Comparative study of extra virgin olive oil flavor profile of Koroneiki variety (Olea europaea var. Microcarpa alba) cultivated in Greece and Tunisia during one period of harvesting

The effects of geographical region, irrigation and ripening degree of olives on the profile of volatile compounds isolated by monovarietal virgin olive oils from Crete and Tunisia of Koroneiki variety (Olea europaea var. Microcarpa alba) using the SPME GC/MS technique were investigated. Fruits obtained from Greece (island of Crete) and Tunisia (Sfax region) were picked at three and two different growth stages respectively and then immediately processed. The most important compounds identified were esters, alcohols, carbonyl compounds and hydrocarbons. The main volatile compounds present in the oil samples were C6 derivatives, such as E]-2-hexenal, E]-2-hex-1-enol, Z]-3-hexen-1-ol and 1-hexanol. In addition to C6 compounds, the aroma of the studied samples contained reasonable amounts of various classes of C5 components. The tested oil samples showed different volatile profiles. Specifically, the concentration of total esters, carbonyl, C6 and C5 compounds increased significantly with the ripening degree in Cretan, but not in Tunisian olive oils. Principal component analysis of the results indicated that primary maturity and geographical region rather than irrigation affected significantly the volatile’s profile of olive oil.