Molecular Oxygen and Reactive Oxygen Species in Bread-making Processes: Scarce, but Nevertheless Important.

In bread making, O2 is consumed by flour constituents, yeast, and, optionally, some additives optimizing dough processing and/or product quality. It plays a major role especially in the oxidation/reduction phenomena in dough, impacting gluten network structure. The O2 level is about 7.

Impact of pyranose oxidase from Trametes multicolor, glucose oxidase from Aspergillus niger and hydrogen peroxide on protein agglomeration in wheat flour gluten-starch separation.

The impact of pyranose oxidase (P₂O), glucose oxidase (GO) and H₂O₂ on gluten agglomeration during wheat flour gluten-starch separation was studied. Analysis of gluten aggregate sizes in batter formed from wheat flour dough revealed that increasing levels of oxidising agents gradually decreased the tendency of gluten proteins to form large gluten aggregates. Low enzyme levels increased arabinoxylan (AX) and starch retention on the sieves, due to physical incorporation of AX and starch in the gluten aggregates.

The bread dough stability improving effect of pyranose oxidase from trametes multicolor and glucose oxidase from Aspergillus niger: unraveling the molecular mechanism.

Glucose oxidase (GO) and pyranose oxidase (P2O) improve dough stability and bread quality. We here studied whether their mode of action resides in cross-linking of proteins and/or arabinoxylan (AX) molecules through the production of H2O2. Evidence for both was deduced from a decrease in extractability of protein and AX from dough made with P2O, GO, or H2O2, using sodium dodecyl sulfate containing buffer and water, respectively.