超声波辅助7S-麦芽糊精接枝反应的响应面法优化

Optimization of Ultrasound-assisted 7S-maltodextrin Graft Reaction by Response Surface Methodology

以脱脂豆粕为原始材料,分离纯化得到β-伴大豆球蛋白(7S)。采用超声波辅助技术对7S与麦芽糊精进行接枝改性。以改性产物乳化活性(EAI)和乳化稳定性(ESI)为指标,采用Box-Behnken模型对工艺条件进行优化,并对改性前后的蛋白样品进行了SDS-PAGE电泳和电镜扫描(SEM)分析测定,验证7S与麦芽糊精发生糖基化反应。结果表明优化后得到的最佳改性条件为:麦芽糊精添加量9.5%,超声波处理时间30 min,超声波处理功率450 W,在此条件下平均乳化活性为1.142,平均乳化稳定性为27.13 min,相对天然未改性7S球蛋白分别提高了60.59%和57.06%。

Defatted soybean meal was employed as an original material to get 13-conglycinin （7S） through separation and purification. And 7S was grafted with maltodextrin by using ultrasound-assisted to modify its properties. Taking the emulsifying activity （EAI） and emulsion stability （ESI） of the modified products as indexes, Box-Behnken model was used to optimize reaction conditions. In addition, SDS- PAGE electrophoresis and scanning electron microscope （SEM） analysis were also investigated to verify that 7S molecule was grafted with the saccharide molecule. Response surface analysis revealed that the optimized modified conditions were as follows： the amount of maltodextrin of 9.5% , ultrasound time of 30 min, ultrasound power of 450 W. On these conditions, the emulsifying activity index （EAI） and emulsion stability index （ESI） reached to 1. 142 and 27.13 min, which were 60.59% and 57.06% times against the native β-conglycinin, respectively.