Effect of salt on solution behavior of spinning medium and properties of meat analogue fibers

Wet-spinning receives increasing interest as a potential method for mimicking natural animal muscle fibers. Here we systematically studied the effect of type and content of salt ions on the behavior of spinning solution composed of sodium alginate (SA) and soybean protein isolate (SPI), as well as the properties of meat analogue fibers. The properties of the composite spinning solution are first determined by adding salt ions, allowing for control over rheological chacracteristics. After wet-spinning, the SEM images illustrated higher salt content resulting in a more porous structure. FTIR proved the salt changed the secondary structure of the protein of the SA/SPI composite fibers. More importantly, increasing salt content could improve the juiciness of the meat analogue fibers by enhancing the water holding capacity and changing the moisture distribution. Generally, our work not only enriched the details of preparing meat analogue fibers based on plant proteins and polysaccharides by the wet-spinning method but also provided a theoretical reference for their industrial production.