Improving the texture and rheological qualities of a plant-based fishball analogue by using konjac glucomannan to enhance crosslinks with soy protein

Global fisheries pressure generates interest in sustainable seafood production and developing plant-based seafood. This study took fishball as an example of seafood products applying konjac glucomannan (KGM) in developing plant-based fishball (PFB) analogues mimicking the texture of fishball. Increasing KGM concentration (up to 8.0%) influenced texture and rheological properties of PFB progressively, where the hardness, chewiness, and gel strength of PFB were significantly enhanced. Decreased pH value (9.38 to 7.93) and increased α-helix, β-sheet, and helix/coil ratio (1.40 to 1.70%) validated a promotion of hydrogen bonds and ordered structures by KGM. The strengthened interaction strength and hydrogen bonds formed at -OH groups of KGM and amide linkage of soy protein could be responsible for textural improvement. A more compact and regular microstructure also validated a firmer texture in PFB with higher KGM levels. Besides, KGM (3.5–8.0%) significantly decreased instantaneous compliance J0 (101.3 × 10−6 to 58.1 × 10−6 Pa−1), indicating denser crosslinks and firmer structures. In conclusion, KGM improved the texture and viscoelasticity of PFB and had an excellent application value in developing plant-based seafood analogues.