Novel stable pickering emulsion based solid foams efficiently stabilized by microcrystalline cellulose/chitosan complex particles

Abstract

In order to increase the stability of the food foam system, microcrystalline cellulose (MCC) and chitosan (CHN) were used as stabilizer based on Pickering effect. The MCC/CHN colloidal particles had the initial morphology of MCC, the addition of CHN had an obvious influence on the surface zeta potential of the MCC, and it indicated that there was a strong interaction between MCC and CHN, which had been proved by using FTIR results. The MCC/CHN colloidal particles had typical shear thinning and elastic gel-like behaviors, and the Pickering emulsions stabilized by using the MCC/CHN colloidal particles also had the similar rheology properties. The pH had an obvious effect on the stability and emulsifying ability of the Pickering emulsions, and when the pH was near to 7.0, the emulsions had gelation behavior and there were inter-droplet interactions in the emulsion systems. For practical application, the solid foams were prepared from the Pickering emulsions at pH 7.0. The obtained foams had porous structure, and the molecular weight of the CHN had an influence on the strength of the foams, the energy absorption of the foams was increased from 17.66 kJ/m3 to 32.86 KJ/m3with the increase of the molecular weight of the chitosan from 200 mPa s to 400 mPa s. The results indicated that MCC/CHN colloidal particles could be used to prepare food-grade solid foams through Pickering emulsions, which had great potential to produce safe, clean, and green products.