2013 Volume 19 Issue 1 Pages 117-122
The role of superoxide anion radical (O2−) in the improvement of bread dough by L-ascorbic acid (AsA) was examined. Since AsA makes detection of thiyl radicals (S•) difficult, riboflavin was used as a photoinduced O2− producing agent in substitution of the classical improvement molecule. The preparation of soluble glutenin was successfully achieved by means of deamidation using protein glutaminase. Electron spin resonance (ESR) spectroscopy coupled with spin trapping revealed the presence of photoinduced S• in a solution containing riboflavin and soluble glutenin. Unlike catalase, addition of superoxide dismutase suppressed the production of S• in the soluble glutenin. These results suggest that the O2− produced during the oxidation of AsA in dough is responsible for the generation of S• in gluten proteins, thereby increasing the production of inter-protein disulfide bonds and resulting in an improved bread structure.
