Gelling Properties of Spanish Mackerel (Scomberomorus niphonius) Surimi as Affected by Washing Process and High Pressure

This study evaluated the effect of washing conditions on gel properties of Spanish mackerel and investigated the application of high pressure to improve the gel properties of Spanish mackerel. Alkaline-saline washing process surimi (ASWPS) showed the increase in gel strength by 40.19% than unwashed surimi, and by 26.74% than conventional washing process surimi (CWPS). These increases were associated with the lowered expressible moisture content. However, no differences were found in deformation of gels prepared by different washing processes. Electrophoretic studies revealed that ASWPS had the highest MHC and actin band intensity. Alkaline-saline washing process surimi was subjected to ultra-high pressures of 100, 200, 300, 400, 500 MPa for 30 min at 40 degrees C. The effects of pressure on both springiness and cohesiveness were insignificant. Hardness and chewiness of samples treated at 300 and 400 MPa increased significantly when compared with the control, which increase by 2.68 and 2.40 times at 300 MPa and by 2.87 and 2.70 times at 400 MPa, respectively. However, these values slightly decreased after treatment at 500 MPa. In addition, pressure increased the whiteness of surimi, the higher pressure the more increase.