Role of gellan gum in multiscale assembly and structure-property relationships of potato protein-soybean protein fibril-pea protein fibril composite gels.

Multicomponent gels integrating globular plant proteins with protein fibrils offer a promising soft-matter route for texture design in plant-based meat analogues (PBMAs), yet the polysaccharide-mediated multiscale assembly underlying their structure-property relationships remains poorly understood. In this study, gellan gum (0-4.0 wt%) was used to modulate composite gels comprising potato protein, soybean protein fibrils, and pea protein fibrils (2:1:1, w/w/w). Gellan gum modulated the pre-assembly state, as indicated by changes in apparent soluble-protein fraction, ζ-potential, ANS-derived surface hydrophobicity, and DTNB-reactive -SH content, while gel strength and water holding capacity showed concentration-dependent responses among the self-supporting formulations, with the highest mean values observed at 3.0 wt% gellan gum. Quantitative SEM (500×) revealed concurrent pore refinement, reaching the lowest apparent porosity (50.55%) and apparent D50 (4.61 μm) at 2.0 wt% gellan gum, whereas 4.0 wt% gellan gum partially reintroduced larger pores (apparent D50, 5.71 μm). A concentration-adjusted Mantel analysis was used to separate concentration-driven co-variation from robust links between interactions, thermo-rheology and pore architecture. These results reveal a concentration-dependent trade-off between pore refinement, structural uniformity, and mechanical rigidity, offering a mechanistic basis for soft-matter structuring of PBMAs.