Soybean Trypsin Inhibitors (STIs) in soy-based foods have negative effects on soybean protein digestion and pancreatic health of humans. The inactivation of STIs is a critical unit operation aimed at enhancing the nutritional properties of soy-based foods during processing. This paper reviews the structure of STIs and soybean proteins, as well as the mechanisms of digestion. Various technologies (physical, chemical, biological) have been used to inactivate STIs. Their parameter settings, operating procedures, advantages, and disadvantages are also described. Mechanisms of inactivation of STIs (Kunitz trypsin inhibitor (KTI) and Bowman–Birk inhibitor (BBI)) conformations under different treatments are clarified. In addition, emerging technologies, e.g., Ohmic Heating, Electron Beam Irradiation, Dielectric-Barrier Discharge, and probiotics, have demonstrated great potential to inactivate STIs. We advise that multiple emerging technologies should combine with other unit operating systems to maximize inactivation efficiency.
This study investigated the physicochemical properties of gels induced by heat treatment in the presence of 10% polymerized whey protein (PWP) and different concentrations (1-4%) of Astragalus polysaccharide (AGPS). The results of the particle size, zeta potential, surface hydrophobicity, intrinsic fluorescence, surface free sulfhydryl, rheological and differential scanning calorimetry showed that AGPS improved the tertiary structure stability of PWP. Simultaneous rheology and Fourier transform infrared spectroscopy (SR-IR) traced the breaks of aromatic groups and the formation of PWP-AGPS hydrogels through hydrogen bonding and electrostatic interactions during heat process. The correctness of the experimental results was verified via molecular docking and 2-dimensional correlation spectroscopy (2D-COS). Cryogenic scanning electron microscopy images showed that the interaction between PWP and AGPS caused the denser microstructure of hydrogels. In summary, AGPS could promote gelation and improve the physicochemical properties of PWP-AGPS hydrogels. The findings of this study provided a theoretical basis for the application of protein-polysaccharide hydrogels in the food industry, offering insights for practical use.
17 April 2025 in International Journal of Biological Macromolecules