Development of novel plant protein with low gelation concentration from Torreya grandis nuts: Effect and mechanism of metal cations on its thermal gelation behavior

High protein concentrations were often required for thermally induced gelation, posing challenges in cost and resource efficiency. This study investigates the effects and mechanisms of metal cations (Na + , K + , Mg 2+ , Ca 2+ , 0–0.4 mol/L) on the thermal gelation behavior of Torreya grandis nut protein (TGNP) with a low gelation concentration (3 %–6 %). However, the addition of metal cations induced structural unfolding and an increase in particle size of TGNP from 358 to 3205 nm, leading to a decrease in TGNP solubility by an average of 8 %, which reduced TGNP gel properties, including modulus, hardness, and water-holding capacity. Furthermore, the presence of metal cations decreased the native β-sheet and disulfide bond content and increased the surface hydrophobicity of the TGNP gels, resulting in a loose structure and poorer stability. Overall, this study provides novel insights for the formulation and application of TGNP in edible delivery gels such as plant-based milk.