In-vitro digestion assessment of DIAAR, protein digestibility, and ACE/COX inhibitory activity of solid-state fermented beans.

Adequate protein intake is critical during childhood to support growth, development, and immune function. This in vitro study evaluated the effect of solid-state fermentation with Pleurotus ostreatus on protein digestibility, amino acid profile, and bioactivity (ACE and COX inhibition) in two local bean varieties. Fermentation enhanced gastric-phase protein digestibility; however, only Roget beans showed a notable increase after intestinal stage (67% in fermented vs. 57% autoclaved samples, representing a 17.5% relative increase). Additionally, bioaccessible amino acid profile improved significantly in fermented Roget beans, with increases in hydrophobic and aromatic amino acids. Correspondingly, DIAAR values for lysine, valine, and isoleucine rose, while sulfur amino acids decreased, whereas Herradura beans showed limited or negative changes. Fermentation preserved COX-2 inhibition while reducing COX-1 activity. Overall, fermented Roget beans showed enhanced digestion and functional properties, suggesting nutritional benefits for consumers of local legume-based foods, particularly in child-oriented formulations, pending in vivo validation.