Influence of β-glucan extracted from hull-less barley on droplet characterization, stability and rheological properties of soy protein isolate stabilized oil-in-water emulsions.

In this study the effect of ultrasonically extracted β-glucan from hull-less barley (UBG, 0.25-0.75% w/w) on soy protein isolate (SPI, 4-12% w/w) stabilized oil-in-water emulsions was investigated. The results indicated that with increasing UBG concentration, zeta potential, droplets' specific surface area and emulsion stability increased; whereas, the surface and interfacial tensions, Sauter mean diameter (D 3,2 ) and the De Brouckere Mean Diameter (D 4,3 ), span value and creaming index decreased. Non-Newtonian shear-thinning (pseudoplastic) behavior was observed for oil-in-water emulsions stabilized by UBG. With increase in UBG and SPI concentrations, emulsion's flow behavior index ( n ) and consistency coefficient ( k ) increased and decreased; respectively. At all UBG and SPI concentrations, emulsions stored at 4 °C were more stable.