Volatile Compounds, Profiles of Virgin Olive Oils Produced In the Eastern Morocco: Oxidative Stability and Sensory Defects

Abstract

Studies on flavor profiles of virgin olive oil (VOO) are becoming more and more numerous. The VOO aromas are determined by a mixture of chemicals in olive oil, which influence its quality. Various studies around the world have shown that the volatile compounds in VOO depend on the climate, cultivation and process.The present work is a first approach to compare volatile profiles of VOO largely produced in eastern of Morocco after 6 months of storage at ambient temperature in darkness. Oxidative stability measured by Rancimat method at 101˚C was also determined. VOO volatile profiles were examined using the solid-phase micro extraction fibre method (SPME) in conjunction with gas chromatography/mass spectrometer (GC/ MS). 84 volatile compounds were identified; they belong to various chemical classes, such as aldehydes, alcohols, esters, ketones, carboxylic acids and hydrocarbons. The main volatile compounds present in olive oil samples were compounds with 6 carbon atoms (C6) such as Hexanal, (E)-hex-2-enal, Z-3-Hexen-1-ol and 1-Hexanol. Ethanol and Z-3, 7-dimethyl-1, 3, 6-octatriene, methyl acetate and ethyl acetate were also found. In general, these compounds have been identified in all VOO analyzed samples. The chemical compositions of the analyzed virgin olive oil headspaces evidenced that the most representative compounds In Isly and Kenine were carboxylic acids accounted for 59.24%-49.7% respectively, whereas the volatile fraction of the oil from Achajara almoubaraka showed significantly higher amounts of the alcohols (46%). Concerning oxidative stability, Isly and Kenine OO, have lower stability values compared to Achajara almoubaraka. Their potential oxidative susceptibility is therefore much higher than Achajara almoubaraka.

Flavor profiles of monovarietal virgin olive oils produced in the Oriental region of Morocco

“…The attribution of a sensory note to this compound in the definition of VOO flavor is not clear. In fact, few studies reported the presence of these compounds in VOO without taking their sensory role into consideration (Vichi et al, 2003;Tanouti et al, 2012). Overall, the volatile compounds with higher levels in Koroneiki VOO have mainly a positive correlation with factor 1.…”

Effects of Olive Trees Age on the Minor Components of Oueslati Virgin Olive Oils Produced from Olives Harvested at Different Ripening Degrees

“…3-Ethyl-1,5-octadiene (I) was detected Table 3 Volatiles composition (mg 4-methyl-2-pentanone kg −1 oil) expressed as mean values and standard deviations of Oueslati olive oil from young and adult trees at different stages of maturation only at the green maturation stage of olive oils from young trees: the presence of this hydrocarbon could play an important role in the typical flavors of this oil. However, (Z)-2-penten-1-ol, which is among the compounds responsible for the green odor notes of VOO aroma [32], increased significantly during maturation in oil samples from both young and adult trees. Compared to VOO from adult olive trees, VOO from young olive trees were characterized by higher amounts of (Z)-2-penten-1-ol.…”

First comprehensive characterization of volatile profile of north Moroccan olive oils: A geographic discriminant approach

“…To the best of our knowledge, this is the first detailed and comprehensive characterization study of volatile compounds (evaluating their use for the geographical classification too) of Moroccan VOOs. Only a recent work characterizing the effect of storage on volatile compounds of eastern Moroccan olive oils (Tanouti, Serghini-Caid, Sindic, Wathelet, & Elamrani, 2012) can be found in the scientific literature.…”