Influence of chemical composition of olive oil on the development of volatile compounds during frying

Abstract

In this study, 15 virgin olive oils from an industrial oil plant in the Abruzzo region were analyzed in terms of the volatile compounds responsible for the characteristic odor and olfactory perception of virgin olive oils and its modification upon frying (up to 60 min of heat treatment). Dynamic headspace–gas chromatography–mass spectrometry analysis was used to evaluate the volatile profile before and after each frying step and examine correlations with qualitative characteristic of oil (fatty acid composition, total phenolic compound content, tocopherols and pigments). The chemometric approach (genetic algorithms–partial least squares/multiple linear regression) developed for this study is a novel model for data treatment to select important variables in olive oil composition and understand their influence on spoilage during frying. An inverse correlation between oleic acid content and formation of toxic volatiles such as acrolein and crotonal during frying was demonstrated. Moreover, it was also observed that pigments such as chlorophylls, pheophytins, and carotenoids may prevent the formation of some aldehydes during frying.