Fermentation-induced modifications to the structural, surface, and functional properties of quinoa proteins.

This research study investigates the relationship between the structural characteristics, water solubility, and protein digestibility of quinoa proteins (QPs) during fermentation. The fermentation process induces structural modifications in QPs, thereby enhancing their surface properties and functional attributes. Using advanced analytical techniques, such as ultraviolet, fluorescence, and FT-IR spectra, it has been demonstrated that fermented QPs exhibit significant structural changes (P < 0.05) compared to unfermented QPs. Notably, fermentation significantly increases the digestibility of QPs from 78.13 to 85.24%, thereby enhancing their nutritional value. Furthermore, surface properties undergo modifications, with a decrease in surface charge from -32.82 to -39.63 and a reduction in surface hydrophobicity from 580 to 382 a.u. These findings underscore the transformative impact of fermentation on QPs, resulting in improved digestibility, modifications in protein structure, and enhanced nutritional benefits. Further research on water kefir-based fermentation is needed to optimize its quality.