Study On High Internal Phase Pickering Emulsion And Foam Emulsion Stabilized By Chalaza

High internal phase Pickering emulsion(HIPE)refers to the volume fraction of the dispersed phase in the system >74% of a class of emulsions,which impart soft solid properties to liquid fats.Foam is a dispersive system formed by the gas phase dispersing in the continuous liquid or semi-solid phase,which is widely used in ice cream,milk foam and other products.In this study,HIPE and foam emulsion were successfully prepared using chalaza as food grade natural granule(CHA protein particles)emulsifier,can be applied to plastic fat products to reduce the hazards of trans acids produced by hydrogenation of fats in traditional production methods.The main research conclusions are as follows:The protein composition and some functional properties of the chalaza were investigated,and the protein changes under different aqueous phase p H and salt concentration were studied.The results showed that the main proteins in the chalaza are ovalbumin,ovotransferrin,ovummucinoid protein and lysozyme.When the p H value of the aqueous phase is 4.0(PI)/ salt ion concentration is 0.6M,CHA protein particles aggregate,which has amphiphilic,double wettability,good emulsifying stability and foam stability,and has the potential to be used as an emulsifier.A stable HIPE was prepared by using CHA protein particles as emulsifier and primary sunflower oil as oil phase.The structure of the emulsion was observed by microscopic observation.The effects of particle concentration,p H and salt ion concentration on the stability of the emulsion were investigated,the optimum preparation conditions of the emulsion were determined,and the highest stable oil phase volume was explored.The results show that the optimal conditions for preparing emulsion are as follows: particle concentration 1.5wt%,sodium chloride concentration 0.6M/p H4.0;microstructure clearly observed that CHA protein particles are effectively adsorbed and embedded on the oil-water interface,which plays a steric hindrance effect on emulsion coalescence.The emulsion type is O/W type,and the stable oil content can reach 85%.It is proved that CHA protein particles are a good emulsifier.At the same time,the rheological analysis results show that the emulsion has viscoelasticity and independent support,can convert liquid oil into viscoelastic soft solid,and has the potential to be used as a plastic fat template.Using CHA protein particles as emulsifier,primary sunflower oil as oil phase and xanthan gum as synergistic stabilizer,a stable foam emulsion was prepared,and the optimum raw material ratio was determined.The microstructure of the emulsion was observed by optical microscope,the effects of post-processing treatments on the stability of foam emulsion were observed,and the stability mechanism of foam emulsion was clarified.The results showed that the optimum raw material ratio was as follows: particle concentration 2.0wt%,oil phase volume fraction 40%.The foam emulsion prepared with 0.25wt% xanthan gum has the best foaming property and foam stability.Except for the instability of foam emulsion when p H is 2.0,the post-processing treatment has no significant effect on the stability of foam emulsion prepared at the optimum ratio.The results show that protein particles and xanthan gum can work together to stabilize bubbles and effectively prevent the aggregation or coarsening of bubbles.And it can replace the hydrogenated vegetable oil on the market and be used in milk foam products,so as to reduce the harm of hydrogenated vegetable oil to human body.