Transglutaminase activity in pressure-induced gelation assisted by prior setting

Gels from horse mackerel (Trachurus trachurus) mince were induced by high pressure treatment at 300 MPa, 25 °C, 15 min. The effect of a prior setting at 25 °C, during 2 h at atmospheric pressure, on microstructural and rheological properties of gels was examined. Homogenates from minced muscle and ground salted paste in a saline medium containing 2-β-mercaptoethanol were prepared and subjected to high pressure treatment. Protein solubility, SDS-PAGE and TGase activity in the supernatants were determined. Residual TGase activity was significantly reduced after pressurization. Gels were found to be stronger and exhibited a denser and more homogeneous network when a prior setting preceded high pressure.