Study On The Preparation Of Gluten-based Flour Improver

After absorbing water, gluten formed the wet gluten with dense three-dimensionalnetwork structure, which could improve the viscoelasticity, liposuction and other properties ofthe dough. So adding gluten could improve the quality of wheat flour. However, due to poorwater dispersibility of gluten, it was ineffective to add it to wheat flour directly, so it was notwidely used in flour products industry. In this paper, a gluten-based flour improver with gooddispersion stability and high activity, namely the polysaccharide-gluten complexes, wasprepared to improve the water dispersibility of gluten. The product had some advantagessuch as food safety, ease and significant effect in use, which laid the foundation for improvinggluten performance and utilization efficient in flour.Firstly, dispersion stability of wheat gluten were characterized by different methods suchas visible light absorbance method, intuitive sedimentation, viscosity method; the feasibilityof visible light absorbance method to characterize gluten dispersion stability was verified.Onthe basis of above, this study characterized dispersion stability of gluten by visible absorbancevalue and optimized the production of polysaccharide-gluten complex in hot and humidconditions. On the basis of single factor tests, orthogonal experiments were adopted todetermine the optimal technological conditions of this production. The results showed that themost suitable reacting conditions are as follows: the polysaccharide was pectin, solid-liquidratio1:10, gluten/pectin (w/w)40:1, pH4.5, temperature40°C, reacting time60min. Underthe optimum conditions, the dispersion stability of the complex reached86.89%, and thedispersion was improved significantly.Secondly, fourier transform infrared spectroscopy (FTIR) and SDS-PAGE were used toanalyze the preliminary structure of pectin-gluten complexes. The changes-OH and-NHabsorption peak position in Infrared absorption spectra, indicating that the bonding in pectinand gluten occurred in hydrogen bonding between the-NH and-OH. By SDS-PAGE patterns,pectin-gluten soluble complexes were derived from the selected cross-link between pectin andmedium molecular weight hydrophobic gluten protein. Compared with untreated gluten, thesolubility of pectin-gluten compound under neutral conditions increased nearly five times.And the compound still maintained high flexibility, extensibility and water retention etc,which could meet the application requirements of professional gluten.Finally, the pectin-gluten was added to wheat flour to study the quality of dough and thequality and processing characteristics of noodles. When adding3%complexes, the wet glutencontent in dough, water absorption, dough development time, dough stability time, silty indexwere improved by19.7%,3.7%,311.8%,260.0%and285.7%respectively by comparing withblank control, and the weakening degree of flour were lower than40.8%of the control. When adding3%pectin-gluten complex suspension in normal flour to make noodles, the qualityindex of noodle such as hardness, chewiness, the maximum shear stress, tensile strength,noodles sensory score, were improved by38.7%,18.3%,11.0%,63.3%,22.0%respectivelyby comparing with blank control and water absorption, cooking loss was reduced by22.4%,15.2%. When the noodles were cooked cured, the noodles containing pectin-glutencomplexes had significant anti-softening effect. After soaking10min, swelling index,hardness, chewiness, the maximum shear stress, tensile strength were66.2%,117.1%,119.3%,163.3%,133.8%of the control. It could be concluded, pectin-gluten complexes whichproducted in this experiments improved gluten quality and utilization, and had excellentimprovement for the quality of flour and noodles. Pectin-gluten complexes was an excellentand efficient flour improver.