Comparative Evaluation of Plant Protein Isolate Blends and Commercial Isolates: Structural, Digestive, and Functional Insights

Three plant protein isolate (PlPI) blends were formulated using mung bean, chickpea, sesame, peanut, and spirulina, and compared with seven commercial plant protein isolates (CPlPIs) to evaluate nutritional, structural, digestive, and functional properties. PlPI blends showed superior essential amino acid content, higher soluble protein, and in vitro protein digestibility (73–82%) compared to CPlPIs (33–64%). The improved digestibility was linked to a higher α-helix/β-sheet ratio (24.1%), as confirmed by FTIR, and favorable microstructures observed via SEM and TEM. SDS-PAGE revealed greater levels of β-conglycinin and glycinin in PlPI blends, contributing to improved emulsion stability. Overall, PlPI blends demonstrated enhanced solubility, digestibility, and emulsifying capacity due to synergistic effects of individual proteins. These results highlight PlPI blends as promising, sustainable alternatives for inclusion in protein-rich functional foods and beverages.