Fabrication of protein-stabilized nanoemulsions using a combined homogenization and amphiphilic solvent dissolution/evaporation approach

Oil-in-water nanoemulsions containing small lipid droplets (d < 100 nm) are finding increasing applications within the food industry as delivery systems in transparent foods and beverages, and to increase the bioavailability of lipophilic active agents. In this study, we show that nanoemulsions can be fabricated from food-grade ingredients (corn oil, whey protein, and water) using simple processing operations (homogenization, dilution and solvent evaporation). Nanoemulsions were formed by homogenizing 10 wt% organic phase (corn oil and ethyl acetate) with 90 wt% aqueous phase (water and whey protein isolate). The mean particle diameter of the emulsions decreased with increasing ethyl acetate concentration in the organic phase, which was attributed to its ability to alter the size of the droplets produced during homogenization, as well as its ability to be removed from the droplets by dissolution and/or evaporation after homogenization. The particle size also decreased with increasing emulsifier concentration. These nanoemulsions may be useful as delivery systems in the food, pharmaceutical and cosmetics industries.

Graphical abstractSchematic drawing of the formation of nano-sized oil droplets by controlled diffusion or evaporation of ethyl acetate (EA) from corn oil droplets.Figure optionsDownload full-size imageDownload as PowerPoint slide