Impact of Selected Chemical Characteristics of Cold-Pressed Oils on their Oxidative Stability Determined Using the Rancimat and Pressure Differential Scanning Calorimetry Method

Abstract

In this study, 27 market and edible cold-pressed oils from 10 different oilseeds were analysed. Oxidative stability and the chemical composition of oils were evaluated. The oils were investigated for their primary quality, fatty acid composition, total phenolic content and antioxidant activity. Rancimat and pressure differential scanning calorimetry (PDSC) were used to assess oils oxidative stability. Principal component analysis (PCA) was conducted to determinate impact of selected chemical characteristics on tested oils’ oxidative stability in accelerated modes. PCA indicated that none of the chemical compounds correlated strongly with the oils’ oxidative stability determined by the Rancimat method. Correlation coefficients describing the impact of different chemical compounds on induction time determined using the Rancimat method were between r = −0.54 (C18:3) to r = 0.62 (chlorophyll pigments). Oxidative stability of oils determined using the Rancimat and pressure differential scanning calorimetry (PDSC) were characterised by low correlation (r = 0.66). According to the statistical analyses, oils were divided into four groups, which depend on the method of oxidative stability evaluation did not differ.