Computational modeling of dough sheeting and physical interpretation of the non-linear rheological behavior of wheat flour dough

Controlling the dough sheeting processes has been a long standing challenge in the food industry. This paper presents the results of a study aimed at developing a validated finite element model for simulating dough sheeting processes. An instrumented, two-roll dough sheeter was constructed to measure roll forces and dough thickness during sheeting. To develop a rheological model, true rheological properties of dough were measured in compression and extension. A filament stretching device was constructed to obtain consistent data for dough extension. Results showed dough to be a non-linear, rate-dependent material that was capable of undergoing large deformations with only moderate elastic recovery. Freshly mixed dough had additional complexities of anisotropy and Mullins softening. The Bergstrom-Boyce model, which has been known to capture large deformation behaviors of lightly cross-linked elastomers, was modified to include anisotropy and Mullins softening and applied to dough. The sheeting process was modeled in finite element simulations as a plane-strain rolling operation using the commercially available software, Abaqus. The simulation predictions were in good agreement with experimental data for both roll forces and dough thickness. Techniques for controlling dough flow rates utilizing on-line, roll force measurements have been projected. Future studies for delineating sheeting effects on dough structure have been identified.