Wang Zihuan, Gong Shaoying, Wang Yucong, Liu Danyi, Han Jianchun
College of Food Science, Northeast Agricultural University, Harbin 150030, China.
Heilongjiang Green Food Science Research Institute, Harbin 150030, China.
Foods. 2021 Nov 17;10(11):2829. doi: 10.3390/foods10112829.
Soybean protein isolate (SPI) is a kind of plant derived protein with high nutritional value, but it is underutilized due to its structural limitations and poor functionalities. This study aimed to investigate the effects of high hydrostatic pressure (HHP) treatment on SPI and sodium alginate (SA) conjugates prepared through the Maillard reaction. The physicochemical properties of the conjugate synthesized under 200 MPa at 60 °C for 24 h (SPI-SA-200) were compared with those of the conjugate synthesized under atmospheric pressure (SPI-SA-0.1), SPI-SA mixture, and SPI. The HHP (200 MPa) significantly hindered the Maillard reaction. This effect was confirmed by performing SDS-PAGE. The alterations in the secondary structures, such as α-helices, were analyzed using circular dichroism spectroscopy and the fluorescence intensity was determined. Emulsifying activity and stability indices of SPI-SA-200 increased by 33.56% and 31.96% respectively in comparison with the SPI-SA-0.1 conjugate. Furthermore, reduced particle sizes (356.18 nm), enhanced zeta potential (‒40.95 mV), and homogeneous droplet sizes were observed for the SPI-SA-200 emulsion. The present study details a practical method to prepare desirable emulsifiers for food processing by controlling the Maillard reaction and improving the functionality of SPI.
大豆分离蛋白（SPI）是一种具有高营养价值的植物源蛋白，但由于其结构限制和功能不佳而未得到充分利用。本研究旨在探讨高静水压（HHP）处理对通过美拉德反应制备的SPI与海藻酸钠（SA）共轭物的影响。将在60℃、200MPa下反应24小时合成的共轭物（SPI-SA-200）的理化性质与在常压下合成的共轭物（SPI-SA-0.1）、SPI-SA混合物和SPI的理化性质进行比较。HHP（200MPa）显著阻碍了美拉德反应。通过进行SDS-PAGE证实了这种效果。使用圆二色光谱分析二级结构的变化，如α-螺旋，并测定荧光强度。与SPI-SA-0.1共轭物相比，SPI-SA-200的乳化活性和稳定性指数分别提高了33.56%和31.96%。此外，SPI-SA-200乳液的粒径减小（356.18nm），ζ电位增强（-40.95mV），且液滴尺寸均匀。本研究详细介绍了一种通过控制美拉德反应和改善SPI功能来制备用于食品加工的理想乳化剂的实用方法。
