自由基法多酚共价结合对大豆蛋白基乳液凝胶特性的影响  

Effect of Covalent Conjugation with Polyphenols by Free Radical Method on Gel Properties of Soybean Protein-Stabilized Emulsion

作　　者：孟甘露 楚玉南 吴仪 王菊兵 金花[1] 许晶[1] MENG Ganlu;CHU Yunan;WU Yi;WANG Jubing;JIN Hua;XU Jing(College of Art and Science,Northeast Agricultural University,Harbin 150030,China;Mudanjiang Branch of Heilongjiang Academy of Forestry,Mudanjiang 157000,China)

机构地区：[1]东北农业大学文理学院,黑龙江哈尔滨150030 [2]黑龙江省林业科学院牡丹江分院,黑龙江牡丹江157000

出　　处：《食品科学》2024年第1期23-31,共9页Food Science

基　　金：黑龙江省重点研发计划项目(GA21B001)。

摘　　要：将阿魏酸(ferulic acid,FA)与大豆分离蛋白(soy protein isolate,SPI)通过自由基法共价结合后制备葡萄糖酸内酯(gluconolactone,GDL)诱导的乳液凝胶,探究FA自由基法共价结合对SPI结构、乳液特性、乳液凝胶特性的影响。通过大豆分离蛋白-阿魏酸(soy protein isolate-ferulic acid,SFA)乳液凝胶的分子间作用力、质构特性及持水性的分析,确定FA结合的最佳添加量为150μmol/g(相对于SPI质量)。在此条件下,光谱分析显示,FA对SPI有荧光猝灭作用,FA结合后SPI的β-折叠含量下降,α-螺旋含量、β-转角含量和无规卷曲含量上升。SFA乳液的Zeta电位绝对值、界面蛋白含量增大,平均粒径、表观黏度减小。SFA乳液凝胶的终存储模量(G’)升高,低场核磁共振测定中弛豫时间和峰比例变化表明SFA乳液凝胶水合特性更佳;SFA乳液凝胶具有更加均匀致密的多孔网络结构。结果显示,经150μmol/gFA自由基法共价结合的SPI具有制备乳液凝胶的应用价值。In this study,a covalent conjugate between ferulic acid(FA)and soybean protein isolate(SPI)was prepared by free radical method and was used to prepare gluconolactone(GDL)-induced emulsion gels.The effects of covalent binding to FA on SPI structure,emulsion properties and emulsion gel characteristics were investigated.The optimum concentration of FA was determined as 150μmol/g protein based on intermolecular forces,textural properties,and water-holding capacity of SPI-FA(SFA)stabilized emulsion gels.Under this condition,spectral analysis showed that FA had a fluorescence quenching effect on SPI,and after covalent binding to FA,a decrease in theβ-folded content and an increase in theα-helix,β-turn and random coil contents of SPI appeared.The absolute value of zeta potential and interfacial protein content of SFA stabilized emulsions increased,and the mean particle size and apparent viscosity decreased.The final storage modulus(G’)of SFA stabilized emulsion gels increased,and the changes in relaxation times and peak ratios observed in low-field nuclear magnetic resonance(NMR)measurements indicated that the SFA stabilized emulsion gels had better hydration properties.Moreover,they had a more uniform and dense porous network structure.These results show that SPI covalently bound to 150μmol/g protein of FA is valuable in the preparation of emulsion gels.

关 键 词：阿魏酸 多酚共价结合 大豆蛋白 凝胶性能 乳液凝胶 

分 类 号：TS214.2[轻工技术与工程—粮食、油脂及植物蛋白工程]