• Electronic nose;
  • extra-virgin olive oil;
  • solid-phase microextraction–gas chromatography;
  • vitamin E;
  • volatile compounds


Changes in odour of Arauco (ARA) and Arbequina (ARB) extra-virgin olive oil (OO) were monitored during frying by electronic nose (EN) and solid-phase microextraction–gas chromatography methodologies. Degradation of α- and γ-tocopherols was monitored by HPLC. Electronic nose data and volatile compounds were analysed at intervals of 15 min (t15) during 60 min of frying (t60). α- and γ-tocopherols were determined at intervals of 5 min (t5) during 30 min of frying (t30). Principal components analysis applied to EN data showed one component, PC1 which accounted 96.6% of the total odour variation. SnO2 sensors had a positive correlation with PC1. ARA variety corresponding to frying t60 had the highest positive correlation with PC1. Analysis of variance results for volatile compounds showed an increase on production for: 3-methyl butanal, n-pentanal, n-hexanal, n-heptanal and n-nonanal at 15 min of frying for ARB OO and at 30 min for ARA OO. α-tocopherol and γ-tocopherol showed an important decrease after the first 5 min of frying for ARB OO and at 15 min for ARA OO.