乳清蛋白-鼠李糖脂混合生物乳化剂的性能研究

Study of the performance of mixed whey protein-rhamnolipid bioemulsifier

制备了不同比例组合的乳清蛋白和鼠李糖脂混合体系,对其乳化性质(0#柴油为底物烃)进行了研究。结果表明:同等质量浓度下,混合物表现出比单独乳清蛋白和鼠李糖脂更好的乳化活性,说明二者有很好的乳化协同作用,鼠李糖脂组分的增加还可以有效降低乳状液的平均粒径。研究了不同环境条件下混合体系的乳化活性,结果显示混合物在中性及碱性条件下拥有显著提高的乳化活性;乳清蛋白和鼠李糖脂质量比为2∶1和1∶1的混合物在1.5%和2.5%的氯化钠含量下也表现出显著提高的乳化活性;同时混合物对3种不同的底物烃均能有效乳化。对Zeta电位和界面性质进行了研究,发现相比于单一组分,混合物胶束粒子的负Zeta电势减弱,而少量鼠李糖脂的加入即可显著提高混合物的界面活性以及润湿性。

The mixed systems of whey protein and rhamnolipid at different ratios were prepared,and their emulsifying properties(0#diesel as a substrate hydrocarbon)were studied.The results showed that,at the same mass concentration,the mixture showed better emulsifying activity than pure whey protein or rhamnolipid,indicative of good emulsification synergism.The increase of rhamnolipid component therein can also effectively reduce the mean particle size of the emulsion.The emulsifying activity of the mixture under different conditions was studied,which showed that the mixture has significantly improved emulsifying activity under neutral and alkaline conditions;the mixtures of whey protein and rhamnolipid with mass ratio of 2∶1 and 1∶1 also show significantly improved emulsifying activity at 1.5%and 2.5%NaCl contents;Moreover,the mixture is effective in the emulsification of three different substrate hydrocarbons.The Zeta potential and interfacial properties are investigated.It was found that the negative Zeta potential of the mixed micelle particles is weakened compared with the individual components,and the addition of a small amount of rhamnolipid significantly increases the interfacial activity and wettability of the mixture.