The rheological behaviour of three different commercially manufactured chocolates are studied as a model paste system in order to understand their processing characteristics at different temperatures by using parallel-plate and capillary flow. The rheological behaviour is distinctly different at temperatures below and above 30 degrees C. At temperatures below 30 degrees C it behaves as a soft solid. A previously developed phenomenological mathematical model for polytetrafluoroethylene (PTFE) paste flow was used to model its rheology and capillary extrusion. The model takes into account the elastic-plastic (strain hardening) and viscous nature of the material in its non-melt state. The predictive capability of this model is tested against capillary data for a variety of capillary dies having different length-to-diameter ratios (L/D) and contraction angles (2 alpha). At temperatures above 30 degrees C, chocolate behaves as a visco-elasto-plastic liquid. Its behaviour has been determined as a Herschel-Bulkley viscoplastic material with a small degree of thixotropy. The rheological data obtained from parallel plates and bob-cup rheometer were used to formulate a thixotropic model using a structural parameter. The capillary data were found to be well described with the proposed models. (C) 2014 Elsevier B.V. All rights reserved.