SPUN PROTEIN FIBERS - EFFECT OF COMPOSITION OF THE SPINNING DOPE ON TEXTURE

Protein dopes were prepared with soybean protein in combination with alkali and salt at various concentrations and were spun into fibers by extrusion through a spinneret into an acid coagulation bath. The viscosity of the dope increased with increases in protein and NaOH concentrations. The presence of NaCl increased viscosity at low concentrations, but larger concentrations (> 0.1 M/kg) caused a decrease. The texture characteristics of spun protein fibers appeared to be related to the concentration of alkali and the presence of NaCl in the protein dope. This effect is interpreted as being due to electrostatic repulsion, molecular unfolding in the dope and molecular interactions when coagulation takes place in the fiber.