Relationship Between Sensory Evaluation Performed by Italian and Spanish Official Panels and Volatile and Phenolic Profiles of Virgin Olive Oils

Virgin olive oil (VOO) is typified by characteristic, pleasant sensory notes that differentiate it from other edible oils. Sensory taste, together with nutritional aspects, is the main reason for the increase in consumption of VOO in recent years. Sensory analysis is required by European Official Regulations for olive oil in order to classify the product in commercial categories. In this study, the relationship between sensory and chemical composition has been investigated. In particular, 16 VOO samples (15 from a single variety of olives), produced in Italy and Spain (eight from each country), were analyzed. Sensory attributes were valued by four panels (three officially recognized both by IOOC and National Ministry: two Italian and two Spanish) employing a total of 59 tasters. Volatile and phenolic compounds were related to olfactory and gustative notes, respectively. Volatile compounds were then separated, identified, and quantified, starting from oil samples, by solid phase microextraction and capillary gas chromatographic analysis using a mass spectrometry detector (SPME/cGC-MSD). Furthermore, the phenolic profile was examined by high-performance liquid chromatography with diode-array and mass spectrometry detectors (HPLC-DAD/MSD). Correlations were found between the major volatile compounds (sum of aldehydes C6) and orthonasal perception of olive fruity and retronasal odor of almond. Additional correlations with bitterness and pungency were observed for tyrosol and oleuropein aglycon, respectively.