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Though the rheology of wheat flour doughs has been extensively studied, dough rheological characterization remains incomplete. This characterization is necessary for process optimization as well as for wheat genetics research. During processing dough undergoes shear and extensional deformations. Both types of deformations have been used to measure dough rheological properties, but a unifying model is still needed. The objective of this work is to develop a constitutive rheological model for wheat flour dough. A Lodge-type model taken from the polymers area is used to predict the stress-strain behavior of dough. To determine the model's applicability, doughs are made at various moisture contents from three commercially blended flours with very different properties (pastry, bread and durum flours) and tested under both small and large deformations. Small deformation shear measurements obtained in the linear viscoelastic region give G' values on the order of 10-30 kPa. These G' results are then fitted to a generalized Maxwell model to yield relaxation times on the order of 0.1 to 30 seconds. Parameters obtained from the small deformation tests - relaxation times and rigidity moduli - are incorporated in the model. Results of the model are then compared to those obtained from large deformation planar extensional tests conducted on a universal testing machine, where peak stresses of 0.75 to 4.0 N are observed. The constitutive model successfully predicts the magnitude of the stress and the strain hardening observed in the planar extensional tests. However, the model is unable to predict the dough's failure point.