CHARACTERIZATION OF ITALIAN EXTRA VIRGIN OLIVE OILS USING H-1-NMR SPECTROSCOPY

High-field (600-MHz) proton nuclear magnetic resonance (H-1-NMR) spect roscopy was applied to the analysis of 55 extra virgin olive oil sampl es from four Italian regions (Campania, Lazio, Sicily, and Umbria) and obtained from different olive varieties. The multivariate statistical analysis (PCA, hierarchical clustering) performed on the normalized i ntensities of H-1-NMR resonances due to minor components (beta-sitoste rol, n-alkenals, trans-2-alkenals, and other volatile compounds) allow s a good classification of oil samples obtained from traditional varie ties with respect to the region of origin (96% of oils correctly class ified). Samples obtained from one new experimental cultivar (FS-17) we re not correctly classified, indicating a strong contribution of olive variety on the chemical composition of virgin olive oils. The potenti al contribution and limits of NMR in the authentication of virgin oliv e oil geographical origin and variety are discussed.