Cereal Chem 69:266-270   |  VIEW ARTICLE

Reduction of Phytic Acid During Breadmaking of Whole-Meal Breads.

B. Fretzdorff and J.- M. Brummer. Copyright 1992 by the American Association of Cereal Chemists, Inc. 

Reduction of phytate was studied in model dough systems using whole-grain coarse meals or flours and during breadmaking of coarse meal breads from wheat and rye. It was found that pH was the most important factor in reducing phytic acid content. In doughs with pHs of 4.3-4.6, adjusted with citric or lactic acid, phytic acid content was more effectively reduced than in doughs with higher pHs. Phytic acid was almost completely hydrolyzed in doughs made from whole-grain flours at pH 4.5 and 30 C after a 4-hr incubation. Reductions of phytic acid content in doughs made from coarse meals were small, but with increasing temperature (up to 55 C) phytic acid concentrations were less than 8 and 4% of original concentrations for wheat and rye, respectively. Further increase of the temperature (above 55 C) of the unfermented sponge resulted in smaller reductions of phytic acid. In acidified unfermented sponges (pH 4.4-4.6), the residual phytic acid was less than 10% of original concentrations. From dough mixing through baking, the content of phytic acid was reduced to about 20 and 33% for wheat and rye, respectively. Phytic acid contents ranged from 6.3 to 10.1 mg/g (dry matter) and from 0.6 to 2.7 mg/g (dry matter) for wheat and rye meal breads, respectively.