Potential of LC-MS phenolic profiling combined with multivariate analysis as an approach for the determination of the geographical origin of north Moroccan virgin olive oils

Abstract

The applicability of two different platforms (LC-ESI-TOF MS and LC-ESI-IT MS) as powerful tools for the characterisation and subsequent quantification of the phenolic compounds present in north Moroccan virgin olive oils was assessed in this study. 156 olives samples of "Picholine Marocaine" cultivar grown in 7 Moroccan regions were collected and olive oils extracted. The phenolic profiles of these olive oils were studied using a resolutive chromatographic method coupled to ESI-TOF MS (for initial characterisation purposes) and coupled to ESI-IT MS (for further identification and quantification). 25 phenolic compounds belonging to different chemical families were identified and quantified. Secoiridoids were the most abundant phenols in all the samples, followed by phenolic alcohols, lignans and flavonoids, respectively. For testing the ability of phenolic profiles for tracing the geographical origin of the investigated oils, multivariate analysis tools were used, getting a good rate of correct classification and prediction by using a cross validation procedure.

Keywords: Geographical origin; Liquid chromatography–mass spectrometry; Multivariate analysis; Phenolic compounds; Virgin olive oil.