影响豌豆蛋白乳化特性的分子机制

Study on the molecular mechanism of the effects on emulsifying properties of pea proteins

为了解豌豆蛋白的乳化特性及影响其乳化特性的分子机制,实现豌豆蛋白的高效应用,以豌豆蛋白粉为原料,与大豆油用高压均质法制备乳液,测定豌豆蛋白的乳化能力及稳定性,并考察其在乳液中的界面吸附特性及组分的竞争吸附。结果表明,在蛋白浓度1.0~30.0 mg/mL时,随着蛋白浓度的增加,界面吸附蛋白量显著上升,蛋白聚集体在竞争吸附中失去优势,7S和11S球蛋白的占比逐渐提高,乳液粒径降低,且乳化能力和稳定性增强;蛋白浓度≥20.0 mg/mL时,乳液平均粒径低至1.06μm,蛋白界面吸附趋于饱和状态,且7S球蛋白在竞争吸附中占明显优势,11S球蛋白次之,聚集体占比较低,且略低于原蛋白组成。

The emulsifying properties of pea proteins and the molecular mechanism that affected the emulsifying properties were investigated in this study. The pea protein powder was used to prepare emulsions using soy bean oil by homogenizing technique. The parameters of the emulsions were studied including the emulsifying property, stability, interfacial adsorption property and the competitive adsorption of components of pea proteins. The results indicated that when the protein concentration was within 1 to 30 mg/mL, with the increasing of concentration, the particle size of emulsions was decreasing, the emulsifying property and stability improved, and protein aggregates were losing the superiority in competitive adsorption, while the proportion of vicilin and legumin increased. When the protein concentration was higher than 20 mg/mL, the average diameter of oil droplets was lower than 1.06μm, the interfaeial adsorption of pea proteins would reach the saturation state. While there were more vicilin than legumin in surface proteins, whenthe proportion of aggregates was very low, which was less than the initial pea protein composition.