Molecular basis of sodium chloride dominated glutenin interaction and bread properties

Dough elasticity and bread quality depend on the gluten network formation which by nature is the oxidative crosslinking of glutenin. It is known for long, either in the kitchen or in the laboratory, sodium chloride (NaCl) enhances dough rheological properties while itself is not an oxidant. However, besides NaCl induced gluten aggregation, the molecular mechanism behind this phenomenon is largely unknown. Azodicarbonamide (ADA) and Vitamin C (Vc) improve dough qualities with different mechanisms. Here, response surface methodology (RSM) was used to study the synergistic effect of ADA, Vc and NaCl on the dough and subsequent bread qualities. Results show that NaCl dominates the dough alveographic characters in the presence of oxidative flour improvers, and fine tune of NaCl concentration profoundly impacts subsequent bread properties. Consistent with free sulfhydryl assay and glutenin gel electrophoresis analysis, simulation study reveals that NaCl concentration affects glutenin conformation and intermolecular interaction which in turn impacts their orientation adjustment that lead to sulfhydryl contact and crosslinking.