Origin Characteristics and Traceability Discrimination of Jiangxi Tea based on Rare Earth Element Contents

To investigate the rare earth elements residues in teas from Jiangxi Province in order to provide suggestions on reducing rare earth elements (REEs) contamination, and to improve the quality of tea. A method for geographical origin discrimination of tea from Jiangxi Province was established to provide technical support for the protection of geographical indication products and for tracing the geographic origin of agricultural products. One hundred and thirty-eight samples of tea were collected from three producing areas: The counties of Suichuan, Lushan and Wuyuan in this study. Inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) was used to determine the contents of 15 rare earth elements in tea. Principal component analysis (PCA) and fisher linear discriminant analysis (FLD) were applied to differentiate the tea geographical origin. The results showed that the total amount of rare earth oxides in the teas were 0.44~1.57 mg·kg⁻¹ and did not exceed the national limit standard of rare earth elements in tea (GB 2762-2012). After principal component analysis, three principal components were extracted from 15 rare earth elements (REEs), representing 90.66% of the total index information. Fisher discriminant analysis showed that the correct discriminant rates of back generation test and cross test were 100% and 99.3%. It is proved that rare earth elements (REEs) tracing technology can be used in tea origin discrimination and provide the identification basis for the protection of the origin of Jiangxi famous tea brands in the future.