PHYSICOCHEMICAL PROPERTIES EVALUATION OF SOME COLD PRESSED NUT OILS FROM TURKEY WITH PRINCIPAL COMPONENT ANALYSIS

Nuts and their oils have been popular food ingredients for centuries and the nutritional supplements market is focusing on nuts oils due to their many health benefits. In this study peanut (Arachis hypogaea L.). hazelnut (Coryhis maxima Mill.), walnut (Juglans regia), almond (Prunus amygdalus) and pistachio (Pistacia vera) samples from Turkey have been used. Samples oils were extracted with the cold pressed method and evaluated in terms of fatty acid methyl esters (FAME) compositions, peroxide value (PV), free fatty acid (FFA), and the refraction index (RI) at 400 C. The analysis results arc evaluated by principal component analysis (PCA). According to PCA results, the oil samples from nuts have different characteristics and are seperated from each other with their FAME, FFA, PV and RI values. While hazelnut, pistachio and almond oils are showing similar characteristics, peanut and walnut oils are separated individually. Remarkable for walnut walnut was separation by means of polyunsaturated fatty acids. The results show that each nut has unique properties and the nut from Turkey can be considered as a raw material for food, nutritional supplements and natural cosmetics applications. FAME, FFA, PV and RI parameters can be preferred in order to assure the quality characteristics and purity of the nut oils while determining the possible adulterations.