Polyphenols Weaken Pea Protein Gel by Formation of Large Aggregates with Diminished Noncovalent Interactions

Abstract

Polyphenols are well-known native cross-linkers and gel strengthening agents for many animal proteins. However, their role in modifying plant protein gels remains unclear. In this study, multiple techniques were applied to unravel the influence of green tea polyphenols (GTP) on pea protein gels and the underlying mechanisms. We found that the elasticity and viscosity of pea protein gels decreased with increased GTP. The protein backbone became less rigid when GTP was present based on shortened T 1ρ H in relaxation solid-state NMR measurements. Electron microscopy and small-angle X-ray scattering showed that gels weakened by GTP possessed disrupted networks with the presence of large protein aggregates. Solvent extraction and molecular dynamic simulation revealed a reduction in hydrophobic interactions and hydrogen bonds among proteins in gels containing GTP. The current findings may be applicable to other plant proteins for greater control of gel structures in the presence of polyphenols, expanding their utilization in food and biomedical applications.

Adding Humic Acids to Gelatin Hydrogels: A Way to Tune Gelation

“…Thus, HAs improve elastic properties of the final gels if their concentration does not exceed 13.33 (wt/wt)% dry gelatin. In particular, this kind of interaction accounts for gel formation in the investigated samples, as evidenced by the marked dissolution of the gel in urea solution, which is effective in breaking hydrogen bonds . More specifically, FT-IR spectra and XRD patterns (Figures and a) clearly evidence that HAs affect gelatin structure.…”

“…In particular, this kind of interaction accounts for gel formation in the investigated samples, as evidenced by the marked dissolution of the gel in urea solution, which is effective in breaking hydrogen bonds. 44 More specifically, FT-IR spectra and XRD patterns (Figures 8 and 9a) clearly evidence that HAs affect gelatin structure. Notably, the addition of higher HA concentrations hinders the protein structuring into the triple helix conformation, probably because water molecules are constrained by interactions with HA moieties, preventing H-bonds between gelatin and water.…”

“…Samples for SEM analysis were prepared following the procedure reported elsewhere, 44 with some changes. Briefly, the samples were immersed in 1 mL pipet tips.…”

Functional, textural, and rheological properties of mixed casein micelle and pea protein isolate co-dispersions

“…We hypothesize that the concentration of protein in the blended system (4%) was too low to have a significant effect on viscosity (Bienvenue et al, 2003). For example, Chen et al (2021) observed that concentrated PP solutions (16%) showed shear thinning behavior rather than the Newtonian behavior of the 4% PP solution in this study.…”

Characterization and Cellular Uptake of Peptides Derived from In Vitro Digestion of Meat Analogues Produced by a Sustainable Extrusion Process

“…Small blocks of MA and CB were fixed using 2.5% (w/v) glutaraldehyde, washed with phosphate buffer, dehydrated using ethanol, cut to expose the fresh surface, critical-point-dried, sputtercoated, and imaged with a Quattro ESEM (Thermo Fisher Scientific, Waltham, MA, USA). 17 Three different blocks were imaged for each sample, and the representative results were shown.…”