The Effect of Heating on the Quality, Oxidative Stability and Fatty Acid Composition of Çekişte Olive Oil

Abstract

The aim of the study was to investigate the changes in main quality parameters, oxidative stability and fatty acid composition of olive oil obtained from Çekişte cultivar during heating. For this purpose, the olive oil, obtained from Aydın province in 2017 from Çekişte cultivar, was heated at 100°C under 20 L/h flow rate for totally 50 hours. The olive oil samples were heated for 10-hour intervals and analysed for their free fatty acid content, peroxide value, diene and triene (K232 ve K270) values, total phenol content, antioxidant activity, chlorophyll and carotenoid contents as well as fatty acid composition. Additionally, the oxidative stability of samples was determined which was expressed as induction time. Results showed that the main quality parameters of olive oil including free fatty acid content, peroxide value, diene and triene (K232 ve K270) values increased during heating. However, the content of total phenols, antioxidant activity, chlorophyll and carotenoid contents decreased gradually when heating time was prolonged. In a similar manner, the induction period decreased upon heating. The content of linolenic acid increased significantly at the end of heating process.