Geographical Authentication of Peach in China Based on Stable Isotope Combined with Multielement Analysis of Peach Juice

Abstract The authenticity of the geographical origin of peach is crucial because of the increased awareness of consumers on the high quality and safety of foodstuff. This study was conducted to discriminate 150 peach samples from six regions in China by using stable isotope data coupled with multielement analysis. The ratios of three types of stable isotopes (δ13C, δ2H and δ18O) and the contents of 18 elements were employed to develop classification models that could trace the geographical origin of peach samples. Results of principal component analysis can distinguish the samples cultivated from coastal and inland regions, mainly attributed to H and O isotope ratios. Furthermore, stepwise linear discriminant analysis and orthogonal partial least square discriminant analysis provided a clear discrimination of the peach samples from different regions. The major important variables responsible for the differentiation in these models were δ2H, δ13C, Na, Cd, V, Al, δ18O, Be, K, Co, Cu and Ag. The findings also helped elucidate the variations in the isotope ratios of peach in terms of geographical origins. On the basis of stable isotope combined with multielement analysis, this study offered an effective tool of geographical classification for the control of fraudulent geographical labeling of peaches traded in fruit markets.