A Kinetic Approach to Evaluate the Structure‐Based Performance of Antioxidants During Lipid Oxidation

Thermal kinetic parameters of fish oil oxidation, as affected by o‐hydroxyl, o‐methoxy, and alkyl ester derivatives of p‐hydroxybenzoic acid in various concentrations (0.02% to 0.16%) at 35 to 55 °C, were calculated. The average extent of increase (2% to 10%) in the values of free energy of activation, ?G⁺⁺, as well as the average extent of change in the Arrhenius equation parameters, including activation energy (E_a, –40.5% to 13.6%) and frequency factor (A, –55.0% to 4.3%), could be employed well to show structure‐based performance of antioxidants. Temperature coefficient (T_C) and Q₁₀ number, which were considered as the quantitative measures of thermal sensitivity of the lipid system, showed changes from –40.3% and –27.2% to 13.5% and 11.5%, respectively, in the presence of the antioxidants.