Surface-active solid lipid nanoparticles as Pickering stabilizers for oil-in-water emulsions.

摘要

Oil-in-water (O/W) emulsions solely stabilized by surface-active solid lipid nanoparticles (SLN) were developed. SLN were generated by quench-cooling hot O/W nanoemulsions consisting of 7.5% glyceryl stearyl citrate (GSC) dispersed in water. Their initial vol.-weighted mean particle diam. (approx. 152 nm) and zeta potential (ca. --49 mV) remained unchanged for 24 wk. O/W emulsions (oil phase vol. fraction: 0.2) containing 7.5% (w/w) GSC SLN in the aqueous phase were kinetically-stable for 12 wk and did not visually phase-separate over 24 wk. The O/W emulsions generated with solid-state GSC SLN had a vol.-weighted mean oil droplet diam. of approx. 459 nm and a zeta potential of ca. --43 mV. Emulsion microstructure evaluated with TEM revealed dispersed oil droplets sparsely covered with adsorbed Pickering-type SLN as well aggregated SLN present in the continuous phase. Gradual emulsion destabilization resulted from GSC SLN dissolution during the experimental timeframe. Overall, surface-active SLN developed via nanoemulsions effectively kinetically stabilized O/W emulsions. [This paper was presented at the Delivery of Functionality in Complex Food Systems Symposium held in Guelph, Canada, August 2011.]