面筋蛋白粒子-黄原胶Pickering乳液的制备及其表征

制备黄原胶与面筋蛋白纳米粒协同稳的Pickering乳液,表征Pickering乳液的物理化学性能和微观结构。结果显示:通过黄原胶与面筋蛋白纳米粒协同作用,可制备出稳定性较好的Pickering乳液。低质量分数的黄原胶(0.2%)会促进乳析;当黄原胶质量分数不小于0.3%时,乳液于4℃贮存30 d仍无乳析现象;当黄原胶质量分数为1%时,贮存30 d乳液出现析油的现象。不同乳化顺序得到乳液的稳定性不同。乳液M-WG-XG(面筋蛋白纳米粒与玉米油乳化得粗乳液,然后加入黄原胶二次分散)的稳定性最好,同时乳液的平均粒径最小(21.4±0.314)μm。黄原胶的加入增大了乳液的净电荷,乳液的稳定性提高。共聚焦显微镜结果表明,乳液M-WG-XG液滴分布均匀,界面层呈现出多层结构。相比于其他方式制备的乳液,乳液M-WG-XG有更好的黏弹性和离子稳定性。

Preparation and Characterization of Wheat Gluten Nanoparticles-Xanthan Gum Pickering Emulsions

In this study, wheat gluten nanoparticles and xanthan gum were used to synergistically stabilize Pickering emulsions and their physicochemical properties and microstructure were characterized. The results showed that stable Pickering emulsions could be prepared through the synergism between xanthan gum and wheat gluten nanoparticles. While low concentration of xanthan gum (0.2%) promoted creaming, the emulsion could be stored for one month at 4 ℃ without any aggregation or creaming when the concentration of xanthan gum was equal to or greater than 0.3%. When the concentration of xanthan gum was 1%, the emulsion became unstable after 30 days. The emulsion stability varied with different orders of emulsification. The M-WG-XG emulsion (prepared by sequential dispersion of a mixture of wheat gluten nanoparticles and corn oil, followed by addition of xanthan gum) had the highest stability and smallest particle size (21.4 ± 0.314) μm. The addition of xanthan gum increased the net charge and consequently stability of emulsions. The droplets were evenly distributed and the interface layer exhibited a multilayer structure under confocal laser scanning microscopy. Compared to the other emulsions, the M-WG-XG emulsion possessed a better viscoelasticity and higher salt stability (0–1 000 mmol/L NaCl) against aggregation.