Chemical hardening of gliadin nanoparticles alters their oil-water interfacial behaviour. (October 2021)

• Record Type: Journal Article
• Authors: Petker, Katherine; Rogers, Michael A.; Joye, Iris J.
• Is Part Of: Food structure. Volume 30(2021)
• Publication Date: 2021-10
• Subjects: GNP gliadin nanoparticle -- LAS liquid anti-solvent precipitation; Gliadin nanoparticles -- Glutaraldehyde -- Oil-water interface -- Interfacial rheology -- Emulsion; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; Food -- analysis -- Periodicals; Food -- Analysis; Periodicals; 664.07
• DOI: 10.1016/j.foostr.2021.100218
• Languages: English
• ISSNs: 2213-3291

Abstract

Graphical abstract: Highlights: Chemical hardening reinforced gliadin nanoparticle (GNP) matrices. Viscoelastic films require particles to deform and interact at the interface. Hardened GNPs formed less coherent viscoelastic interfacial films. Untreated GNPs stabilized emulsions with a continuous particle network. Emulsions with hardened GNPs had more discontinuous oil droplet flocs. Abstract: In this study, the structure-function relationship of gliadin nanoparticles (GNPs) was probed by examining the behaviour of untreated and chemically hardened GNPs at oil-water interfaces. Particle size measurements showed that particles treated with glutaraldehyde demonstrated stability to disintegration in aqueous ethanol (70 v/v%), while untreated GNPs appeared to break apart into smaller particle fragments under these conditions. Air-water and oil-water tensiometry revealed that interfaces made with untreated GNP dispersions had higher dilational viscoelastic moduli than what was observed for glutaraldehyde-treated GNP dispersions. More and/or stronger interactions between adsorbed untreated GNPs at the interface seemed to form more cohesive viscoelastic interfacial films. Observation of the microstructure of emulsions with cryo-scanning electron microscopy revealed a tighter packing of oil droplets with more bridging between droplet interfaces in emulsions made with untreated GNP dispersions. These results suggest that the deformability of colloidal untreated GNPs and the increased mobility of their constituting proteins play an important role in their ability to rearrange and interact at the oil-water interface to form a strong viscoelastic film. Furthermore, the flexibility of protein particles is essential for the interaction between adsorbed particles and those in the continuous phase to form a protein network between neighbouring oil droplets.