Effect of wheat bran and enzyme addition on dough functional performance and phytic acid levels in bread

Effects of bran concentration, bran particle size distribution, and enzyme addition - fungal phytase, fungal alpha-amylase - on the mixing and fermentative behaviour of wheat dough and on the amount of phytic acid remaining in bread have been investigated using a factorial design of samples 2(4). Bran concentration and bran particle size significantly affected all Farinograph parameters, whereas enzyme effects were particularly observed on both the water absorption of the flour and the parameters characterizing the overmixing. Water absorption was maximized in doughs with higher fine bran addition and/or in Boughs with no enzymes, and was minimized in blends containing coarse added bran and alpha-amylase and/or alpha-amylase and phytase. alpha-Amylase addition had a significant positive effect on dough development and gassing power parameters during proofing. At low bran addition, phytate hydrolysis takes place to a greater extent than at high bran addition levels. Combination of bran with amylolytic and phytate-degrading enzymes could be advisable for overcoming the detrimental effect of bran on the mineral availability (phytase) or on the technological performance of Boughs (alpha-amylase). (C) 2008 Elsevier Ltd. All rights reserved.