Department of Food Science, Northeast Agricultural University, Harbin, Heilongjiang, 150030, China.
National Soybean Engineering Technology Research Center, Harbin, Heilongjiang, 150030, China.
J Food Sci. 2021 May;86(5):1737-1750. doi: 10.1111/1750-3841.15688. Epub 2021 Apr 6.
This study examined the effects of different sequential treatments of dextran glycation and succinic anhydride acylation on the structure and physicochemical properties of soy protein isolate (SPI). The tested properties included electrophoresis (SDS-PAGE), Fourier transform infrared spectroscopy, endogenous fluorescence spectroscopy, surface hydrophobicity (H ), free sulfhydryl (-SH), solubility, interfacial properties, rheological properties, and scanning electron microscope (SEM). The results show that the two treatments significantly improved the structure and functional characteristics of the SPI. The order of the methods had an important effect on the SPI. The lowest H (231.76 ± 11.92), the highest free -SH content (3.09 ± 0.09 µmol/g), and the highest solubility at pH = 7 (77 ± 3.97%) were obtained when the acylation treatment was followed by the glycation treatment. Emulsification, emulsion stability, foaming, and foam stability were also the highest. Glycation and acylation caused the viscosity coefficient (k) of the SPI solution to decrease compared with SPI alone, but the flow index (n) value increased, and the sum G' value of the conjugate system decreased as gel time increased. SEM showed that its microstructure has changed significantly. Therefore, this research provided an effective method for improving the functional characteristics of SPI and had potential industrial application prospects. PRACTICAL APPLICATION: Glycation and acylation of soybean protein isolate improved the chemical modification method of protein, improved the functional properties of soybean protein, widened its application in food and materials, and provided a new idea for the further development and utilization of soybean protein.
本研究考察了葡聚糖糖化和琥珀酸酐酰化的不同顺序处理对大豆分离蛋白（SPI）结构和物理化学性质的影响。测试的性质包括电泳（SDS-PAGE）、傅里叶变换红外光谱、内源性荧光光谱、表面疏水性（H）、游离巯基（-SH）、溶解度、界面性质、流变性质和扫描电子显微镜（SEM）。结果表明，两种处理方法显著改善了 SPI 的结构和功能特性。方法的顺序对 SPI 有重要影响。当酰化处理后进行糖化处理时，H 值最低（231.76±11.92）、游离 -SH 含量最高（3.09±0.09µmol/g）、pH=7 时溶解度最高（77±3.97%）。乳化、乳化稳定性、起泡和泡沫稳定性也最高。糖化和酰化导致 SPI 溶液的粘度系数（k）与单独的 SPI 相比降低，但流动指数（n）值增加，并且共轭体系的总和 G'值随着凝胶时间的增加而降低。SEM 显示其微观结构发生了明显变化。因此，本研究为提高 SPI 功能特性提供了一种有效的方法，具有潜在的工业应用前景。实际应用：大豆分离蛋白的糖化和酰化改善了蛋白质的化学修饰方法，提高了大豆蛋白的功能特性，拓宽了其在食品和材料中的应用，为进一步开发和利用大豆蛋白提供了新的思路。
