Optimizing the rheological and structural synergism of alginate and welan gum as blended biocomposites

BACKGROUND: Welan gum (WL) is costly and chemically inert, limiting its applications. Blending with sodium alginate (SA) overcomes this by synergistic interactions that enhance viscosity and rheological properties, forming a promising composite hydrocolloid gel. RESULTS: The viscoelastic properties for nonlinear behavior under large deformation and the effect of environmental factors on the zero-shear viscosity of the SA-WL mixtures have been investigated. The physical properties of the SA-WL mixtures at different concentrations and ratios were studied systematically by analyzing the effects of the shear rate, strain, frequency, and temperature. The synergistic effect was strongest at 1% total concentration with an SA:WL ratio of 2:8, where the storage modulus (G') exceeded the loss modulus (G″), indicating elastic-dominant behavior. The results showed that the zero-shear viscosity of the SA-WL (2:8) mixture reached a maximum of 1464.51 ± 146.332 Pa s, compared to 0.134 ± 0.021 and 870.513 ± 23.514 Pa s for pure SA and WL, respectively. CONCLUSION: A higher content of WL than SA in the blends led to a more compact and elastic composition, shown by higher values of G' than G″. This synergistic interaction offers promising applications in food products requiring enhanced viscosity, stability, and texture modulation, including sauces, dressings, and dysphagia food. © 2026 Society of Chemical Industry.