Improvement of gel properties of low salt surimi using low-dose l-arginine combined with oxidized caffeic acid

Abstract

The combined effects of l-arginine (Arg) and oxidized caffeic acid (OCF) treatment under different salt concentrations on gelling properties of bighead carp (Aristichthys nobilis) surimi gels were investigated. The results showed that the improvement of gel strength and water-holding capacity (WHC) of low-salt (0.5%) surimi gels could be obtained by adding Arg at various levels (0.1–0.4%) rather than OCF (0.1–0.9%, based on protein content). However, the gel strength and WHC of the low-salt surimi gel added with low-dose (0.1%) Arg alone were still far lower than that of regular-salt (3.0%) control. Whereas the significant improvements in low-salt surimi gels could be achieved when 0.1% Arg was combined with various levels of OCF, especially in combination with 0.5% OCF (LC-A-O). The water distribution in LC-A-O was markedly improved and its β-sheet structure content was significantly increased compared with the low-salt control (P < 0.05). Moreover, a denser and more uniform network structure of LC-A-O was obtained, which was probably due to much stronger and more intra-molecular cross-linking of proteins, via the formation of new adducts between OCF and surimi proteins. Hence, the combined treatment of Arg and OCF showed a potential for improving the gel properties of low-salt surimi.