posted on 2021-01-26, 09:03authored byDa Chen, Xiao Zhu, Jan Ilavsky, Tanya Whitmer, Emmanuel Hatzakis, Owen G. Jones, Osvaldo H. Campanella
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 T1ρH 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.