Influence of L-arginine addition on the gel properties of reduced-salt white leg shrimp (Litopenaeus vannamei) surimi gel treated with microbial transglutaminase

This study aimed to investigate the effects of l-arginine (L-Arg) on the gel properties of reduced-salt shrimp surimi gel (SSG) treated with microbial transglutaminase (MTGase). The results showed that replacing NaCl with different concentrations of L-Arg in reduced-salt (0.5% NaCl) shrimp surimi treated with MTGase significantly increased the gel strength and texture of SSG, even at low L-Arg (0.5%) concentrations. However, 0.5% L-Arg added alone under low-salt conditions did not significantly improve the gel strength of SGG compared with the control SSG containing 0.5% NaCl. L-Arg and MTGase added together significantly increased the disulfide bonds and protein β-sheet structure of SSG while improving the moisture distribution and rheological properties. The electrophoretic analysis and microstructure images revealed that L-Arg and MTGase together promoted the cross-linking of proteins in shrimp surimi to form a dense gel network structure. In conclusion, the combined treatment of L-Arg and MTGase significantly improved the gel properties of SSG and reduced the amount of NaCl. Therefore, the combined treatment of L-Arg and MTGase could enhance the quality of reduced-salt shrimp surimi products.