In this study, hazelnut testa was added to wheat flour bread to increase the dietary fiber content. Rheological and baking properties of hazelnut testa-wheat mixed flours were investigated. Farinographic and extensographic studies showed that water absorption, development time (except for 5%, fine, hydrated hazelnut testa), stability, time to breakdown, energy (highest in 5%, fine, hydrated hazelnut testa), resistance to extention, maximum resistance increased as the amount of hazelnut testa increased, while degree of softening, mixing tolerance index (MTI) and extensibility decreased at 5% and 10% of hazelnut testa substitution. Hazelnut testa breads had similar or slightly smaller specific volumes than the control breads. The differences among the crust and crumb colour of control and hazelnut testa breads were significant (P < 0.05). Breads were subjected to sensory evaluation for volume, crust colour, structure, symmetry, uniformity, colour homogenity, crumb grain.. crumb texture and taste/flavour. Increasing levels of hazelnut testa and hydradation process caused slightly decreases in total sensory scores. Detrimental effects of hydrated hazelnut testa on bread properties were excessive. But all bread samples except for bread samples produced from 10% hydrated hazelnut testa were considered acceptable. (c) 2006 Elsevier Ltd. All rights reserved.