大豆伴球蛋白(7S)在远离等电点热处理，会自组装成淀粉样蛋白纤维。本研究旨在开发7S自组装纤维在水包油乳液中的应用潜力。研究采用7S在pH 2.0条件下85 ℃热处理3 h，通过动态光散射（DLS）、硫磺素T荧光（Th T荧光）和原子力显微镜(AFM)观察，表明制备短棒状蛋白自组装纤维。利用未热处理的7S与热处理得蛋白纤维为稳定剂，研究了蛋白浓度(c)和油相比例(?)对乳化活性和储藏稳定性的影响。实验表明，c≥2.0%，蛋白纤维的乳化活性显著高于未热处理的7S；这可能因为蛋白纤维的线性结构具有更好的构象柔顺性，能高效的吸附在油水界面。c =6.0%，d4,3在? =0.2~0.6范围不受?的影响。c ≥4.0%，蛋白纤维的乳化稳定性显著优于未热处理的7S，且相对低聚合率(CI)及脂肪上浮率(CI%)，使蛋白纤维表现出皮克林稳定剂的性质。这一发现为皮克林颗粒的制备提供了一种新的方式。

Soy β-conglycinin (7S) can self-assemble into amyloid-like fibrils with heat treatment, at a pH distant from the isoelectric point. The aim of this study was to investigate the potential application of 7S self-assembled fibrils in oil-in-water emulsions. 7S was heated at 85 ℃ for three hours (pH 2.0). The product was analyzed by dynamic light scattering (DLS), thioflavin T (Th T) fluorescence assay, and atomic force microscopy (AFM). The results indicated that short, rod-shaped, self-assembled fibrils were successfully prepared. The influence of protein concentration (c) and oil fraction (?) on the emulsifying activity and storage stability were studied using unheated 7S as well as 7S fibrils obtained from heat treatment as stabilizers. The results showed that at c ≥ 2%, the emulsifying activity of 7S-fibril was significantly higher than that of unheated 7S, which is probably since the linear fibrillar structure exhibits higher conformational flexibility and 7S-fibril can be effectively adsorbed onto the oil-water interface. At c = 6%, the droplet size (d4,3) was not affected by the ? value within the range of 0.2 to 0.6. At c ≥ 4.0%, 7S-fibril showed much higher emulsifying stability than unheated 7S along with relatively low coalescence index (CI) and creaming index (CI%) as compared to unheated 7S. Thus, 7S-fibril exhibited the properties of Pickering stabilizer. The results of this study indicate a new approach for the preparation of Pickering-like stabilizer.

国家自然科学基金资助项目（31171632）