Cereal Chem. 71:311- 314   |  VIEW ARTICLE


Methoxyhydroquinone in Wheat Flour.

B. K. Koh and R. C. Hoseney. Copyright 1994 by the American Association of Cereal Chemists, Inc. 

Wheat flour dough, when mixed beyond its optimum mixing time, shows a rapid breakdown. This phenomenon is believed to be caused by something in the water-soluble fraction of flour becoming oxidized to form an activated double-bond compound that reacts with gluten. Methoxyhydroquinone (MHQ) and related compounds were studied in relation to this rapid dough breakdown. The mixograph was used to determine their physical effects on dough mixing performance. MHQ accelerated dough breakdown when the dough was mixed in air. It was more effective than other activated double-bond compounds. No free MHQ was found in the flour. MHQ was released by acid or beta-glucosidase hydrolysis of the water-soluble fraction of flour. The amount of MHQ was determined by high-performance liquid chromatography equipped with a fluorescence detector. MHQ endogenous in flour and bound by a beta-glycosidic linkage was not effective in accelerating dough breakdown, presumably because it does not become oxidized as easily as the free hydroquinone.