Odorants of Virgin Olive Oils with Different Flavor Profiles

Abstract

The potent odorants of virgin olive oils from Italy (I), Spain (S), and Morocco (M) were screened by aroma extract dilution analyses and gas chromatography olfactometry of headspace samples. After quantification, odor activity values (OAVs) were calculated by dividing the concentrations of the odorants in the oil samples by their nasally and retronasally determined odor threshold values in sunflower oil. On the basis of the nasal thresholds, the following compounds showed high OAVs in the oils given in parentheses: acetaldehyde (I, S, M), acetic acid (I, S), propanal (I), 1-penten-3-one (I), (E,Z)-2,4-decadienal (I, M), trans-4,5-epoxy-(E)-2-decenal (I, S, M), (Z)-3-hexenal (I, M), (E)-2-hexenal (I), (Z)-3-hexenyl acetate (I), 4-methoxy-2-methyl-2-butanethiol (S), ethyl 2- and 3-methylbutyrate (S, M), 2- and 3-methylbutanal (S), ethyl cyclohexylcarboxylate (M), and ethyl isobutyrate (M). Higher OAVs were additionally found for hexanal (I) and (Z)-2-nonenal (I, M) when retronasal odor thresholds were used as the basis. The potent odorants were dissolved in a refined plant oil in the concentrations found in the three olive oil samples. The flavor profiles of the models obtained were very close to those of the real samples, indicating that the different notes in the flavor profiles of these oils could be reproduced, e.g., green, fruity, black currantlike. Models missing one or several compounds with the same odor quality gave an insight into the importance of the odorants contributing to the flavor profiles of the oil samples. Keywords: Aroma extract dilution analysis; flavor analysis; flavor differences; flavor imitation; flavor profile analysis; isotope dilution asssay; sensory study; virgin olive oil