Classification of extra virgin olive oils according to their genetic variety using linear discriminant analysis of sterol profiles established by ultra-performance liquid chromatography with mass spectrometry detection

A method to classify extra virgin olive oils (EVOOs) according to their genetic variety using sterol profiles obtained by ultra-performance liquid chromatography (UPLC) with atmospheric pressure chemical ionization mass spectrometry (APCI-MS) detection has been developed. The optimal separation conditions were obtained using a gradient acetonitrile/water (0.01% acetic acid) at a flow rate of 0.8 mL min(-1) and 10 degrees C. Linear discriminant analysis (LDA) models were constructed with the 11 UPLC-APCI-MS sterol peaks taken from the selective ion recording mode chromatograms. Ratios of the peak areas selected by pairs were used as predictors. With the sequential application of two LDA models and using a 95% probability, the EVOO samples belonging to seven genetic varieties mainly produced at La Comunitat Valenciana, Spain, were correctly classified with a prediction capability higher than 97%. (C) 2010 Elsevier Ltd. All rights reserved.