Effect of Extrusion on the Functional and Pasting Properties of High-quality Cassava Flour (HQCF)

Cassava is a rich source of starch and is used as a food ingredient and additive. In its natural state, cassava flour or starch cannot meet all functional requirements in food processing. This necessitates the modification of starch to meet specific functional requirements for products and processes. This study investigated the effect of different extrusion conditions, such as moisture content, screw speed, and temperature on the functional and pasting properties of high-quality cassava flour (HQCF). Particle size distribution, functional and pasting properties of the HQCF were determined. Moisture content (MC) had a significant effect on the properties of HQCF. Water absorption capacity (WAC) increased from 245% to 732%, swelling power (SP) increased from 3.4 g/g to 7.2 g/g, and water absorption index (WAI) increased from 3.0% to 3.3% after extrusion at 40% MC. While at lower MC levels, bulk density (BD) increased from 0.7g/ml to 0.8g/ml for the non-extruded and 30% MC; oil absorption capacity (OAC) from 215% to 253% for the non-extruded and 10% MC; water solubility index (WSI) from 6.0% to 56% for the non-extruded and 20% MC respectively. A positive correlation was observed between extrusion parameters and functional properties. The results suggest that manipulation of extrusion conditions can be used to modify HQCF for varied food applications.