Study On The Emulsion Stabilizing Effect Based On The Interaction Between Sarcoplasmic Protein And Xanthan Gum

Sarcoplasmic protein is a kind of co-produced substance in the process of separating myofibrillar protein from minced meat of livestock and poultry,which has great economic value.However,there is little research on its functional properties,especially the oil-water interface.Using interaction,between protein and polysaccharide,to improve the functional properties of the complex system is a common regulatory idea in the food industry.When the protein and polysaccharide solution is mixed in proportion,different systems may form one phase or two phases according to the protein and polysaccharide molecular characteristics,the composition of the solution and the environmental conditions.Xanthan gum was chosen as the polysaccharide in this study.Because xanthan gum and sarcoplasmic protein have the same charge,when the concentration of the system exceeds a certain level,the electrostatic repulsion or steric hindrance is stronger than the equilibrium effect,resulting in phase separation between them.In this paper,we first describe the properties of the sarcoplasmic reticulum oil-water interface,and further construct the protein polysaccharide composite emulsion through the interaction between sarcoplasmic protein and polysaccharide complex.Our results will provide technical reference for the rational utilization of sarcoplasmic protein.1.Oil-water interfacial properties of sarcoplasmic protein in different meatIn order to explain the scientific relationship among the protein structure(hydrophobicity,molecular flexibility,etc.),dynamic conformation changes in interfacial adsorption and system energy of sarcoplasmic proteins,then explored the function of sarcoplasmic proteins.Pork,fish and chicken as raw materials(raw meat were chosen according to the proportion of carcass and research value),the oil-water interface properties and intrinsic scientific links between indicators of different meat(livestock,poultry and fish)sarcoplasmic proteins were characterized by the determination of their basic physical and chemical indexes,composition,conformation,emulsification and interfacial properties.The results showed that the chicken sarcoplasmic protein had high content of phenylalanine and tyrosine while the particle size and surface hydrophobicity were also significantly higher than those of pork and fish sarcoplasmic proteins(P<0.05).There was no significant difference in the change rate of protein conformation between pork sarcoplasmic protein and chicken sarcoplasmic protein(P>0.05)within the same time,but there was significantly slower in fish sarcoplasmic protein(P>0.05).Compared with pork and chicken sarcoplasmic protein,the diffusion rate on the interface of fish sarcoplasmic protein was significantly higher(P<0.05)but no significant difference between chicken and pork sarcoplasmic protein(P>0.05).The emulsifying activity of fish sarcoplasmic protein was significantly lower than that of pork and chicken sarcoplasmic protein(P<0.05),and the emulsifying stability of fish sarcoplasmic protein was the worst among the three sarcoplasmic proteins(P<0.05).Principal component analysis showed that the pork and chicken meat sarcoplasmic protein had similar properties,and they two were significantly different compared with fish muscle sarcoplasmic protein.The emulsifying activity and emulsifying stability of sarcoplasmic protein was strongly correlated with the surface hydrophobicity,ζ potential and conformational change rate,and the diffusion rate had strong correlation with solubility.2.Study on the water phase complex of sarcoplasmic protein and xanthan gumIn this chapter,0%,0.5%,1%,1.5%and 2%sarcoplasmic protein were mixed with 5%xanthan gum solution respectively in water phase to study the effect of sarcoplasmic protein concentration on the properties of the composite system.It was found that the turbidity of the complex decreased with the increase of protein concentration in the complex system of different proportions of myoplasma protein and xanthan gum,indicating that the small molecule filling effect of sarcoplasmic protein is beneficial to reduce the aggregation degree of the system;the concentration of protein has a dose-effect relationship with the particle size of myoplasma protein xanthan gum complex and the viscosity of the system.Compared with xanthan gum itself,with the increase of sarcoplasmic concentration,the average particle size in the solution gradually decreases;when the concentration of sarcoplasmic is 0.5%,the viscosity of the system reaches the maximum value,and then continues to increase the protein concentration,the viscosity of the system gradually decreases.The concentration of supernatant protein in the sarcoplasmic-xanthan gum system also gradually increases with the increase of sarcoplasmic content due to phase separation caused by supersaturation.3.Effect of sarcoplasmic protein-xanthan complex on emulsion stabilityIn this chapter,the sarcoplasmic protein-xanthan complex,which was studied in the second chapter,was made into an emulsion and stability of emulsion of complex was studied.It was found that with the increase of sarcoplasmic protein,continuous phase xanthan gum resulted in rejection flocculation of the whole system and increased the viscosity.However,when myosin concentration reached 1%,the viscosity of the system reached the maximum,and when myosin concentration continues to increase,the viscosity of the system decreased gradually.In the process of the change of sarcoplasmic protein concentration,the droplet size of the emulsion did not change too much,indicating that the fresh emulsion could completely envelop the droplets in the presence of xanthan gum under the concentration of these sarcoplasmic proteins.The change of the emulsion potential indicates that some interaction existed between xanthan gum and myosin,resulting in the formation of sarcoprotein xanthan complex.The macroscopic and microscopic analysis of the emulsion showed that under the presence of xanthan gum,the different concentration of sarcoplasmic protein also had a certain effect on the emulsion stability of the system,and 2%of the milk protein concentration did not produce oil floatation,which was relatively stable.