State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, PR China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, PR China.
School of Food Science and Technology, Jiang University, Wuxi 214122, PR China.
Colloids Surf B Biointerfaces. 2019 May 1;177:550-558. doi: 10.1016/j.colsurfb.2019.02.020. Epub 2019 Feb 13.
The effect of the adsorption behavior of soy proteins hydrolysates and monoglycerides on the properties of the film at oil-water interfaces in emulsions and emulsion stability was investigated. Surface tension, adsorbed protein composition and interfacial rheological properties were measured to gain insights into the relationships between molecular composition and properties. The interfacial film formed by 7S (β-conglycinin), 11S (Glycinin) and native soy protein isolate (NSPI) exhibited high elasticity due to a high concentration of adsorbed β-subunits, acidic and basic subunits. Soy protein isolate hydrolyzed by pepsin (SPHPe) and soy protein isolate hydrolyzed by papain (SPHPa) had a high percentage of small peptides, less β-subunits and acidic subunits, forming a fluid-like interfacial film at the beginning of the time sweep. Commercial soy protein isolate (CSPI) film without main soy protein subunits induced fluid-like properties. Monoglycerides displaced the small peptides, acidic and basic subunits from the interface and led to fat globule destabilization after 24 h aging. Emulsions were stable with 7S and SPHPe with high proportion of β-subunits, which were not replaced by monoglycerides. This study provided the foundation for the preparation and application of soy protein isolate with different emulsion stability requirements paired with selected enzyme treatments.
研究了大豆蛋白水解物和单甘酯的吸附行为对乳液和乳状液稳定性中油水界面处膜性能的影响。测量表面张力、吸附蛋白组成和界面流变性能，以深入了解分子组成与性能之间的关系。由 7S（β-伴球蛋白）、11S（大豆球蛋白）和天然大豆蛋白分离物（NSPI）形成的界面膜由于高浓度的吸附β-亚基、酸性和碱性亚基而具有高弹性。胃蛋白酶水解的大豆蛋白分离物（SPHPe）和木瓜蛋白酶水解的大豆蛋白分离物（SPHPa）具有较高比例的小肽，β-亚基和酸性亚基较少，在时间扫描的开始形成类似流体的界面膜。没有主要大豆蛋白亚基的商业大豆蛋白分离物（CSPI）膜诱导出类似流体的性质。单甘酯将小肽、酸性和碱性亚基从界面置换出来，并导致脂肪球在 24 小时老化后失稳。具有高比例β-亚基的 7S 和 SPHPe 乳液稳定，单甘酯不会置换这些亚基。这项研究为具有不同乳化稳定性要求的大豆蛋白分离物的制备和应用提供了基础，可根据需要选择酶处理方法。
