Temperature dependence of relaxation spectra for highly hydrated gluten networks

In the present investigation, the temperature dependence (0e50 �C) of the relaxation spectrum of
hydrated gluten was studied using novel numerical algorithms. Tikhonov regularization, in conjunction
with the L-curve criterion for optimal calculation of the regularization parameter, was used to generate
the relaxation spectrum from stress relaxation measurements on shear. The methodology used revealed
six molecular events with baseline resolution that could be grouped into fast- and slow-relaxation
regimes. The fast-relaxation regime exhibited strong temperature dependence whereas the slow one is
temperature independent indicating on the whole two dominant mechanisms of interactions. The “loop
and train” structural model for gluten interactions was found adequate to describe the relaxation events
in this system, with the fast regime being assigned to interactions due to hydrogen bonding whereas the
slow one to permanent cross-linking of the entire network. Findings of the present investigation provide
fundamental understanding and give new insights into the complexity of interactions and relaxation
modes of hydrated gluten.