Oxidation kinetics of soybean oil/anhydrous milk fat blends: A differential scanning calorimetry study

The oxidation kinetics of soybean oil (SBO)/anhydrous milk fat (AMF) blends was studied by differential scanning calorimetry (DSC). Lipid blends containing 0–100% of SBO in AMF at 10% intervals were analyzed. Samples were heated in the DSC at different heating rates (2.5, 5.0, 7.5, 10.0 and 12.5 °C/min) and oxidation kinetics parameters from the Arrhenius equation (activation energy, pre-exponential factor and oxidation rate constant) were calculated using the Ozawa–Flynn–Wall method. Results show a significant increase in the oxidation rate (k) with temperatures for 60–90% SBO blends. The increase in k with SBO addition was only significant for 240 and 250 °C. A significant correlation between the rate constant and the chemical composition of the samples was not observed. This behavior suggests possible interactions among fatty acids present in the blends.