Authenticating Tibetan pork in China by tracing the species and geographical features based on stable isotopic and multi-elemental fingerprints

A potential tool for authenticating Tibetan pork based on species and geographical origins was investigated by isotopic and multi-elemental fingerprints to compare Tibetan pork and plain pork from various regions in China. In this study, carbon, nitrogen, hydrogen and oxygen isotope compositions and concentrations of 50 elements of a total of 93 pork samples (Tibetan pork from Tibet and Sichuan, Jilin pork from Jilin and DLY pork from Liaoning) were determined and subjected to multivariate analysis, including linear discriminant analysis (LDA), partial least squares discriminant analysis (PLS-DA) and correlation analysis. The trace elements Fe, Cu, Rb, Mo, Cs, Ir, Co, Sr, Sm and four stable isotopes were determined as potential markers for identifying Tibetan pork. The discriminant model revealed good discrimination among pork samples based on species and regions, and the high accuracies of K-fold cross-validation (95.74% and 97.84%) indicated the reliability and stability of classification models. This study has demonstrated the efficiency of isotopic and multi-elemental technology in identifying Chinese high-altitude indigenous pigs.