Physicochemical Properties and Oxidative Stability of Some Virgin and Processed Olive Oils

This study investigated the fatty acids profile, oxidative stability indices, and bioactive compounds of virgin and processed olive oils (Leccino and Frantoio cultivars). Results showed that fatty acid profile of the studied oils contained mostly oleic acid followed by palmitic and linoleic acid. Acid values of virgin Frantoio and processed Leccino were ۰.۷۸ and ۰.۱۸ mg KOH/g oil, with peroxide values (PV) of ۸.۷۴ and ۶.۰۳ meq O۲/kg oil, respectively. Virgin Leccino had the highest oxidative stability index with induction period of ۱۸.۸۳ h. The highest contents of phenolics, ۳۲۱.۱۴ mg/kg, tocopherols, ۴۵۵.۲۵ mg/kg, and sterols, ۲۱۸۹.۱ mg/kg, were recorded in virgin Leccino oil. Laboratory processing of virgin olive oil decreased the phenolics to ۷۰%, tocopherols to ۵۰%, and sterols to ۲۵%. Finally, based on the higher content of antioxidant compounds, the virgin Leccino oil had higher oxidative stability and bioactivity than Frantoio oil.

Keywords:

Bleaching , Deodorization , Rancimat test , phenolic compounds