Preparation And Stability Study Of Walnut Protein-Polysaccharide Complex Pickering Emulsion

As one of the world’s walnut production countries,walnut resources are very rich,and because of its rich nutritional value,loved by the majority of consumers.But at present for walnut processing research mainly focuses on walnut oil and walnut protein,and every year walnut meal produced in the process of walnut oil processing for only a small amount of walnut protein powder,milk drinks,more primary products are abandoned,causing the utilization of walnut protein and low added value,failed to realize the high value utilization of resources,caused a serious waste of protein resources.At the same time,with the continuous improvement of people’s living standards,people pay more and more attention to the healthy diet and nutrition.Most trans fatty acids in processed foods come from partially hydrogenated oils(PHOs).As a new type of stable emulsion system,Pickering emulsion has been proved to be used to produce various foods as a margarine or salad dressing substitute,and has gradually become the focus of many scholars with its strong interface stability and high added value.In this study,we will try to use food as a substitute for margarine or salad dressing by combining walnut protein with polysaccharide and studying its.The main study results are as follows:(1)Using alkali soluble acid sedimentation method to extract walnut protein and polysaccharide after building composite rack system,through the walnut protein solubility,foaming and foaming stability of walnut protein-polysaccharide composite system preparation process is: walnut protein constant concentration of 1%,yellow gum concentration 0.2%,walnut protein solubility can reach 96.8%,composite system foaming and foaming stability also reached the maximum value.(2)Using univariate test and response surface test,the best process parameters of preparing walnut protein-polysaccharide pickering emulsion were determined as follows: polysaccharide concentration was0.2% and oil percentage was 72%.Through the optimal analysis of emulsion chromatography index at p H6.5,walnut protein-polysaccharide composite pickering emulsion with stable system and low chromatography index was prepared.(3)The walnut protein-polysaccharide composite system of the composite particle-stabilized pickering emulsion was prepared by vacuum freeze-drying to represent the Pickering emulsion stability by contact angle measurement,light microscopy and confocal microscopy.At the same time,the influence of different preparation conditions on the emulsion was explored,and the storage stability of the emulsion showed good thermal stability and refrigeration stability.(4)Walnut paste products were prepared on the basis of Pickering emulsion and compared with commercially available salad dressing.Explore the potential and possibility of Pickering lotion as an alternative to salad dressing by comparing the rheology with commercially available salad dressing.The comparative analysis shows that the viscosity curve of walnut dressing based on Pickering lotion presents almost parallel results to the viscosity curve of salad dressing,which shows the consistency of the shear and dilution characteristics of walnut dressing and salad dressing,and also proves the possibility that Pickering lotion can replace salad dressing.