Fabrication and characterization of low-fat Pickering emulsion gels stabilized by zein/phytic acid complex nanoparticles

Pickering emulsion gels (PKEGs) are being explored as solid fat substitutes and delivery systems due to their semi-solid textures and high stabilities. However, these PKEGs have relatively high-fat content, which is undesirable for nutritional and cost reasons. Therefore, in this study, low-fat PKEGs (10 % oil content) were successfully fabricated using zein/phytic acid (ZPA) complex nanoparticles with zein to phytic acid mass ratio of 1:0.006. These nanoparticles have a mean diameter of around 161 nm and wettability of around 89°. The formation of PKEGs were confirmed by the results of dynamic rheology (G' > G″). Confocal laser scanning microscope showed that the complex nanoparticles formed a dense barrier on the surface of the oil droplets, which prevented the oil droplets against coalescence. The chemical stability of curcumin was greatly improved by encapsulation in the PKEGs. The low-fat PKEGs developed in this study may be effective delivery systems for hydrophobic bioactive substances.