This study demonstrated the use of ultrasound-assisted extraction to render aqueous extract polyphenolic compounds from olive leaves. Sodium caseinate-olive leaf extract complexes were produced using different amounts of olive leaf extract (0, 0.5, 1, 1.5, and 2% w/v). Turbidity, solubility, antioxidant activity (DPPH and ABTS assays), foaming capacity and stability and surface hydrophobicity tests were done on each sample. To study the interaction mechanisms and structural changes, fluorescence, and Fourier-transform infrared were performed. Oil-in-water emulsions of the complexes were prepared and analyzed for their emulsifying properties (emulsifying activity index and emulsifying stability index), rheological properties and viscosity. Addition of olive leaf extract at higher amounts (1.5 and 2%) enhanced the turbidity, water solubility, antioxidant activity, and foam capacity/stability of protein-polyphenol complexes. Moreover, it was found that non-covalent interactions mainly hydrogen bonds were the main interaction mechanism of sodium caseinate/ olive leaf extract complexes. Surface hydrophobicity of complexes decreased with increasing amount of olive leaf extract. In terms of emulsion formation, the activity and stability increased with increasing the concentration of olive leaf extract. Addition of olive leaf extract also slightly increased the viscosity and viscoelastic parameters (storage and loss modulus).

这项研究证明了使用超声辅助提取从橄榄叶中提取水合多酚类化合物的方法。使用不同量的橄榄叶提取物（0、0.5、1、1.5和2％w / v）生产酪蛋白酸钠-橄榄叶提取物复合物）。对每个样品进行浊度，溶解度，抗氧化活性（DPPH和ABTS测定），起泡能力和稳定性以及表面疏水性测试。为了研究相互作用机理和结构变化，进行了荧光和傅立叶变换红外光谱。制备了配合物的水包油乳液，并对其乳化性能（乳化活性指数和乳化稳定性指数），流变性和粘度进行了分析。较高含量（1.5％和2％）的橄榄叶提取物的加入可提高蛋白-多酚复合物的浊度，水溶性，抗氧化活性和泡沫容量/稳定性。此外，发现酪蛋白酸钠/橄榄叶提取物复合物的主要相互作用机理主要是氢键。随着橄榄叶提取物含量的增加，复合物的表面疏水性降低。就乳液形成而言，活性和稳定性随橄榄叶提取物浓度的增加而增加。添加橄榄叶提取物也会略微增加粘度和粘弹性参数（存储和损耗模量）。