Changes in the volatile components of virgin olive oil during fruit storage in aqueous media

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

“…There were also significant differences (p≤0.05) between the daytime and nocturnal oils for some of the compounds responsible for off-flavors: propyl acetate, pentanal and 2-penthylfuran ( Table 2). As it appears that olive storage at higher temperatures before oil processing promotes an increase in such undesirable compounds (Koprivnjak et al, 2000), this is to be avoided in the production of extra virgin olive oil. Also, good practice in olive handling recommends that the olives are processed as soon as possible after harvesting, and to avoid prolonged storage periods (Di Giovacchino et al, 2002;Kalua et al, 2007).…”

“…This is also promoted by high temperatures, prolonged storage periods, and lack of ventilation, which can all result in undesirable fermentation and affect the enzyme activities. This, in turn, encourages an increase in the volatile compounds that are responsible for off-flavors Koprivnjak et al, 2000Koprivnjak et al, , 2002.…”

“…Storage of the fruit can decrease the aldehyde and ester contents that are responsible for the positive aroma. At the same time, incorrect storage of both the fruit and the oil can produce the volatile compounds that are responsible for off-flavors Koprivnjak et al, 2000). There can thus be an absence in the C-6 aldehydes, alcohols and esters that are produced by the lipoxygenase pathway, with increased levels of many aldehydes from chemical oxidation, including hexanal from both chemical and enzymatic reactions, and the consequent characteristic off-flavors of olive oil.…”

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

“…C6 alcohols such as E-2-hexen-1-ol responsible for the sensory descriptor associated with the "ripe fruity, soft" and "green" aromatic sensory notes (Luna, Morales & Aparicio, 2006;Bendini et al, 2007), it ranged from 0.26% up to 1.03%, respectively in Kenine and Achajara almoubaraka OO samples. C5 alcohols such as 1-penten-3-ol and 2-methyl-1-butanol, compounds that are linked to "mouldy" and "rancid" defects (Koprivnjak et al, 2000), were found only in Achajara almoubaraka OO at a low amount (0.54%; 0.85% Respectively). The chemical composition of all the OO headspace was characterized by the presence of 12 volatile compounds in most of the all analyzed samples; however, their proportions were substantially different (Table 3), as follows: E-2-hexenal; ethanol; 3-methyl-1-butanol; Z-3-hexen-1-ol; 1-hexanol, methyl acetate; ethyl acetate; 3-pentanone; Z-3,7-dimethyl-1,3,6-octatriene; 5-E-3-ethyl-1,5-octadiene; E-4,8-dimethyl-1,3,7 nonatriene; Methyl-cyclodecane.…”

“…Levels can be modified by the conditions of crushing and malaxation used and depend on the level and the activity of enzymes involved in the various pathways (Angerosa, 2002;Angerosa, Basti, & Vito, 1999). Yet, other factors that influence the evolution of volatile compounds, responsible for aromas, are fruit maturity, irrigation, extraction methods, storage and condition of the fruit at harvest, cultivar and geographic region Ben Temime Campeol, Cioni, Daoud, & Zarrouk, 2006;Diego, Gonzalez, & Aparicio, 2010; Garcia-Gonzalez, Aparicio-Ruiz, & Aparicio, 2009;Gomez-Rico, Salvador, La Greca, & Fregapane, 2006;Haddada et al, 2007;Inarejos-Garcia, Gómez-Rico, Salvador, & Fregapane, 2010a;Koprivnjak, Procida, & Zelinotti, 2000;Venkateshwarlu, Meyer, & Jacobsen, 2004). The levels of major volatile components decreased in the course of ripening but were higher in irrigated olive trees (Gomez-Rico et al, 2006).…”