The role of emulsification strategy on the electrospinning of β-carotene-loaded emulsions stabilized by gum Arabic and whey protein isolate

Abstract

This work was aimed to systematically assess the effect of diverse emulsification strategies, i.e., layer-by-layer (LbL), directly mixing (DM), and heteroaggregation (HA) assemblies on electrospinnability of emulsions stabilized by gum Arabic (GA)-whey protein isolate (WPI) blend and their subsequence potential in β-carotene (BC) encapsulation. The designed BC emulsions were characterized in terms of zeta-potential, droplet size, and rheological properties. According to the results, LbL-formulated emulsions possessed the highest zeta-potential; however, HA-produced ones appeared to be more viscous among all emulsions. Properties of electrospun nanofibers varied considerably relying on either the emulsification strategy or the oil phase volume fraction as confirmed by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and fourier transform infrared specroscopy (FTIR). It was found that the resulting nanofibers produced by LbL and HA emulsification guaranteed higher BC encapsulation efficiency (>90%), in comparison to that of DM-engineered samples offering a lower efficiency of ∼71 %. The storage stability of BC emulsions stabilized with WPI-GA blend was in the order of LbL > HA > DM emulsions. Most importantly, the application of LbL assembly exhibited the most thermally/physicochemically stable carotenoid-comprising nanofibers among all studied mixing techniques. These results offer useful information for applications of different emulsification strategies for fabricating BC-loaded nanofibers via emulsion electrospining technique.

Keywords: Directly mixing; Electrospinning; Gum Arabic; Heteroaggregation; Layer-by-layer; β-carotene.