超声波改性大豆蛋白乳液凝胶的制备、性能及应用

Preparation, properties and applications of ultrasonic modified soy protein emulsion gels

摘要:

采用超声波改性的大豆蛋白作为乳化剂和凝胶基质制备葡萄糖酸内脂（GDL）诱导乳液凝胶，研究超声波处理对大豆蛋白乳液和乳液凝胶特性，以及槲皮素运载性能的影响。通过乳液凝胶分子间作用力和质构特性的分析，确定超声波改性的最佳条件，为超声波功率400 W，温度55 °C，时间30 min。结果表明，超声波改性导致乳液的平均粒径下降、Zeta-电位绝对值上升、界面蛋白含量上升、表观粘度下降。乳液凝胶的最终G’值提高，形成了更趋近于弹性性质的凝胶材料；低场核磁共振中驰豫时间降低，峰比例分布改变，乳液凝胶的水合特性上升；微观结构观察发现，改性大豆蛋白乳液凝胶具有更加均匀的多孔结构，油滴更好地嵌入在凝胶的网络结构中。此外，超声波处理改善了大豆蛋白乳液凝胶的运载性能。实验结果表明，超声波改性大豆蛋白槲皮素乳液凝胶的包封率、生物利用率和脂肪分解率显著提高。

Abstract:

In this paper, ultrasonic modified soy protein was used as emulsifier and gel matrix to prepare soy protein emulsion gel induced by glucono-δ-lactone (GDL), and the effects of ultrasonic treatment on the emulsion and emulsion gel properties of soy protein and the transport properties of quercetin were investigated. Through the analysis of intermolecular interaction and texture properties of emulsion gel, the optimized ultrasonic conditions were determined, which were ultrasonic power 400 W, temperature 55 °C, and time 30 min. The test results showed that the ultrasonic modification destroys the hydrophobic interaction inside the protein, exposes the hydrophobic groups, and increases the charged groups, led to a decrease in the average particle size of the emulsion, an increase in the absolute value of the Zeta-potential, an increase in the interface protein content, and a decrease in the apparent viscosity. After the ultrasonic modification treatment, the final G'value of the soy protein emulsion gel increases, and the degree of gelation gradually increases, forming a gel material that is closer to elastic properties; the relaxation time in low-field NMR decreased, the peak ratio distribution changes, the hydration characteristics of the emulsion gel increase, and the ability of the dense gel structure to bind water molecules is enhanced. At the same time, microscopic observations showed that the modified soybean protein emulsion gel had a more uniform porous structure, and the oil droplets were better embedded in the network structure of the gel. In addition, ultrasonic treatment improved the transport properties of soy protein emulsion gels. The experimental results showed that the encapsulation rate, bioavailability and lipolysis rate of ultrasonically modified soy protein quercetin emulsion gels were significantly improved. The ultrasonic modification treatment has laid a theoretical foundation for the development of a protein emulsion gel delivery system with excellent performance.