Study On Emulsifying Properties Of Soy Hull Polysaccharide Hydrolyzed With Different Enzymes

The structure of polysaccharides is of great significance to the function of polysaccharides.Our previous studies showed that Soy Hull Polysaccharides(SHP)have excellent emulsification activity,but the structure-activity relationship between the structure and emulsification is still unclear.Therefore,the purpose of this study mainly includes :(1)the effects of different structural regions of SHP on emulsification;(2)the role of the binding protein in the emulsification process;(3)The emulsion with more stable properties was prepared by controlling the interfacial composition,which provided a research basis for the subsequent commercial application.Firstly,the effects of different glycosidase hydrolysis on the emulsifying properties of SHP were studied.The SHP were hydrolyzed by endo-pectinase(PE)and endo-rhamnosidase(RE)for different time.The SHP and hydrolyzed SHP product were used to prepare emulsion.Then various instruments were used to characterize the differences in the properties of different samples,and the stability of the emulsion stabilized by them was investigated.It was found that the hydrolysis and destruction of different structure regions of SHP would decrease its emulsification until it could not completely cover the droplet stabilized emulsion.The longer the destruction time was,the worse the emulsification effect would be.The results showed that after hydrolysis for different times,the particle size,?-potential,apparent viscosity,amorphous crystallinity,surface structure,spatial conformation were decreased and the hydrophilicity was enhanced,which resulted in the decrease of its original emulsifying activity.Secondly,the emulsification of protein components of SHP was studied by using acidic protease and neutral protease to regulate the protein state at the interface under different p H.The SHP were hydrolyzed by protease for 10 min,30min,1H and 3H,and then used as emulsifier to prepare emulsion respectively.The properties of different SHP samples were investigated and the stability of emulsion was studied.It was found that the emulsification of SHP was the strongest after hydrolyzed by acid protease for 1H at p H3.0.The p H combined with protease treatment changed the existing state of protein components at the interface,affected the structure and spatial conformation of SHP,and prepared a more stable emulsion.At p H4.5,the protein molecules were aggregated,and the hydrophilic groups were exposed,which reduced the interfacial amphiphilicity of SHP.Hydrolysis by neutral protease at p H7.0 resulted in non-coexistence of protein and the chain of SHP at the interface due to electrostatic repulsion,loss of adsorption anchor points and reduced emulsification.In conclusion,the emulsification of soybean seed coat polysaccharides depends on the structure of its own chain as well as the protein components.The ?-potential,space steric hindrance of RG-? area,continuous phase viscosity,senior of sugar chain conformation,protein components are deeply affect the emulsification of SHP.