Departamento de Ingeniería Química, Escuela Politécnica Superior, Universidad de Sevilla, c/ Virgen de África, 7, E41011 Sevilla, Spain.
Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, c/ P. García González, 1, E41012 Sevilla, Spain.
Int J Biol Macromol. 2020 Jun 15;153:747-754. doi: 10.1016/j.ijbiomac.2020.03.078. Epub 2020 Mar 11.
In this work, food-grade sunflower oil/W Pickering emulsions stabilized by xanthan gum-zein complex were developed. For this purpose, laser diffraction, rheological, multiple light scattering, confocal laser scanning microscopy (CLSM) and field emission scanning electron microscopy (FESEM) measurements were carried out. A response surface methodology was used to determine the optimized zein and oil concentration of the emulsion by using D and Turbiscan Stability Index (TSI) as objective functions to minimize. Subsequently, the optimized formulation with minimum D was selected and the biological macromolecule, advanced performance xanthan gum (APXG), was added. CLSM results of emulsions without gum showed the location of zein in the oil-water interface protecting droplets against coalescence as Pickering stabilizer. They also demonstrated that zein did not present important aggregation at the working pH. The addition of APXG changed the flow behaviour from Newtonian to shear thinning which fitted to the Cross model. This fact provoked the occurrence of viscoelastic properties and an increase in stability. FESEM results suggested the formation of a zein-gum complex, which forms a layer covering the droplets, protecting them against oxidation and physical destabilization. Therefore, this research supports the role of zein-APXG complex as a stabilizer of future emulsions.
在这项工作中，开发了由黄原胶-玉米醇溶蛋白复合物稳定的食品级葵花籽油/W 型 Pickering 乳液。为此，进行了激光衍射、流变学、多重光散射、共焦激光扫描显微镜 (CLSM) 和场发射扫描电子显微镜 (FESEM) 测量。使用 D 和 Turbiscan 稳定性指数 (TSI) 作为目标函数，使用响应面法确定乳液的优化玉米醇溶蛋白和油浓度，以最小化。随后，选择具有最小 D 值的优化配方，并添加生物大分子、先进性能黄原胶 (APXG)。没有胶的乳液的 CLSM 结果表明，玉米醇溶蛋白在油水界面处的位置作为 Pickering 稳定剂保护液滴免受聚结。它们还表明，玉米醇溶蛋白在工作 pH 值下没有重要的聚集。APXG 的添加使流动行为从牛顿型变为剪切稀化，符合 Cross 模型。这一事实引发了粘弹性的产生和稳定性的增加。FESEM 结果表明形成了玉米醇溶蛋白-胶复合物，该复合物形成了覆盖液滴的层，保护它们免受氧化和物理失稳的影响。因此，这项研究支持了玉米醇溶蛋白-APXG 复合物作为未来乳液稳定剂的作用。
