Optimization of Oil Oxidation by Response Surface Methodology and the Application of this Model to Evaluate Antioxidants

The oxidative stability of oils is a complex process influenced by several factors, making the evaluation of antioxidant effects of new compounds difficult. Thus, the objective of this study was to apply a factorial design to obtain the combination of factors that maximizes the formation of oil oxidation products, and use this model to evaluate the antioxidant activity of different compounds. Temperature, Fe²⁺ and ascorbyl palmitate were evaluated in two full-factorial designs (2³ and 3²). The validated optimized oxidation model was obtained by adding 1.47 mmol/L of Fe²⁺ and 1.54 mmol/L of ascorbyl palmitate to flaxseed oil stripped of tocopherol kept at 40 °C for 8 days. Antioxidant activities of six compounds were evaluated using this model. All antioxidant samples were statistically different (p < 0.001) at 200 ppm concentration, indicating the efficiency of the optimized model to evaluate the antioxidant action of natural and synthetic compounds.