Effect of Cultivar and Geographical Origin on the Volatile Composition of Greek Monovarietal Extra Virgin Olive Oils

Abstract

Extra virgin olive oil (EVOO) is highly appreciated by consumers for its unique sensory characteristics that are directly related to its volatile composition. The objective of this study was to investigate the effect of cultivar and geographical origin on the volatile composition of Greek monovarietal EVOOs. Samples of three local cultivars (Koroneiki, Kolovi and Adramytini) originating from three areas of Greece (Crete, Lesvos and the Peloponnese), spanning two consecutive harvesting periods, were selected. Their volatile components were determined using headspace solid-phase microextraction combined with gas chromatography–mass spectrometry. More than 70 volatile compounds were identified. Alcohols were the dominant class (43–50%), followed by ketones (12–24%), esters (12–18%) and aldehydes (4–12%). The most prominent volatile compounds were (Z)-3-hexen-1-ol (6–11%), 1-penten-3-ol (7–11%), (E)-3-hexenyl acetate (0.5–11%) and 3-pentanone (8–16%). Significant differences were observed and highlighted. Clear separations between samples from different cultivars and geographic provenances were achieved using multivariate analysis and the most discriminating volatiles were identified. Additionally, using multivariate receiver operating characteristic (ROC) curve analysis, a combination of five chemical markers was found superior (area under the curve, AUC: 1.00; predictive accuracy: 100%) for the correct classification of Koroneiki EVOOs according to geographical origin.