Physicochemical characteristics and stability of oil-in-water emulsions stabilized by OSA starch

Starch hydrophobically modified with octenyl succinic anhydride (OSA starch) has strong surface activity and capability to modify viscosity of continuous phase. The influences of OSA starch, used as emulsifier, on stability, disperse and rheological properties of oil-in-water emulsions were examined in this work. The oil content in emulsions varied from 5 to 60% and OSA starch concentrations were 8, 10, 12, 14 and 16% expressed relative to the water mass. The obtained results showed that increase in OSA starch concentration led to decrease in mean droplets diameter (d(32)) and decrease in standard deviation. Also, apparent viscosity and physical stability of the systems increased with increase in OSA starch concentration. For all examined concentrations of OSA starch the increase in amount of dispersed phase caused increase in apparent viscosity and non-Newtonian behavior of emulsions became more pronounced. A significant delay of creaming at high oil concentrations in emulsions stabilized by OSA starch was noticed. (C) 2012 Elsevier Ltd. All rights reserved.