Development and characterization of polysaccharide–protein composite gels for dysphagia-friendly applications
摘要
Developing dysphagia-oriented foods requires texture-modified gel matrices with adequate structural integrity and stable viscoelastic properties, whereas single-thickener systems often provide limited control over overall gel performance. Here, we developed and characterized a fermented polysaccharide–protein composite gel system based on high-acyl gellan gum (HA-GG) and hydroxypropyl methylcellulose (HPMC). Candidate food-grade polysaccharides permitted under GB 2760-2014 were first screened, followed by single-factor experiments and a three-factor, four-level L16 (4³) orthogonal design to optimize formulation composition and fermentation time. Among twelve candidates, only HA-GG and HPMC satisfied all screening criteria. The optimal condition was 0.3 wt% HPMC, 0.3 wt% HA-GG, and 13 h fermentation, and all three factors significantly affected screening performance. Under the optimized condition, gel hardness increased at moderate polysaccharide incorporation but declined at higher levels. Rheological analysis confirmed elastic-dominant gel behavior across formulations, while scanning electron microscopy revealed improved network continuity at moderate incorporation but excessive compactness at higher levels. These findings demonstrate that balanced polysaccharide–protein network organization is critical for the rational design of stable fermented gel matrices with potential relevance to dysphagia-oriented food applications.