Kinetics-thermodynamics of the antioxidant activity of propolis extracts in pork pâté

This study aimed to evaluate the kinetic-thermodynamic mechanism of propolis extracts (PE) in controlling lipid oxidation in pork pâté. The pâtés were prepared and supplemented with green PE, brown PE, or a blend of these, or erythorbate, and stored under accelerated shelf life conditions. Oxidative stability was monitored by measuring conjugated dienes, peroxides (PV), and TBARS. From the PV values, kinetic data (peroxide formation constant [k], shelf life [SL], and activation energy [Ea]) and thermodynamic data (enthalpy, entropy, and Gibbs free energy) of lipid oxidation were estimated. All PE inhibited the formation of lipid oxidation more effectively than erythorbate. Lipid oxidation was characterized as a first-order reaction, following Arrhenius's Law. The reaction was also characterized as endothermic and nonspontaneous. Principal component analysis and cluster analysis elucidated the kinetic thermodynamic antioxidant mechanism of PE in controlling pâté oxidation by reducing k and increasing SL, Ea, enthalpy, and Gibbs free energy.