Emulsion electrospraying and spray drying of whey protein nano and microparticles with curcumin

Abstract

This study describes the potential of nanoencapsulation of curcumin using the oil-in-water emulsion electrospraying technique. Whey protein was used as wall material, coconut oil was substituted as carrier material for curcumin and the emulsion was prepared at 1:200 and 1:500 core-to-wall (curcumin: whey protein) ratios through high-speed homogenization. Encapsulated micro and nanoparticles were produced by spray drying and electrospraying techniques, respectively, and the influence of both encapsulation processes and core-to-wall ratios on the physicochemical and functional stability of encapsulated curcumin was studied. At the 1:500 core-to-wall ratio, the resulting electrosprayed particles showed a smooth spherical shape with size in the nanoscale range (∼371 nm). Electrosprayed particles with a 1:500 core-to-wall ratio exhibited higher encapsulation efficiency with ∼88% retention of curcumin, around 1.08-fold higher than spray dried particles. Fourier transform infrared spectroscopy study explained the interactions of whey protein with coconut oil containing curcumin through hydrogen bonding and hydrophobic interactions. Interactions had a positive impact on the stability of encapsulated curcumin during simulated gastric and intestinal conditions. Solubility of the curcumin was enhanced in all encapsulated particles as observed through dissolution studies; in particular, electrosprayed particles showed higher dissolution behavior as compared to spray dried particles. Electrosprayed curcumin nanoparticles with a 1:500 core-to-wall ratio showed significant protection against degradation of curcumin under simulated gastric and intestinal conditions and had higher bioaccessibility (∼83%) than other formulations. Thus, the proposed study explains a promising strategy for the production of nanoencapsulated particles with enhanced stability of curcumin, and the results of this work can be extended to functional food applications.