TY - JOUR

T1 - Heat-induced gels from pea protein soluble colloidal aggregates

T2 - Effect of calcium addition or pH adjustment on gelation behavior and rheological properties

AU - Ren, Wenbo

AU - Xia, Wenjie

AU - Gunes, Deniz Z.

AU - Ahrné, Lilia

N1 - Funding Information: The authors would like to thank the Platform for gentle processing at University of Copenhagen and China Scholarship Council for financial support (CSC No. 202003250075 ). Publisher Copyright: © 2023 The Authors

PY - 2024

Y1 - 2024

N2 - Heat-induced protein gels are appreciated due to their texture in a variety of food products. To support the shift to more sustainable protein consumption more knowledge is needed about plant protein gelation behavior and rheological properties of gels. In this study, the effect of calcium concentration (10 mM–100 mM) and pH (5.9–6.8) on heat-induced gelation behavior of 10 w/w% pea protein water-soluble extract separated from a commercial pea protein isolate (WSE-PPI) were for the first time investigated and compared. The rheological results show Gʹ values of around 3000 Pa for gels containing 20 mM calcium, and then a decrease in Gʹ by a factor ∼1.3 when the calcium concentration increased to 100 mM, whereas a continuous increase in gel strength was observed with the pH decrease of WSE-PPI dispersions. By comparison of calcium-addition and pH-adjusted heat-induced gels at the same pH, it was found that at low calcium concentrations (≤20 mM), the calcium-assisted gels exhibited higher gel strength. Contrariwise, at high calcium concentrations (≥50 mM), the pH-adjusted gels have higher gel stiffness and larger deformability before rupture. CLSM results verified this finding and show that the gel structure of pH-adjusted gels are more homogenous, containing significantly more compact structure. Overall, our findings show a systematic link between microstructure and rheological properties of heat-induced gels, which can be controlled by the calcium addition and pH adjustment. These results provide valuable information for the modulation, design, and customization of plant derived protein gels for specific food applications.

AB - Heat-induced protein gels are appreciated due to their texture in a variety of food products. To support the shift to more sustainable protein consumption more knowledge is needed about plant protein gelation behavior and rheological properties of gels. In this study, the effect of calcium concentration (10 mM–100 mM) and pH (5.9–6.8) on heat-induced gelation behavior of 10 w/w% pea protein water-soluble extract separated from a commercial pea protein isolate (WSE-PPI) were for the first time investigated and compared. The rheological results show Gʹ values of around 3000 Pa for gels containing 20 mM calcium, and then a decrease in Gʹ by a factor ∼1.3 when the calcium concentration increased to 100 mM, whereas a continuous increase in gel strength was observed with the pH decrease of WSE-PPI dispersions. By comparison of calcium-addition and pH-adjusted heat-induced gels at the same pH, it was found that at low calcium concentrations (≤20 mM), the calcium-assisted gels exhibited higher gel strength. Contrariwise, at high calcium concentrations (≥50 mM), the pH-adjusted gels have higher gel stiffness and larger deformability before rupture. CLSM results verified this finding and show that the gel structure of pH-adjusted gels are more homogenous, containing significantly more compact structure. Overall, our findings show a systematic link between microstructure and rheological properties of heat-induced gels, which can be controlled by the calcium addition and pH adjustment. These results provide valuable information for the modulation, design, and customization of plant derived protein gels for specific food applications.

U2 - 10.1016/j.foodhyd.2023.109417

DO - 10.1016/j.foodhyd.2023.109417

M3 - Journal article

AN - SCOPUS:85174189534

VL - 147

JO - Food Hydrocolloids

JF - Food Hydrocolloids

SN - 0268-005X

M1 - 109417

ER -