Influence of gelatin modification on kidney bean protein hydrogels formation: Molecular structure, thermal aggregation and network.

With the increasing awareness of sustainability and physical health, plant protein gels, as alternatives to animal protein gels, have become a research hotspot in the development of new healthy foods. Studies on plant proteins as substitutes for animal proteins have mainly focused on their gel properties, these properties remain inferior to those of animal proteins. Consequently, modulating and enhancing the gel properties of plant proteins constitute a key challenge and research priority. Here, this study explores the influence of gelatin (Gel) modification on the thermal gel behavior of kidney bean protein. When the Gel concentration of 2% (w/v), a denser cross-linked network was formed in kidney bean protein through heat-induced gelation at 90 °C. Additionally, the grafting of kidney bean protein with Gel causes the helical structure to transition to a more stable β-sheet structure (43.97 ± 3.49%). Heat-induced hydrogel K10/G2 exhibited enhanced surface hydrophobicity (68.95 ± 1.91), promoting the formation of intermolecular disulfide bonds between kidney bean protein and Gel. By modifying kidney bean protein with Gel, more 11S acidic peptides and 7S β subunits appeared in heat-induced hydrogel K10/G2. This study provides a strategy for preparing kidney bean protein with a stable cross-linked network structure, which offers fundamental insights that support its potential use in clinical nutrition and specialized medical food formulations.