Effect of lipophilized gallic acid on the oxidative stability of omega-3 fatty acids rich soy and cow milk

Abstract

The antioxidant and interfacial effects of gallate alkyl esters on the oxidative stability of fish oil-enriched cow milk (CM) and soymilk emulsions (SM) stored at 4 °C were evaluated. The peroxide value and volatile compounds were also measured to monitor the progress of lipid oxidation. Despite the higher amount of unsaturated fatty acids, the SM emulsion showed a considerable increase in the oxidative stability compared to CM emulsion. It was found that reducing chlorogenic acid content may contribute to the lipid oxidation of SM emulsions. Moreover, the results showed that the antioxidant efficiency of gallates had a positive correlation with their partitioning at the oil-water interface. Octyl gallate followed by propyl gallate with the same partition at the interface had the highest antioxidant effect in protecting SM and CM emulsions. In contrast, short and long-chain gallates showed a higher lipid oxidation due to the higher partitioning into the aqueous and oil phases.