Effect of high-pressure treatments prior to cooking on gelling properties of unwashed protein from barramundi (Lates calcarifer) minced muscle

Heat-induced gelling properties of barramundi minced muscle with 1.5% and 2% added salt were assessed after application of pressures at 300, 400 and 500MPa at 4 degrees C (initial temperature) for 10min and subsequent cooking at 90 degrees C for 30 min. Whiteness, gel-forming ability, water-holding capacity, hardness and springiness of the barramundi gels increased as applied pressure and salt concentration increased. At 2% salt concentration, high-pressure treatment results in barramundi gels with higher gel strength, mechanical properties and smoother texture as compared to conventional heat-induced gels (0.1MPa, 90 degrees C for 30). At a reduced salt concentration (1.5%) and pressure400MPa, the quality (gel strength, water-holding capacity, hardness and springiness) of pressurised cooked gels is comparable to those heat-induced gels with 2% added salt, but the microstructure is smoother. Scanning electron microscope images of pressurised cooked gels showed dense and compact network with smoother surface than those of heat-only-induced gels. Thus, application of high-pressure treatment prior to cooking could be an effective method to enable reduced salt concentration in barramundi gels.