Preparation Of Inulin-whey Protein Isolate/Anthocyanin Complex And Its Application In Pickering Emulsion System

Emulsion delivery systems are an effective method that can be used to encapsulate,protect and promote bioactive food ingredients.Protein particles are often used as one of the natural stabilizers of Pickering emulsions because of their amphiphilic properties,but they are unstable and easy to aggregate in hot and sour environments,which greatly limits their application in the food processing industry.In this paper,whey protein isolate(WPI)was selected as the research object,and the glycosylation reaction was modified by inulin with different degrees of polymerization to study the effects of glycosylated proteins with different degrees of polymerization on unsaturated oils and natural activities in Pickering emulsion system.The mechanism of stabilization of ingredients.At the same time,the bioactive substances encapsulated in the emulsion will still be degraded by the reactive oxygen species in the emulsion,while the antioxidant capacity of glycosylated proteins is limited and cannot completely prevent the degradation of curcumin.Antioxidant Pickering emulsions often use protein/polyphenol complexes as emulsion stabilizers.Later in this paper,the interaction between glycosylated proteins and cyanidin-3-O-glucoside(C3G)is used to form strong antioxidant capacity,Highly digestible and hypoallergenic complex,and acts as a stabilizer for the construction of curcumin-loaded Pickering emulsion delivery systems.The main findings are as follows:1.Preparation and characterization of glycosylated proteins with different degrees of polymerization.The degree of glycosylation was regulated by controlling the reaction time,and the effects of polysaccharides(inulin)with different degrees of polymerization on the process of glycosylation and the functional properties of its products were discussed.Glycosylated proteins were characterized by endogenous fluorescence analysis,Fourier transform infrared spectroscopy analysis,SDS-PAGE analysis,grafting degree analysis,Zeta potential analysis,analysis of emulsifying ability,differential scanning calorimetry,and antioxidant ability analysis.The results showed that short-chain inulin had a significant effect on the secondary structure and functional properties of whey protein isolate,while medium-chain and long-chain high-polymerization inulin was not easy to access protein structure and had little effect on protein functional properties.2.Glycosylated proteins with different degrees of polymerization improve the physicochemical stability and oxidative stability of pomegranate seed oil;through the analysis of surface tension and interfacial tension results,the surface tension and interfacial tension of WPI and short-chain inulin gradually decrease with the glycosylation reaction time,while medium-chain and long-chain high-polymerization inulin did not improve the interfacial properties of proteins;the stability of the emulsion was judged by measuring the particle size of Pickering emulsion.From the results,short-chain inulin glycosylated protein(glycosyl(72 h)(WPI-SCI(72 h))stabilized Pickering emulsion has the best stability;after accelerated oxidation,WPI-SCI(72 h)can effectively inhibit the formation of oil oxidation products;after accelerated oxidation,WPI-SCI(72 h)stabilized Pickering emulsion did not increase the harmful volatile components significantly,and could significantly inhibit the generation of harmful volatile components of oil.3.The effect of the interaction between glycosylated protein and C3 G on the physicochemical properties of protein such as antioxidant,digestibility and sensitization;under the characterization of particle size,potential and PDI,when the mass ratio was 2:1and p H 7.4 Glycosylated protein/C3 G composite particles under the most stable;from the results of Fourier transform infrared spectroscopy,C3 G has a significant impact on the secondary structure of glycosylated proteins,and the interaction between C3 G and glycosylated proteins is mainly are hydrogen bond interaction,CN stretching and NH bending;from the results of thermal stability and anti-oxidation,glycosylated protein/C3 G has the best thermal stability and anti-oxidative ability;from simulated stomach and intestine analysis From the results,glycosylated protein/C3 G has high resistance to intestinal and pepsin,which makes the digestion process slow;from the results of Western Blot and ELISA,the immunoglobulin(Ig E)of glycosylated protein/C3 G The content was the lowest,indicating that the glycosylation modification and the introduction of polyphenols can significantly reduce the sensitization of the protein.4.Construction of the curcumin-loaded glycosylated protein/C3 G Pickering emulsion system;the stability of the emulsion was judged by measuring the particle size of the Pickering emulsion.From the results,the glycosylated protein/C3 G stabilized Pickering emulsion had the most excellent performance.Stability;according to the pictures of CLSM,the glycosylated protein/C3 G stabilized emulsion is more evenly dispersed,and there is a thick protein adsorption layer around the emulsion droplets;from the results of the TSI stability analyzer,the sugar-based The glycosylated protein/C3 G stabilized curcumin-loaded Pickering emulsion has the smallest TSI index,and the stability of the emulsion is the best;the glycosylated protein/C3G-stabilized curcumin-loaded Pickering emulsion has the degradation retention rate during the storage period of 8 days.The largest,the longest degradation half-life,can effectively inhibit the degradation of curcumin.