Synergistic regulation of porcine plasma gel properties by thrombin and transglutaminase

This study systematically examined the synergistic modulation of porcine plasma gels using thrombin and transglutaminase (TGase). The gelation process, mechanical properties, and structural evolution were characterized through texture profile analysis, rheometry, scanning electron microscopy, Fourier-transform infrared spectroscopy, and intrinsic fluorescence spectroscopy. The results demonstrated that thrombin significantly shortened gelation time and enhanced elastic modulus, while TGase notably improved gel strength, water-holding capacity, and promoted the formation of a finer, more homogeneous microstructure. Structural analysis indicated that both enzymes facilitated a conformational transition from α-helix to β-sheet, strengthened hydrogen bonding and hydrophobic interactions, and increased cross-linking density. Notably, the dual-enzyme system effectively combined the rapid-gelling advantage of thrombin with the strengthening effect of TGase, yielding gels with accelerated formation and superior mechanical performance. Thrombin established the primary fibrin network, while TGase introduced covalent cross-links within this structure. These findings revealed the complementary mechanisms of thrombin and TGase in regulating protein network assembly,and provided practical approach to designing 3D-printable gels and specialized food formulations.