Rheological properties of short doughs at large deformation

Large deformation rheological properties of short doughs of various composition were determined in uniaxial compression. Apart from a sugar-ii-ee dough, all doughs studied showed pronounced yielding and flow behaviour. Yielding occurred at very small strain, indicating strong strain dependence. At small strain, systems were predominantly solid-like; at large strain they behaved more like strain-rate thinning liquids. The doughs showed large differences in apparent biaxial extensional viscosity, depending on fat and sucrose contents. It is concluded that yielding behaviour is strongly influenced by intact flour particles that act as defects in the material. The occurrence of such particles is determined by the presence of sucrose, which delays gluten development through its effect on solvent quality. The sucrose also facilitates formation of a non-fat continuous phase, since it increases the quantity of solvent. (C) 1999 Academic Press.