Antioxidant properties of ferulic acid-based lipophenols in oil-in-water (O/ W) emulsions

Butyl ferulate (BF) and octyl ferulate (OF) were investigated to enhance oxidative stability of 1.0% vegetable oil-in-water (O/W) emulsions at pH 3.5 and 7.0 at different concentrations (5, 10, 15, 20, and 25 mg/L of emulsion). Particle size distribution, droplet surface charge, hydroperoxides (PV), hexanal and nonanal were monitored for 14 days at 35 degree celsius. Higher concentrations of BF and OF generated smaller particles at pH 7.0 but not at pH 3.5. Control showed the highest negative surface charge (-58.38 +/- 0.31 mV, pH 7.0) compared to BF and OF (-46.71 +/- 0.06 mV at levels >0.10 mg/L). Both alkyl ferulates counteracted lipid oxidation, especially at pH 3.5, where PV decreased up to 96% compared to the control and delayed hexanal and nonanal formation. A low content of lipophenols allowed to achieve a tremendous shelf-life extension, demonstrating that BF and OF could be of great interest for food application.