Hao Junyu, Zhang Zhuchi, Yang Ming, Zhang Yongli, Wu Tao, Liu Rui, Sui Wenjie, Zhang Min
Sate Key Laboratory of Food Nutrition and Safety, Food Biotechnology Engineering Research Center of Ministry of Education, Tianjin University of Science & Technology, Tianjin, 300457, China.
Tianjin Agricultural University, Tianjin, 300384, China.
Bioresour Bioprocess. 2022 Jul 25;9(1):77. doi: 10.1186/s40643-022-00565-9.
The present study aimed to investigate the functional properties of soybean protein isolate (SPI) treated with alkaline protease and high-speed shearing homogenization. Alkaline protease-hydrolyzed SPIs that were characterized by varying degrees of hydrolysis between 0 and 6% were treated with high-speed shearing homogenization to obtain different micro-particulate proteins. The results showed that this combined treatment could significantly reduce the particle size of SPI by markedly degrading the structure of both the 7S and 11S subunits, thereby resulting in a significantly reduced content of β-sheet and β-turn structures. The surface hydrophobicity increased considerably for samples with hydrolysis below the threshold of 2% and then declined gradually above this threshold. Furthermore, the combination of hydrolysis and homogenization significantly improved the emulsion stability of SPI hydrolysates. It also significantly improved the foaming properties of SPI. These results demonstrated that alkaline protease hydrolysis combined with high-speed shearing homogenization represents a promising approach for improving the functional and structural properties of SPI.
本研究旨在探究经碱性蛋白酶处理和高速剪切均质化处理的大豆分离蛋白（SPI）的功能特性。对水解度在0%至6%之间变化的碱性蛋白酶水解SPI进行高速剪切均质化处理，以获得不同的微颗粒蛋白。结果表明，这种联合处理可通过显著降解7S和11S亚基的结构，从而显著降低SPI的粒径，进而导致β-折叠和β-转角结构的含量显著降低。水解度低于2%阈值的样品表面疏水性显著增加，然后在该阈值以上逐渐下降。此外，水解和均质化的组合显著提高了SPI水解产物的乳化稳定性。它还显著改善了SPI的发泡性能。这些结果表明，碱性蛋白酶水解与高速剪切均质化相结合是改善SPI功能和结构特性的一种有前景的方法。
