Fabrication Of Pickering Emulsions Stabilized By Wheat Gluten Nanoparticles-Xanthan Gum And Their Beta-Carotene Loading Capacity

Colloidal particle-stabilized Pickering emulsions have attracted considerable interest in recent years due to their superior stability against coalescence and irreversible adsorption to the oil-water interface.With the increasing demand for green,safe and sustainable commodities,it is of great economic importance to explore green and safe food-grade Pickering emulsion stabilizers.Proteins and polysaccharides are natural food ingredients that can be used as stabilizers for Pickering emulsions.Proteins have good emulsification,but poor pH stability and ionic stability.Moreover,polysaccharides have high temperature resistance,alkali resistance and acid resistance,but their emulsification is poor.Emulsions stabilized by protein-polysaccharide have better stability and interfacial properties.In this paper,wheat gluten nanoparticles and xanthan gum were used to synergistically stabilize Pickering emulsions.The physicochemical properties and microstructure of Pickering emulsion were characterized.Its application in stability and nutrient transport was studied.The results were as follows:(1)We demonstrate firstly prepared wheat gluten nanoparticles via a simple pH cycling method,particle size was 220.3 ± 2.13 nm,dispersion coefficient was 0.22,ζ-potential was 21.06 ± 0.30 mv.Storage stability,p H stability,and ionic stability of wheat gluten nanoparticles were investigated.Studies have shown that p H4.0 gluten protein nanoparticles have better storage stability and can be used as an emulsifier for Pickering emulsions.(2)A simple and low-cost shear emulsification technique was used to prepare a Pickering emulsion stabilized by xanthan gum and wheat gluten nanoparticles.The effects of preparation method of xanthan gum and gluten protein nanoparticles on the stability of the emulsion were investigated.The interfacial structure,the distribution and aggregation behavior of protein colloidal particles were studied by confocal microscopy.The effect of the emulsification method on the structure of the emulsion was clarified.The results showed that the addition of xanthan gum improved the storage and ionic stability of the emulsion,and the effect of different emulsification methods were different.The emulsification method also affects the rheological properties of the emulsion.The M-WG-XG emulsion(the gluten protein nanoparticles and corn oil emulsified in the crude emulsion and then the secondary dispersion of the xanthan gum)had the best storage stability,ionic stability and rheological properties.Therefore,M-WG-XG emulsion was chosen to encapsulate β-carotene.(3)The β-carotene-loaded xanthan gum and gluten-protein stabilized Pickering emulsion(WG-XG)were successfully prepared.The results showed that the loading of β-carotene did not change the microstructure and stability of the emulsion.Xanthan gum and wheat gluten nanoparticles synergistically stable Pickering emulsions have excellent storage stability,p H stability,ionic stability,thermal stability and digestive properties.The addition of xanthan gum enhanced the retention and bioavailability of β-carotene.