Study On The Wheat Gluten Modified By Polyacrylic Acid Sodium And Potato Acetate Starch

This project took wheat gluten protein (gluten powder) as the research object, polyacrylicacid sodium(PAANa) and potato acetate starch were selected as gluten fortifier to study thewater-holding capacity (WHC) and the rheological property such as viscoelastic modulus,creep and recovery properties of gluten powder, determination of SH/S-S, fourier transforminfrared spectroscopy(FI-IR), differential scanning calorimetry apparatus(DSC), scanningelectron microscope(SEM) study were used to analyze the secondary structure,thermodynamic properties and microscopic structure changes of before and after themodification of wheat gluten protein. Main contents stated below:Salt ratio(Na2CO3:K2CO3), salt adding quantity, alkali(NaOH) adding quantity, glutenfortifier adding quantity and mixing time these five factors were selected to analyze theinfluence of WHC and viscoelastic modulus of gluten protein modified by that two kinds ofgluten fortifiers, and to respectively identify the optimal process conditions of gluten fortifiersprotein being modified the two kinds of gluten fortifiers in the two types of indicators. Resultsshows that WHC and viscoelastic modulus of gluten protein prepared under the optimumtechnological condition were significantly increased, and the effect of modification of PAANawas better than that of potato acetate starch.WHC and viscoelastic modulus as for indexes, the wheat gluten protein modified byPAANa and potato acetate starch in optimal conditions were respectively marked as PWM,PMM, TWM, TMM, the unmodified wheat gluten protein sample marked as P, microstructurewas carried out on the wheat gluten protein were determined, the method of Ellman’sdetermination of SH/S-S concluded that the SH content order of the tested protein sampleswas P> TWM> PWM> TMM> PMM, and that the S-S content order was P＜TWM＜PWM＜TMM＜PMM, and thus reflected the modified protein samples were combined with amore solid structure; Through the FT-IR spectrums showed that the secondary structure of Phad β-fold structure as the main characteristics, but not containing random coil, while thesecondary structure of PWM, PMM, TMM were changed to that α-helix structure disappeared,and the random coil was turned up, and TWM changed little, which showed that theconformation of polypeptide chain folding had some changes, the modified wheat gluten had more solid structure and gluten throws enhanced; Auxiliary DSC scans showed that PWM’sTd rised slightly, but the heat enthalpy change ΔH had bigger changes, and there had been nosignificant changes in the TWM, Td of PMM and TMM had larger changes, but the twosamples of ΔH basically remained unchanged, which showed that PAANa had a greatermodificate effect to wheat gluten protein than the potato acetate starch, and the bound watercontents of modified protein samples were decreased, and forces between the structureincreased, which further proved that structures of wheat gluten protein samples modified bythe two gluten fortifiers were more close, reflecting thews enhancement from the side; FinallySEM was used to see the microstructure of modified samples, the order of the test sampleholes was P> TWM>PWM> TMM> PMM, proving structures of wheat gluten proteinsamples modified by the two gluten fortifiers were more uniform solid once again from themacro validation, and the thews of wheat gluten been improving.