Oxidative Stability of Iranian Commercial Olive Oils

In the present study, the oxidative stability of nine Iranian commercial olive oils, including four virgin samples and five deodorized ones, was compared to that of two foreign virgin olive oils. In total, the foreign samples had the MUFA/PUFA ratios (av. 9.27) higher than those of domestic ones (av. 5.70). The peroxide and acid values of the olive oils studied ranged from 8.5 to 14.5 meq/kg and from 0.1 to 4.27 mg/g, respectively. Tocopherols content of the foreign olive oils (av. 436.7 ppm) was averagely higher than that of the domestic olive oils and even about two times that of domestic virgin ones (223.4 ppm). On average, the foreign virgin olive oils contained phenolic compounds (154.0 ppm) higher than that of the domestic ones (112.3 ppm) and especially deodorized olive oils (46.0 ppm). The oxidative stability of oil samples was suitably interpreted in terms of chemical composition data, so that the foreign virgin olive oils had more appropriate chemical composition in total, and therefore, indicated oxidative stabilities higher than those of the domestic virgin and deodorized olive oils.