Chicken plasma protein affects gelation of surimi from bigeye snapper (Priacanthus tayenus)

Effect of chicken plasma protein (CPP) at different concentrations on gel properties of grade SA and A bigeye snapper surimi was investigated. Addition of 0.5% CPP in combination with setting at 40 °C for 30 min prior to heating at 90 °C for 20 min resulted in the highest breaking force and deformation (P<0.05). However, whiteness decreased to some extent. CPP was able to prevent the degradation of surimi proteins as indicated by the decrease in TCA-soluble peptides (P<0.05). Electrophoretic studies revealed that myosin heavy chain underwent polymerization to a lower extent as CPP concentration increased. Therefore, CPP worked as protease inhibitor rather than protein cross-linker. Microstructure of kamaboko gels, added with 0.5% CPP, had less linkage between protein strands with a coarser fibrillar structure, indicating the interfering effect of CPP on cross-linking of myofibrillar proteins. Thus, at an appropriate amount, CPP possibly worked as a filler in the surimi gel matrix, resulting in gel strengthening.