Such observation was previously verified by Malheiro et al. (2012) when virgin olive oil was submitted to microwave heating. Being unstable primary oxidation products, the hydroperoxides are usually converted to secondary oxidation products (Laguerre et al. 2007). The control sample SFO had the higher level of PV compared to PLE treated samples (SFP1, SFP2 and SFP4) at all corresponding heating time, indicating a higher extent of primary oxidation in SFO. A slow raise in PV of the treated samples as compared with that of the control clearly showed the antioxidant capacity of the PLE. Based on the PV, the order of stability of oil samples was as follow: SFB> SFP4> SFP2> SFP1>SFO indicating that PLE was able to retard peroxide formation reaction. The para-anisidine values (p-AV) generally reflect the amount of aldehydic secondary oxidation products in oils (Al-Kahtani 1991). The p-AV in all the oil samples increased significantly (p