College of Food Science and Engineering, Jilin Agricultural University, Changchun, Jilin 130118, China; National Engineering Research Center for Wheat and Corn Deep Processing, Changchun, Jilin 130118, China.
College of Food Science and Engineering, Jilin Agricultural University, Changchun, Jilin 130118, China; National Engineering Research Center for Wheat and Corn Deep Processing, Changchun, Jilin 130118, China.
Food Res Int. 2024 Aug;189:114571. doi: 10.1016/j.foodres.2024.114571. Epub 2024 May 27.
The non-covalent and covalent complexes of ultrasound treated soybean protein isolate (SPI) and soybean isoflavone (SI) were prepared, and the structure, physicochemical properties and in vitro digestion characteristics of SPI-SI complexes were investigated. Ultrasonic treatment increased the non-covalent and covalent binding degree of SPI with SI, and the 240 W ultrasonic covalent complexes had higher binding efficiency. Appropriate ultrasonic treatment caused more uniform particle size distribution, lower average particle size and higher surface charge, which enhanced the free sulfhydryl groups and surface hydrophobicity, thus improving the stability, solubility and emulsifying properties of complexes. Ultrasonic treatment resulted in more disordered secondary structure, tighter tertiary conformation, higher thermal stability and stronger SPI-SI covalent interactions of complexes. These structural modifications of particles had important effects on the chemical stability and gastrointestinal digestion fate of SI. The ultrasonic covalent complexation had a greater resistance to heat-induced chemical degradation of SI and improved its chemical stability. Furthermore, the 240 W ultrasonic covalent complexes showed lower protein digestibility during digestion, and provided stronger protection for SI, which improved the digestion stability and antioxidant activity. Therefore, appropriate ultrasound promoted SPI-SI interactions to improve the stability and functional properties of complexes, which provided a theoretical basis for the development of new complexes and their applications in functional foods.
超声处理大豆分离蛋白（SPI）和大豆异黄酮（SI）的非共价和共价复合物被制备，并且研究了 SPI-SI 复合物的结构、物理化学性质和体外消化特性。超声处理增加了 SPI 与 SI 的非共价和共价结合程度，并且 240 W 超声共价复合物具有更高的结合效率。适当的超声处理导致更均匀的粒径分布、更低的平均粒径和更高的表面电荷，从而增强了自由巯基和表面疏水性，从而提高了复合物的稳定性、溶解度和乳化性能。超声处理导致更无序的二级结构、更紧密的三级构象、更高的热稳定性和更强的复合物中 SPI-SI 的共价相互作用。这些颗粒的结构修饰对 SI 的化学稳定性和胃肠道消化命运具有重要影响。超声共价复合化对 SI 的热诱导化学降解具有更大的抵抗力，提高了其化学稳定性。此外，240 W 超声共价复合物在消化过程中表现出较低的蛋白质消化率，并为 SI 提供了更强的保护，从而提高了消化稳定性和抗氧化活性。因此，适当的超声促进了 SPI-SI 相互作用，提高了复合物的稳定性和功能特性，为新复合物的开发及其在功能性食品中的应用提供了理论基础。
