离子交换色谱法同时分析绿茶中有机酸和无机阴离子的含量

Simultaneous analysis with ion-exchange chromatography for the contents of organic acids and inorganic anions in green tea

目的 建立能够同时检测绿茶中有机酸和无机阴离子的方法 ,了解不同绿茶中有机酸和无机阴离子的含量。方法 将市售信阳毛尖茶、龙井茶和湖南茉莉花茶分别浸泡于新沸后蒸馏水中 2 0min ,过滤 ,过Shim - packIC阴离子交换柱 ,0 .75mmol·L-1邻苯二甲酸氢钾0 .2 5mmol·L-1邻苯二甲酸混合液洗脱 ,离子色谱仪分析。结果 经过简单的样品处理即可方便的同时检测茶叶中的多种有机酸和无机阴离子含量 ,各色谱峰分离良好。信阳毛尖茶、龙井茶和湖南茉莉花茶 3种绿茶中乙酸含量为 5 .71～ 6 .99mg·g-1,抗坏血酸 9.2 1～ 10 .87mg·g-1,苹果酸 3.6 6～ 5 .18mg·g-1,柠檬酸 6 .94～ 8.94mg·g-1,酒石酸 0 .80～ 1.5 9mg·g-1,琥珀酸 4 9.4 9～ 6 6 .79mg·g-1,H2 PO-47.76～ 8.88mg·g-1,Cl-1.5 2～ 2 .0 0mg·g-1,SO2 -43.6 3～ 4 .73mg·g-1。结论 不同产地绿茶中有机酸和无机阴离子的含量有所不同 。

Objective To establish an approach for simultaneous tests on organic acid and inorganic acid in green tea in order to learn about the contents of the two acids. Method Xinyang Maojian, Longjing Tea and Hunan Jasmine tea were first immersed in distilled water for 20 min and then were filtered.The filtrates were put through Shim-pack IC anion-exchange column and the elution was done in the mixed liquids of KHPh(0.75?mmol·L -1 ) and H 2Ph (0.25?mmol·L -1 ). Finally analysis was done with ion-chromatograph. Results The simultaneously measurement for the contents of various organic acids and inorganic acids in teas could be conveniently done after simple sampling, and the separation of chromatographic peaks were clear. The contents of the organic acids and inorganic anions in Xinyang Maojian, Longjing and Hunan Jasmine were as follows:acetic acid 5.71～6.99?mg·g -1 ,ascorbic acid 9.21～10.87?mg·g -1 ,malic acid 3.66～5.18?mg·g -1 ,citric acid 6.94～8.94?mg·g -1 ,tartaric acid 0.80～1.59?mg·g -1 ,succinic acid 49.49～66.79?mg·g -1 ,H 2PO - 4 7.76～8.88?mg·g -1 ,C1 - 1.52～2.00?mg·g -1 and SO 2- 4 3.63～4.73?mg·g -1 . Conclusion Green teas from different places are different in the contents of organic acids and inorganic anions.