Involvement of Chelating Action and Viscosity in the Antioxidative Effect of Xanthan in an Oil/Water Emulsion

Abstract

The antioxidative effects of xanthan and other polysaccharides were evaluated by measuring the Fe²⁺-induced consumption of oxygen dissolved in the oil/water emulsion. The degree of oxygen consumption was, from the lowest, in the order of xanthan <pec-tin <guar gum &le; tragacanth gum, and was closely related to the Fe²⁺-binding ability of the polysaccharides. The oxygen consumption was also affected by the viscosity of the aqueous solution in the emulsion, but not by the oil-droplet size. The antioxidative mechanism for xanthan can be accounted for primarily by its high metal-binding ability, and additionally by its viscous behavior.