Emulsion stabilized by starch nanocrystals

The starch nanocrystals made use of in this study were prepared by sulfuric acid hydrolysis of wx maize starch. The stable oil-in-water emulsions of 50?vol% paraffin liquid were prepared by using starch nanocrystals as emulsifier when the weight percentage concentration of starch nanocrystal relative to water was above 0.02?wt%. The size of the droplets decreased with the raising of the concentration of starch nanocrystal. These emulsions were very stable to coalescence over months and the creaming of emulsions decreased with the increasing of starch nanocrystal concentration. The surface tension of starch nanocrystal dispersions was found decreased from 71.7 to 45.8?mN/m when the nanocrystal concentration grew from 0.05 to 3.0?wt%. This indicates that starch nanocrystals are surface active particles. Further tests on the emulsifying ability of supernatant of centrifuged starch nanocrystal dispersions and the emulsion stability at the melting temperature of starch nanocrystals confirmed that the emulsions were indeed stabilized by starch nanocrystals.