添加菊粉条件下的豌豆分离蛋白乳化特性研究

Emulsifying Properties of Pea Protein Isolate with Inulin

为探究添加不同质量分数(1%、3%、5%和7%)菊粉(Inulin,INU)对豌豆分离蛋白(Pea protein isolate,PPI)乳化性及乳液稳定性的影响,以PPI作为乳化剂,采用高压均质法制备了PPI/INU乳液,通过zeta电位测定、粒径测定、激光共聚焦显微镜(CLSM)、酶标法和内源荧光光谱等技术对乳液进行表征。结果表明:添加1%INU后,乳液具有最大zeta电位绝对值(为34.03 mV)和最小平均粒径(d4,3为395.50 nm);CLSM显示,低浓度(质量分数1%和3%)的INU使乳液液滴分布更均匀;INU质量分数为1%时,分别使PPI的乳化活性指数、乳化稳定性指数和乳液界面蛋白吸附率增加了7.8%、22%和11%;荧光光谱显示,随着INU浓度的增加,连续相中PPI-INU复合物的生成量增多,对乳液的稳定性产生了负面影响。由此说明低浓度(质量分数为1%和3%)的INU可改善PPI的乳化性、提高PPI乳液的稳定性,其中添加1%INU效果最显著。

Aiming to investigate the effects of different inulin(INU)concentrations(1%,3%,5%and 7%)on the emulsification of pea protein isolate(PPI)and its emulsion stability,and determine the optimal concentration of INU.PPI/INU emulsion was prepared by high pressure homogenization method using PPI as emulsifier.The emulsion was characterized by particle size,zeta potential,laser confocal microscopy(CLSM),enzyme labeling and endogenous fluorescence spectroscopy.The results showed that low concentrations(1%and 3%)of INU had a beneficial effect on zeta potential and average particle size,with an absolute maximum zeta potential at 1%INU(34.03 mV)and a minimum mean particle size(d4,3 was 395.50 nm).CLSM showed more uniform droplet distribution in emulsions with low concentrations(1%and 3%).When the concentration of INU was 1%,the emulsification activity index and emulsion stability index of PPI were increased by 7.8%and 22%,respectively,emulsion interface protein adsorption rate was increased by 11%.The fluorescence spectrum showed that with the increase of concentration of INU,the amount of PPI-INU complexes in the continuous phase was increased,which had a negative impact on the stability of the emulsion.It was concluded that low concentrations(1%and 3%)of INU could significantly improve the emulsification of PPI and enhance the stability of PPI emulsion,with 1%of INU being the most significant.