Enhancing emulsion stability and performance using dual-fibrous complexes: Whey protein fibrils and cellulose nanocrystals

Edible proteins can self-assemble into fibrils, which can improve their performance as emulsifiers. However, they are limited in some food applications. We prepared whey protein isolate fibril-cellulose nanocrystal complexes (WPIF-CNC) by electrostatic complexation. The stabilities of emulsions prepared using either WPIF or WPIF-CNC were compared to evaluate the effect of complexation on emulsion formation and properties. Moreover, the potential of the emulsions to act as delivery systems for curcumin was investigated. WPIF and CNC were found to complex by hydrogen bonding, hydrophobic, and electrostatic interactions. The complexes formed were good Pickering stabilizers in oil-in-water emulsions. Emulsions formulated using the complexes were more resistant to creaming than those stabilized by WPIF. The complexes were able to form self-supporting gelled emulsions at 70 % oil concentration, which protected curcumin from photo- and thermal-degradation. Consequently, dual-fibrous complexes may have application in the food industry as novel emulsifiers for the creation of nutraceutical delivery systems.