Investigation of oxidative stability and antioxidant properties of apricot kernel oil

In this study, with the aim of determination the effect of roasting on antioxidant properties and oxidative stability of apricot kernel oil, the kernels roasted for 5, 10, 15, 20 and 30 min at 180 °C and oils were obtained by solvent extraction. Oxidative stability were determined by the predictive methods; DSC, Rancimat and FT-IR methods and measurement based methods; Peroxide value, p-anisidine value determinations. Antioxidant activity tests were applied to both bulk oils and methanolic oil extracts. Tocopherol isomers and fatty acids were also determined.In this work, blood cholesterol and liver catalase, glutathione peroxidase and malondialdehyde levels of rats, fed with diet containing apricot kernel oil, were determined and compared with the animals fed with sunflower containing diet.Among apricot kernel oil samples, 15 and 20 min roasted samples showed the lowest and 5 min roasted sample showed the highest peroxide values. Similar results were obtained from p-anisidine tests. According to the results obtained from predictive oxidative stability tests, depending of the method, 15, 20 and 30 min roasted samples showed the longest induction periods.Antioxidant activities of samples increased by roasting, but increases in antioxidant activity of methanolic extract were more remarkable in comparison to bulk oils.Apricot kernel oil, caused increase in LDL and total cholesterol levels, whereas cause decrease in HDL and triglyceride levels. On the other hand, apricot kernel oil affected liver antioxidant parameters by elevating catalase and glutathione peroxidase and lowering malondialdehyde levels.Apricot kernel oil which were found to rich in oleic and linoleic acids, found to contain ?-tocopherol as a major tocopherol isomer. The amount of this compound was decreased by roasting degree.