Study On Whey Protein Stabilization Pickering Emulsion And Application In Dairy Products

Whey protein,as a by-product of cheese,has been studied and explored,and has important applications in food industry and biomedicine.In this paper,by studying the effects of different protein concentrations and heat varying temperatures on the Pickering emulsion of whey protein,the basic process and process of preparing the stable Pickering emulsion of whey protein were determined.Through thermal denaturation of whey protein at different concentrations at different temperatures,the results showed that in the emulsion with sodium dodecyl sulfonate(SDS),when the protein concentration(80℃ heat treatment)exceeded 4%,the size of the emulsion decreased with the increase of concentration.With the increase of heat treatment temperature,the average particle size of the emulsion also increases and flocculation occurs.The emulsifying activity and emulsifying stability of the whey protein stabilized Pickering emulsion were improved.With the increase of protein concentration(2%,4%,6%,8%),the stability of the emulsion also improved.With the same protein concentration,the higher the thermal denaturation temperature,the more stable the emulsion.During the emulsion storage period,there was a great relationship between the temperature of thermal denaturation and the concentration of protein:compared with the control group,the sample group with high temperature of thermal denaturation showed an improvement in the floating of fat.The effects of preemulsification of whey protein on the structure and function of reprocessed cheese were studied.The 4%,8%,12%and 16%butter were preemulsified,which made the processed cheese have higher hardness,cohesion and masticability.The surface hydrophobicity of cheese samples decreased with the increase of emulsification degree.With the increase of emulsification degree,the microstructure of cheese observed by SEM was more uniform and denser.Confocal microscopy(CLSM)showed that the fat was more evenly distributed as the emulsification increased.With the decrease of free fat content,the tensile and melting properties of preemulsified cheese decreased slightly.This study shows that preemulsification can effectively inhibit the accumulation of fat and improve the stability of reprocessed cheese during storage.The drying of Pickering emulsion spray with high oil content into high oil whey powder has a great influence on the characteristics of high oil whey powder:the particle size increases,and with the increase of oil content,the particles observed by CLSM and SEM are larger and more complete;solubility is improved;The surface oil content was lower than that of the control group,indicating that the efficiency of embedding oil droplets with whey protein particles in Pickering emulsion was improved.The stability of high oil whey powder was improved,and the stability was the best with oil content of 25%.With the increase of oil content,the stability gradually deteriorated.