Extrusion-cooking may be defined as "the process by which moistened,
expansile, starchy and/or proteinaceous material(s) are plasticized in a
tube by a combination of pressure, heat, and mechanical shear. This results
in elevated product temperatures within the tube, gelatimzation of starchy
components, denaturation of proteins, the stretching and restructuring of
tactile components, the shaping of the end products and the exothermic ex
pansion of the extrudate" - Smith (1974).