Migration of gluten under shear flow: Influence of process parameters on separation behaviour

The effect of processing conditions on the shear-induced migration of starch and gluten was described. A shearing device was used to induce a separation of wheat dough into a gluten rich fraction and a starch phase. A two-stage mechanism for separation was observed: first local aggregation of gluten, followed by migration of the gluten domains to the apex of the cone. The process was not strongly influenced by variations in the process conditions, possibly because a change in process parameter could have opposing effects on stages 1 and 2. Severe process conditions can lead to gluten damage and thereby a reduction in the driving force for separation. A relatively low temperature (10–15 °C) and low rotational speed (10 rpm) had a positive effect on the gluten migration inside the shearing device. A simple model was proposed to explain the effect of process parameters on the second stage of the gluten migration process.