Flavor components of olive oil—A review

Abstract

The unique and delicate flavor of olive oil is attributed to a number of volatile components. Aldehydes, alcohols, esters, hydrocarbons, ketones, furans, and other compounds have been quantitated and identified by gas chromatography-mass spectrometry in good-quality olive oil. The presence of flavor compounds in olive oil is closely related to its sensory quality. Hexanal, trans-2-hexenal, 1-hexanol, and 3-methylbutan-1-ol are the major volatile compounds of olive oil. Volatile flavor compounds are formed in the olive fruit through an enzymatic process. Olive cultivar, origin, maturity stage of fruit, storage conditions of fruit, and olive fruit processing influence the flavor components of olive oil and therefore its taste and aroma. The components octanal, nonanal, and 2-hexenal, as well as the volatile alcohols propanol, amyl alcohols, 2-hexenol, 2-hexanol, and heptanol, characterize the olive cultivar. There are some slight changes in the flavor components in olive oil obtained from the same oil cultivar grown in different areas. The highest concentration of volatile components appears at the optimal maturity stage of fruit. During storage of olive fruit, volatile flavor components, such as aldehydes and esters, decrease. Phenolic compounds also have a significant effect on olive oil flavor. There is a good correlation between aroma and flavor of olive oil and its polyphenol content. Hydroxytyrosol, tyrosol, caffeic acid, coumaric acid, and p-hydroxybenzoic acid influence mostly the sensory characteristics of olive oil. Hydroxytyrosol is present in good-quality olive oil, while tyrosol and some phenolic acids are found in olive oil of poor quality. Various off-flavor compounds are formed by oxidation, which may be initiated in the olive fruit. Pentanal, hexanal, octanal, and nonanal are the major compounds formed in oxidized olive oil, but 2-pentenal and 2-heptenal are mainly responsible for the off-flavor. JAOCS 75, 673-681 (1998).

An innovative method to produce green table olives based on “pied de cuve” technology

“…presence of those compounds suggests their enzymatic origin by lipoxygenase activity on polyunsaturated fatty acids of drupes. A similar pathway has been identified in the biosynthesis of volatile compounds of olive oil (Kiritsakis, 1998;Angerosa et al, 2000;Salas et al, 2000;Williams and Harwood, 2000;Ridolfi et al, 2002;Salas, 2004;) as well as in the brine of fermented table olives by LAB and yeasts (Sabatini et al, 2008). 2-phenylethanol could be produced in yeasts by L-phenylalanine catabolism (Sabatini et al, 2009).…”

Phenolic Molecules in Virgin Olive Oils: a Survey of Their Sensory Properties, Health Effects, Antioxidant Activity and Analytical Methods. An Overview of the Last Decade Alessandra

“…The combined effect of the taste, odor (directly via the nose or indirectly through the retronasal path via the mouth) and chemical responses (pungency, astringency, metallic, cooling or burning) gives rise to the sensation generally perceived as "flavor" [126]. VOO, when extracted from fresh and healthy olive fruits (Olea europaea L.) and properly processed and stored, is characterized by an unique combination of aroma and taste that is highly appreciated [127][128]. The sensory aspect, due to the use of VOO as a seasoning on cooked and especially raw foods, has great repercussions on its acceptability.…”

Heating on the volatile composition and sensory aspects of extra-virgin olive oil

“…A decrease in the alcohols, esters, and terpenes was observed with increased heating temperature, whereas an increase in oxidized compounds, such as aldehydes and carboxylic acids, was observed with increased heating temperature (Figure 1), suggesting more drastic deterioration of olive oil at higher temperatures. In fact, high rates of aldehyde formation (mainly nonanal), in addition to increased carboxylic acids, have been observed during the oxidation of olive oil (KIRITSAKIS, 1998). These compounds are reported to negatively influence the sensory characteristics of oils (VICHI et al, 2003;KALUA et al, 2007).…”

“…Hexanal and nonanal are widely used to assess lipid oxidation (KIRITSAKIS, 1998;KALUA et al, 2007). The volatile profiles are directly linked to the sensory perception of olive oil.…”