Tailored zein-polysaccharide nanoparticles for anthocyanin encapsulation: Insights into preparation and characterization

Encapsulation is a promising strategy to increase the physicochemical stability of anthocyanins (ACNs). In this work, red cabbage anthocyanins-loaded composite nanoparticles were prepared by the self-assembly of zein protein and anionic polysaccharides . Three anionic polysaccharides and two types of preparation approaches were used to form different ACNs-loaded zein/polysaccharide nanoparticles . Results revealed that ACNs-loaded zein/polysaccharide nanoparticles showed spherical morphology with an average particle size in the range of 102.6–360.4 nm, polydispersity index of 0.214–0.415, zeta potential of - (26.7–42.6) mV and the total ACNs encapsulation efficiency (EE) of 68.03–80.55 %, depending on the type of polysaccharides and the different adding sequences of the raw materials. Polysaccharides coating increased the EEs of ACNs as compared to the zein alone. ACNs monomers with acylated groups presented higher EEs. ATR-FTIR spectrum indicated hydrogen bonds , hydrophobic and electrostatic interactions were the dominant forces among ACNs, zein and polysaccharides. In addition, ACNs-loaded zein/polysaccharide nanoparticles showed good colloidal stability to different pH, ionic strength and storage conditions as compared to ACNs-loaded zein nanoparticles due to the electrostatic and steric repulsion from the polysaccharide coating on the nanoparticle surface.