Relationship between volatile compounds and sensory attributes of olive oils by the sensory wheel

Abstract

Sixty‐five volatile compounds and 103 sensory attributes were evaluated in 32 virgin olive oil samples from three different Mediterranean countries. Volatile compounds were analyzed with a dynamic headspace gas‐chromatographic technique by using a thermal desorption cold‐trap injector. The sensory analysis was conducted by six panels composed of assessors from the United Kingdom, Spain, the Netherlands, Greece and Italy. Principal‐components analysis of sensory attributes was used to construct a statistical sensory wheel that represents the whole virgin olive oil flavor matrix. This wheel is composed of seven sectors that show the basic perceptions produced by the oil: green, bitter‐pungent, undesirable, ripe olives, ripe fruit, fruity and sweet. The boundaries of each sector were calculated from the circular standard deviation of its sensory attributes. The relationship between sensory and instrumental analysis was determined by projecting volatiles onto the sensory wheel. Correlations of each volatile with the first two components of the principal‐components analysis were taken as its coordinates (x, y) in the sensory wheel. Volatiles took up the most appropriate place within the sector that corresponded with their perception, and often close to the sensory attributes that explained their sensory properties. A gas‐chromatographic/sniffing method was applied to virgin olive oil samples to assess the aroma notes that corresponded to olive oil volatile compounds and to verify the relationships found by the sensory wheel procedure. Most (89%) of the volatiles were well classified. Use of the statistical sensory wheel as an appropriate method to relate volatile and sensory data was clearly demonstrated.

Influence of the nocturnal harvesting of olives from Salento (Italy) on the quality of the extra virgin olive oil

“…** (Aparicio et al, 1994, 1996and Aparicio and Luna 2002Blekas et al, 1993;Di Giacinto et al, 2010;Morales et al, 1995;Reiners and Grosch 1998).…”

Olive Oil Composition: Volatile Compounds

“…Among these compounds, only a small fraction contributes to the aroma of olive oil . The most common olive oil volatiles have 5 to 20 carbon atoms and include short-chain alcohols, aldehydes, esters, ketones, phenols, lactones, terpenoids and some furan derivatives (Reiners & Grosh, 1998;Delarue & Giampaoli, 2000;Kiritsakis, 1992;Boskou, 2006;Vichi et al, 2003aVichi et al, , 2003bVichi et al, , 2003cAparicio et al, 1996;Morales et al, 1994;Flath et al, 1973;Morales et al, 1995;Bortolomeazzi et al, 2001;Bentivenga et al, 2002;Bocci et al, 1992;Servili et al, 1995;Fedeli et al, 1973;Fedeli, 1977;Jiménez et al, 1978;Kao et al, 1998;Guth & Grosch, 1991). As all vegetable oils, olive oil comprises a saponifiable and a non-saponifiable fraction and both contribute for the aroma impact.…”

« Nez et langues électroniques » : bilan et perspectives pour les huiles alimentaires

“…D'autres méthodes d'extraction sont utilisées pour les analyses instrumentales séparatives, et pourraient être utilisées pour les huiles. Une description exhaustive de chaque technique peut être trouvée dans la référence [6] : Le headspace dynamique (D-HS) est utilisé de manière classique sur des tubes adsorbants Tenax ® , avec d'excellents résultats pour l'identification des marqueurs de qualité ou de défauts [7]. Le principal avantage est l'épuisement (extraction complète) des composés depuis la matrice, sans être tributaire des coefficients de partage.…”