Improvement of brown bread quality by prehydration treatment and cultivar selection of bran

Different bran pretreatments and bran cultivars were investigated with the aim of alleviating the adverse effects caused by bran addition in brown (fiber-rich) bread. Three different bran treatments: hydration, wet heat, and wet oxidation, all hydrate bran before its addition to other breadmaking ingredients. Four different bran cultivars were investigated. All treatments improved brown bread quality significantly, resulting in larger, softer loafs. All treatments resulted in an increase in the water absorption of brown bread doughs and a decrease in potentially oxidizable substances (POS) in brans. It is suggested that prehydration treatment activates bran lipoxy-genase which oxidizes POS in bran, reducing bran's contribution to brown bread dough. A further reduction of these substances is caused by a washout effect of the treatments. On average across all bran cultivars, the hydration and wet oxidation treatments improved brown bread quality significantly more than the wet heat treatment, which also reduced the bran POS significantly less than the other treatments, probably due to its rapid inactivation of lipoxygenase, The bran cultivars differed significantly in their effects on brown bread quality, suggesting that bran selection according to cultivar should be considered.