Modulating protein-polysaccharide gel networks via almond protein to improve physicochemical stability of millet-based set yogurt.

Low soluble protein content and poor gelation in millet milk compromise the formation of firm set yogurts. This study developed a millet-based set yogurt with improved physicochemical stability by incorporating almond protein isolate (API; 0-2%, w/v), which contributes a mild flavor, acid stability, and gel-forming capacity. API supplementation promoted acid-induced gelation via ionic interactions within the protein-polysaccharide matrix. Formulations with 0.5-1% API formed self-supporting gels with higher firmness (1.46-7.31 N), higher water-holding capacity (97.92-99.00%), greater post-shear recovery, and lower deformation (p < 0.05). API supplementation elevated lactic acid bacteria counts in a concentration-dependent manner (5.29-7.00 log CFU/g; p < 0.05), with increased acid production and taste acceptability. However, 2% API caused excessive aggregation, pore collapse, syneresis, and structural heterogeneity. Accordingly, 1% API provided the best balance of stability, texture, and sensory acceptability, demonstrating the potential of this plant-derived protein for developing cereal-based yogurt alternatives.