In-line Measurement of the Viscous Behaviour of Wheat Starch During Extrusion. Application to Starch Cationisation

Abstract

A specific twin channel slit die was used to measure in-line the viscous behaviour of an extruded wheat starch. This allows to put in evidence the influences of temperature, water content and specific mechanical energy (SME). The proposed rheological law permits to satisfactorily predict the viscosity of a wheat starch for any processing condition. Original results are presented for the behaviour of cationic starches obtained by reactive extrusion.

Keywords

• wheat starch
• slit die
• twin screw extrusion
• specific mechanical energy
• cationisation