Characterization and Discrimination of Virgin Olive Oils from Different Moroccan Geographical Areas Using MIR Spectroscopy Coupled to Chemometric Methods

A methodology based on Mid-infrared (MIR) spectroscopy, combined with multivariate analysis methods, was applied in order to Discriminate and characterize virgin olive oils from four Moroccan geographical areas.49 Samples of virgin olive oil were collected in November 2013 from mills in the Tadla-Azilal Moroccan region then stored at 4C. The characterization of the olive oils was made determining several variables the free acidity, the peroxide value, spectrophotometric index, carotenoids, and chlorophylls. The same samples were also analyzed busing Infrared spectroscopy. Classification methods (PCA and PLS-DA) were applied on the spectral data to classify olive oils according to their geographical areas. The results were quite satisfactory, in spite of the similarity of cultivar compositions between four different origins. The spectroscopic methods, combined to chemometric strategies, could represent a reliable, cheap and fast classification tool.