Construction and characterization of binary hydrogels based on pea protein isolate and konjac glucomannan.

BACKGROUND: Hydrocolloids such as konjac glucomannan (KGM) and pea protein isolate (PPI) play a central role in food gel structuring by modulating texture and water retention. This study systematically investigated the gelation behavior, structural evolution, and interaction mechanism of PPI/KGM composite hydrogels prepared with different formulation compositions. RESULTS: Pure KGM (15 g L-1) formed weak and soft gels, whereas pure PPI (100 and 125 g L-1) produced brittle gels accompanied by syneresis. Compared with the individual components, the binary hydrogels exhibited higher storage moduli, reduced syneresis, and more compact interconnected network structures. Low-field nuclear magnetic resonance analyses revealed the emergence of an immobile water population together with a redistribution of water within the gel network. Fourier transform infrared analysis showed strengthened hydrogen bonding between PPI and KGM, accompanied by decreases in α-helix and β-sheet contents and an increase in β-turn content, indicating protein conformational rearrangement. Cryo-scanning electron microscopy further confirmed the formation of dense and interconnected gel networks, providing structural evidence for the enhanced viscoelasticity and improved water retention of the binary hydrogels. CONCLUSION: Overall, PPI/KGM binary hydrogels offer tunable structural and hydration properties without the need for chemical or enzymatic crosslinking, providing a sustainable platform for high-moisture foods, dairy alternatives, and meat analogs. © 2026 Society of Chemical Industry.