Effects of Geographical Origin and Tree Age on the Stable Isotopes and Multi-Elements of Pu-erh Tea

• Published in: Foods 2024-02, Vol.13 (3), p.473
• Main Authors: Chen, Ming-Ming, Liao, Qiu-Hong, Qian, Li-Li, Zou, Hai-Dan, Li, Yan-Long, Song, Yan, Xia, Yu, Liu, Yi, Liu, Hong-Yan, Liu, Ze-Long
• Format: Article
• Language: English
• Subjects: Accuracy; Age; Aging; Carbon; Carbon 13; Chemical properties; Chromatography; Copper; Discriminant analysis; Distribution; Erbium; Food research; Gadolinium; Gases; Geographical distribution; geographical origin; Isotopes; Lanthanum; Leaves; Magnesium; Manganese; mineral elements; Nitrogen; Parameters; Physiological aspects; Principal components analysis; pu-erh tea; Ratios; Reference materials; stable isotope; Stable isotopes; Tea; Tea (Plant); Terbium; tree ages; Trees; Variance analysis; Ytterbium; Yttrium
• ISSN: 2304-8158; 2304-8158
• DOI: 10.3390/foods13030473

Pu-erh tea is a famous tea worldwide, and identification of the geographical origin of Pu-erh tea can not only protect manufacture's interests, but also boost consumers' confidence. However, tree age may also influence the fingerprints of Pu-erh tea. In order to study the effects of the geographical origin and tree age on the interactions of stable isotopes and multi-elements of Pu-erh tea, 53 Pu-erh tea leaves with three different age stages from three different areas in Yunnan were collected in 2023. The δ C, δ N values and 25 elements were determined and analyzed. The results showed that δ C, δ N, Mg, Mn, Fe, Cu, Zn, Rb, Sr, Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu had significant differences among different geographical origins ( < 0.05). Mn content was significantly influenced by region and tree age interaction. Based on multi-way analysis of variance, principal component analysis and step-wised discriminant analysis, 24 parameters were found to be closely related to the geographical origin rather than tree age, and the geographical origin of Pu-erh tea can be 100.0% discriminated in cross-validation with six parameters (δ C, δ N, Mn, Mg, La, and Tb). The study could provide references for the establishment of a database for the traceability of Pu-erh tea, and even the identification of tea sample regions with different tree ages.