Fu tea, Anxi Tieguanyin tea , Wuloo tea and Moli tea were determined by the flame atomic absorption spectrometry. Samples were digested in a mixed acid of HClO4∶HNO3(V∶V=1∶4) under low temperature. The results showed that all samples are rich in Ca and Mg，while the conteats of Fe in Fu tea, Cu in Laoshan green tea, Zn in Anxi Tieguanyin tea and Laoshan green tea are the highest. The linear correlation coefficients were ＞0.9948, the spiked recovery ratio, 94.38%~105.00%, and the RSD was less than 2.26 %. This method is rapid and accurate. The experimental results of different kinds of tea are meaningful for customers.