NMR and multivariate data analysis to assess traceability of argentine citrus

Argentine citrus industry stands out among the top ten largest producers of citrus of the world. Traceability is a key point of the quality control in the international trade context. Discrimination between orange juices produced from different geographical regions in Argentina (San Pedro and Entre Rios), has been achieved by applying principal components analysis (PCA) and partial least-squares - discriminant analysis (PLS-DA) to H-1 NMR spectra of the juices. Different regions of the spectra were analyzed in view of the large range of signal intensities and the chemometric treatment of the NMR data has successfully distinguished the juice of different origins/varieties, as well as the metabolites responsible for their separation. Examination of the PCA loadings showed that citric acid and ethanol levels were the main chemical variables for sample discrimination.