L-glutamic acid affects myosin aggregation and the physical properties of bighead carp (Aristichthys nobilis) surimi gels

The myosin aggregation of b.ighead carp ( Aristichthys nobilis ) induced by heating and the physical structure of surimi gels were changed using L-Glu. L-Glu increased the solubility of myosin regardless of heating or low/high ionic strength . Compared to myosin, the hydrophobicity of myosin with L-Glu at low ionic strength increased significantly, however there was no difference between myosin and myosin with L-Glu at high ionic strength. Atomic force microscopy and scanning electron microscopy results showed that L-Glu suppressed myosin aggregation, forming a honeycomb-like network after a two-step heating. Consequently, the suppression by L-Glu of myosin aggregation changed the physical properties of surimi gels. The water holding capacity of surimi gels with L-Glu increased significantly, but the hardness decreased. This study suggested that the influence of myosin aggregation induced using L-Glu increased ion-dipole interactions, hydrogen bonds and electrostatic repulsions, which changed the microstructure of surimi. L-Glu could be used as an additive to soften surimi gels with low salt for those with difficulty in chewing .