【作者】 连子腾； 王欢； 江连洲；

【Author】 Lian Ziteng;Wang Huan;Jiang Lianzhou;College of Food Science,Northeast Agricultural University;

【机构】 东北农业大学食品学院；

【摘要】 从蛋白柔性角度出发,探究琥珀酰化大豆分离蛋白(SPI)结构特征-蛋白柔性-理化性质之间的互作机制,制备乳液和乳液凝胶体系,明晰蛋白柔性与乳液界面之间构效关系,解析琥珀酰化和多糖浓度对乳液凝胶特性的影响机理。琥珀酰化通过改变SPI二级和三级结构,增加分子柔性,进而影响其理化性质。琥珀酸酐(SA)添加量为15%时达到最佳。随着SA添加量的增加,SPI在油/水界面吸附能力增强,乳液粒径减小,界面吸附能力和宏观稳定性改善,吸附过程中SPI结构展开和重排使构象柔性进一步增加,提高了乳液稳定性。琥珀酰化和海藻酸钠(Alg)浓度增加,改善了乳液凝胶的质构性质,分子刚性结构被破坏,形成以静电作用和氢键为主的凝胶网络,乳液凝胶对槲皮素递送性能增强且具有良好胃肠缓释效果。Alg含量为2%最佳,持水力达91.37%,生物可及性74.54%和化学稳定性66.81%。本研究明确了蛋白柔性在乳液稳态及乳液凝胶形成中所起作用,为营养素递送提供新思路。更多还原

【Abstract】 The aim of this work was to investigate the interactions between the structural features-protein flexibility-physicochemical properties of succinylated soybean protein isolate(SPI) from the point of view of protein flexibility;to prepare emulsion and emulsion gel systems,to clarify the conformational relationship between the protein flexibility and emulsion interface,and to further analyze the influence mechanisms of succinylation and polysaccharide concentration on the properties of the emulsion gels.Succinylation affected the physicochemical properties by increasing the molecular flexibility through changed in the secondary and tertiary structure of the SPI.Succinic anhydride(SA) addition was optimal at 15%.With the SA addition,the adsorption capacity of SPI at the oil/water interface was enhanced,the emulsion particle size decreased,and the interfacial adsorption capacity and macroscopic stability were improved.The unfolding and rearrangement of SPI structure during the adsorption process further increased the conformational flexibility and improved the emulsion stability.Succinylation and increased concentration of sodium alginate(Alg) improved the textural properties of the emulsion gels and the molecular rigidity structure was disrupted to form a gel network dominated by electrostatic interaction and hydrogen bonding.The emulsion gels showed enhanced delivery properties and excellent gastrointestinal slow release of quercetin.Alg concentration of 2% was optimal with water holding capacity of 91.37%,bioaccessibility and chemical stability of 74.54% and 66.81%.This study will deepen the understanding of the role of protein flexibility in emulsion homeostasis and emulsion gel formation,and provide new ideas for nutrient delivery.更多还原