Impact of Chelating Agent and Antioxidant on the Oxidative Stability of Soybean Oil-in-water E-mulsion Containing Iron

摘要

The oxidative stability of oil-in-water emulsion is supposed to be involved with the droplet size, the properties of emulsion droplet interface and the influence of prooxidants. For soybean oil added with arachidonic acid (AA) emulsion stabilized by whey protein, the influence of iron concentration, chelator and antioxidant on lipid oxidation during accelerated oxidation were examined. In order to get the better understanding of influence of the presence of iron in the emulsion on the oxidation, the physicochemical properties of emulsion have been explored. Particle size distribution showed that the emulsion droplets with the addition of ferrous sulfate became aggregated after homogenization, being obviously flocculation rather than coalescence. Lipid oxidation determined by secondary oxidative product marker TBARS indicated that iron was an important lipid oxidation catalyst in emulsion and the oxidation rate was greatly affected by chelating agent-sodium citrate. The preventive effect of antioxidant on oxidation occurred in the latter oxidative process to eliminate oxygen produced during the oxidative chain reaction.