玉米醇溶蛋白/藻酸丙二醇酯/小分子乳化剂三元复合胶体颗粒稳定β-胡萝卜素Pickering乳液机理研究

Pickering emulsions produced by the alcohol-soluble protein particles alone are prone to creaming. Therefore, the design of composite colloidal particles to stabilize Pickering emulsions has been the research hotspot in food fields. The application of Pickering emulsions stabilized by zein-based composite colloidal particles as delivery systems for functional components is lack of systematic investigation. Zein, propylene glycol alginate and natural small molecule emulsifiers (soy lecithin, rhamnolipid, Quillaja bark saponins) are selected as materials in this project. The ternary components interactions in aqueous ethanol solution are explored, and the formation mechanism of ternary composite colloidal particles is revealed. The orientational modulation and control for particle properties are achieved by adjusting the parameters of calcium ions induction. The ternary composite colloidal particles are applied to prepare β-carotene loaded Pickering emulsions, verify the key factors affecting the stability of Pickering emulsions by detecting the properties of composite colloidal particles, and reveal the stabilization mechanism of Pickering emulsions formed by the composite colloidal particles. The in vitro and in vivo digestion and absorption characteristics of β-carotene in Pickering emulsions are evaluated and controlled-release models are established in this project. Implementation of this project will provide a scientific basis for the application of Pickering emulsion stabilized by ternary composite colloidal particles as a delivery system of nutraceuticals.

单一醇溶蛋白质颗粒制备的Pickering乳液易呈分层现象，构建复合胶体颗粒用于稳定Pickering乳液已成为目前食品领域的研究热点。基于玉米醇溶蛋白的复合胶体颗粒制备Pickering乳液及其在传递功能因子方面的应用尚缺乏系统研究。本项目以玉米醇溶蛋白、藻酸丙二醇酯和天然小分子乳化剂（大豆卵磷脂、鼠李糖脂、皂树皂苷）为材料，探究三元组分在乙醇水溶液中相互作用规律，揭示三元复合胶体颗粒生成机制；调节钙离子诱导参数实现颗粒特性定向调控；采用三元复合胶体颗粒制备β-胡萝卜素Pickering乳液，探明三元复合胶体颗粒特性影响Pickering乳液稳定性的关键因素，阐明三元复合胶体颗粒稳定Pickering乳液的机理；探究Pickering乳液中β-胡萝卜素的体内/外消化吸收特性并构建其控释模型。本项目的实施可为三元复合胶体颗粒稳定的Pickering乳液在功能因子稳态化领域应用提供科学依据。

以玉米醇溶蛋白三元复合胶体颗粒为稳定剂，制备负载β-胡萝卜素Pickering 乳液尚缺乏系统研究。本项目以玉米醇溶蛋白、藻酸丙二醇酯和天然小分子乳化剂为原料，使用反溶剂共沉淀和乳化-蒸发等方法构建三元复合胶体颗粒，系统探究三元组分互作规律对复合胶体颗粒形成机制、理化性质和功能特性的影响，以实现对单、双功能因子的稳态包埋和高效递送；揭示金属离子（K+、Ca2+）诱导对三元复合胶体颗粒理化特性的定向调控机制；探究三元复合胶体颗粒特性影响Pickering乳液稳定性的关键因素，重点阐明三元复合胶体颗粒对Pickering乳液理化稳定性、界面特性和β-胡萝卜素生物可及性的调控机制。研究结果表明，在pH4.0下，玉米醇溶蛋白和藻酸丙二醇酯能够通过静电相互作用、氢键和疏水相互作用形成复合胶体颗粒，小分子乳化剂的添加改变了玉米醇溶蛋白在不同溶剂（颗粒水分散液或乙醇水溶液）中的疏水微环境和二级结构。复合胶体颗粒的微观结构、表面特性和理化稳定性取决于所加入小分子乳化剂的浓度。由玉米醇溶蛋白-藻酸丙二醇酯复合胶体颗粒和鼠李糖脂共稳定的Pickering乳液在不同环境应力（光、热、pH 和离子强度）下保持稳定，由低浓度小分子乳化剂和胶体颗粒共稳定的Pickering乳液表现出更好的物理稳定性。由胶体颗粒和小分子乳化剂组成的致密界面层有效地降低了Pickering乳液游离脂肪酸的释放，同时降低了β-胡萝卜素生物可及性。本项目的实施将对开发新型多功能食品配料，实现功能因子稳态与控释具有重要意义，并为三元复合胶体颗粒稳定Pickering乳液在功能因子稳态化领域应用提供科学依据。