Discrimination of extra virgin olive oils from five French cultivars: En route to a control chart approach

Abstract The control of varietal origin is an important issue to insure the authenticity of olive oils. In this study, extra virgin olive oils from five French cultivars were discriminated by applying partial least square discriminant analysis (PLS1-DA) to their fatty acid and squalene compositions obtained by gas chromatography. Two decision rules were compared to determine the varietal origin of predicted samples: either a classical PLS-DA approach with uncertainty zones, or a control chart approach with warning and control limits. The control chart approach, being focused on characteristic samples from each modelled cultivar, is able to deal with classes having unbalanced number of samples and to identify atypical samples.