A sensory and metabolomic approach for the "zonation" of typical extra virgin olive oils: an Italian case study

Metabolites found in the extra virgin olive oils can be tracers for some enzymatic activity. The presence and activity of enzymes is strictly related to genetic factors (as olive cultivar) and environmental conditions. The characterization of minor components of extra virgin olive oil, in particular volatile compounds and phenolic molecules, may contribute to the identification of the cultivar–environment interaction. Many of these compounds can be considered to be direct metabolites produced by intracellular biogenic pathways. In this work different analytical approaches were applied for the characterization of extra virgin olive oils produced from autochthon varieties of olives from Brisighella area which has been sampled specifically to carry on a study of zoning, by sampling oils obtained in the same product geographical district, but from different agronomic (types of soils) and agricultural practices (as irrigation). According to the Reg. UE 61/2011, basic quality parameters and additional determinations (free acidity, peroxide number and spectrophotometric indices) has been carried on to be able to discriminate the quality of the samples. The sensory evaluation of the products, conducted by a panel of fully trained judges, and the comparison of the volatile analyses by SPME/GC-MSD and E-Nose as well as the determination of phenolic compounds by HPLC-DAD/MSD were conducted together with the aim to highlight the peculiarities that constitute an important element of typicality valorization. In this way an in-depth study of the samples has been carried out in order to detect all the specific characteristics that could contribute to discriminate between samples to underline their typicality attributes. The research was carried out with the financial contribution of the TERRA DI BRISIGHELLA® - CAB.