Effect of Coagulant Concentration on Soy Protein-Based Fiber for Meat Substitute by Wet Spinning Combined with Ionic Cross-Linking of Alginate

Meat substitutes production using plant-derived materials is attracting attentions as a solution for sustainable protein supply. We have previously reported the fabrication of soy protein-based fibers by combination of wet spinning and ionic cross-linking of alginate. In this study, we focused on the calcium ion concentration in the coagulant solution and alginate concentration in the spinning solution, which are determinant factors for in the gelation of alginate. The fiber diameter was reduced by increasing calcium ion concentration, probably due to the dehydration from fiber induced by osmotic pressure difference with coagulant solution and the suppression of swelling of fiber by the rapid gelation. The hardness of fibers evaluated by texture analysis increased as the concentrations of alginate and calcium ion increased, while the springiness increased with increasing calcium ion concentration but decreased with alginate concentration. The controlling the structure and texture of fibers by the compositions of spinning and coagulant solutions would improve their applicability to meat substitutes.