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.