Effects of Konjac Glucomannan on Functional and Structural Properties of Antarctic Krill Surimi Gel

Antarctic krill surimi is a novel type of gel-based food that has attracted increasing attention. However, pure Antarctic krill surimi generally exhibits poor gel-forming properties. Konjac glucomannan (KGM) offers a promising approach to address this limitation due to its gel-forming ability and thermal stability. This study investigated the effect of KGM (0.0-20.0 mg/g) on the functional properties and structural characteristics of Antarctic krill-KGM surimi gels. The results demonstrated that as KGM levels increased, water-holding capacity, whiteness, hardness, chewiness, and gel strength of the composite surimi gels first increased and then decreased, while cooking loss followed the opposite trend. Texture analysis showed that gel strength was significantly enhanced at 10.0 mg/g KGM, reaching a maximum value of 1581.78 ± 12.86 (<i>p</i> < 0.05). Water distribution analysis confirmed that the relative content of immobilized water increased with increasing KGM levels. Fourier transform infrared spectroscopy demonstrated that the Antarctic krill-KGM surimi gels were primarily linked by non-covalent intermolecular interactions. Furthermore, microstructural analysis showed that KGM contributed to a more homogeneous and continuous gel matrix. These results indicate that KGM can modulate electrostatic repulsion, spatial potential resistance, and act as a reinforcing filler in the surimi gel matrix. Overall, the results demonstrated that KGM is a feasible candidate for enhancing the quality of Antarctic krill surimi gels.