ass日本风韵熟妇pics男人扒开女人屁屁桶到爽|扒开胸露出奶头亲吻视频|邻居少妇的诱惑|人人妻在线播放|日日摸夜夜摸狠狠摸婷婷|制服 丝袜 人妻|激情熟妇中文字幕|看黄色欧美特一级|日本av人妻系列|高潮对白av,丰满岳妇乱熟妇之荡,日本丰满熟妇乱又伦,日韩欧美一区二区三区在线

With the aim to reveal the interaction between soybean protein isolates (SPI) and dextran (Dex) in the mixed system and the effect of dextran concentration (1%, 3%, 5% and 7%) on the structure and functional properties of SPI, fluorescence spectrum, ultraviolet spectrum and Fourier transform infrared spectrum were used to characterize the conformational changes of the SPI-Dex non-covalent polymer, and the effect of dextran concentration on the functional properties of SPI was analyzed through particle size, surface hydrophobicity, turbidity, solubility, emulsification activity, emulsification stability and antioxidant activity. The results showed that SPI and Dex can interact through two noncovalent forces: hydrophobic interaction and hydrogen bond under neutral conditions, thereby changed the structure and functional properties of SPI. The addition of Dex can prevent the exposure of tryptophan and tyrosine residues, and form a tighter tertiary structure compared with SPI alone. When the addition of Dex in the mixed system was less than 5%, with the increase of Dex, the particle size, surface hydrophobicity, and turbidity of SPI-Dex polymer were decreased significantly, and the solubility, emulsification, and antioxidant activity of SPI-Dex polymer were improved significantly. When the concentration of Dex in the mixed system was 5%, the improvement effect on the functional properties of SPI was the most significant, the solubility, emulsifying activity index and antioxidant activity of SPI were increased by 16.35%, 18.71% and 11.30%, respectively.