Viscoelastic properties of pressurised and heat-induced surimi gels made from Alaska pollock (Theragra chalcogramma) and Pacific whiting (Merluccius productus)

When Alaska pollock and Pacific whiting surimi gels induced by high hydrostatic pressures at 400 MPa or 650 MPa for 10 min at 22degreesC, or heat induced (90degreesC, 40 min) with added egg white and/or potato starch were tested for amplitude sweep, frequency sweep and creep/recovery, the additives did not affect the viscoelastic properties but pressure did. The lower the pressure the greater the elasticity of the gels. Phase angles (delta) for surimi gels were practically constant, indicating consistent solid-like behavior over the entire frequency range. The highest elasticity was exhibited in Alaska pollock surimi gels at 400 MPa with egg white (delta = 9.65degrees) and Pacific whiting surimi gels heat induced without additives (delta = 10.37degrees). The compliance data (J(0) (1/Pa)) of both pollock and whiting surimi gels exhibited the highest values in pressurised and heat-induced gels without additives. Pressure increased (P<0.05) elastic recovery response (over 85%) compared with heat-induced surimi gels (similar to76%).