Evaluation of the Volatile Fraction of Commercial Virgin Olive Oils From Tunisia and Italy: Relation With Olfactory Attributes

Abstract

The volatile profile of fourteen commercial virgin olive oils (VOOs) produced by Tunisian and Italian olive cultivars from different geographical areas and collected from local markets and farms was evaluated by means of headspace‐solid phase microextraction and gas chromatography‐mass spectrometry analysis. All the samples were also analyzed by a group of fully trained assessors to define their olfactory attributes. The concentrations of volatile compounds as well as the nuances exhibited large variability among different kind of samples confirming that the typicality of VOOs in terms of both organoleptic and compositional characteristics greatly depends on both olive variety and quality. In particular, VOOs from Chetoui were found to exhibit both volatile profiles and sensory notes very similar to Italian samples. Data relative to the main volatile compounds were related to both positive and negative olfactory notes and sensory defects found in some oil samples were well confirmed by volatile marker presence. PRACTICAL APPLICATIONS Virgin olive oil flavor is strongly connected with the qualitative–quantitative composition of volatile compounds, which determine the whole of olfactory perceptions. This study, carried out on several commercial virgin olive oil samples from different cultivar and geographical origin of Tunisia and Italy revealed that the application of headspace‐solid phase microextraction to the analysis of volatile compounds and their identification and quantification by gas chromatography coupled with quadrupolar mass‐selective spectrometry can be of great interest not only for the comparison of flavor characteristics of oil samples but also for the evaluation of cultivar‐environment influence on virgin olive oil aroma if associated to sensory evaluation performed by an experts' panel.

Understanding Olive Oil Stability Using Filtration and High Hydrostatic Pressure

“…The volatile organic compound content of the oil samples was studied as the three following groups of compounds, in relation to their assumed role in oil sensory quality: (i) compounds with five and six carbon atoms, which are usually associated with the lipoxygenase (LOX) pathway and, consequently, with the "fruity" and "green" positive sensory attributes [25]; (ii) microbial metabolite compounds, which are usually associated with negative sensory attributes such as "fusty", "muddy", "vinegary" and "mouldy" defects [2,15,17]; (iii) compounds with seven, eight and nine carbon atoms, which are usually associated with the "rancid" negative sensory attribute [2,3]. The list of the above measured compounds is presented as Supplementary Material in Table S2.…”

“…EVOO must also have both a minimum positive "fruity" attribute and no negative sensory attributes (i.e., defects). Panel testing is the official method to measure the above attributes, even though some relationships have been reported in the literature between sensory perception and volatile organic compound content [2,3].…”

Aroma compounds and sensory characteristics as biomarkers of quality of differently processed Tunisian virgin olive oils

“…Aldehydes, alcohols, esters, hydrocarbons, ketones and other derivatives have been identified by gas chromatography and mass spectrometry (Flamini, ; Issaoui et al ., ). Many of them contribute to the distinctive sensorial characteristics that make extra virgin olive oil so typical (Kotti et al ., ). In the present study, a matrix of correlation was established between aromatic compounds and sensorial notes.…”

Flavor of Wine

“…Stepwise LDA was applied to the 17 selected volatiles in order to discriminate the samples on the basis of their origin, and 91% of correct classifications were obtained by only three volatiles: (3E)-hexa-1,3-dien-5-yne, 2-methylpropan-1-ol, and [(Z)-hex-3-enyl] acetate. Kotti et al (2011) analyzed olive oils that originated from Italy and Tunisia using HS-SPME-GC-MS followed by PCA. Although some differences between Italian and Tunisian samples were evidenced, it was not possible to obtain a clear discrimination of samples of different geographical origins on the bases of volatile compounds.…”