Establishment and Similarity Evaluation of Fingerprint of Different Varieties of Tea

Objective:The fingerprints of different varieties of tea were established by HPLC to provide a reference for the quality control and scientific application of tea. Methods:A total of 33 batches of 10 varieties of tea samples were used as experimental materials. 75% methanol water was used for twice reflux extraction. The chromatographic conditions were as follows:Gradient elution was 0.2% phosphoric acid aqueous solution as mobile phase A and acetonitrile was as mobile phase B,column temperature was 30 ℃,flow rate was 1.0 mL/min,and detection wavelength was 280 nm. The fingerprint similarity software was used for data analysis to establish a common fingerprint pattern of fingerprint of different varieties of tea. Results:The similarities of 10 varieties of tea ranged from 0.681 to 0.999 with five common peaks,among which three common peaks of gallic acid,epicatechin gallate,epigallocatechin gallate were identified. 33 batches of tea samples could be clustered into 3 groups by cluster analysis(Meitan Cuiya Tea,Fenggang Zinc Selenium Tea,Duyun Maojian Tea,Biluochun Tea,West Lake Longjing Tea,Tianzhu Tea and Emerald Tea were clustered in one category,Dahongpao Tea and Tieguanyin Tea were clustered in one category,Zunyi Black Tea was clustered in one category). Conclusion:There were significant differences in the quality of different varieties of tea,but the quality of the same variety,different grades and different manufacturers had little difference. The method is simple,accurate and reproducible,and it can distinguish tea with different manufacturing techniques to provide reference for tea quality control and scientific application.