Extrusion is a very common processing technology used in the food industry to produce direct expanded snack foods, cereals, and pet foods, among other products. Extruded products are typically made by utilizing a raw material, often flour, and subjecting it to high temperatures while also creating a high shear and high pressure environment using rotating screws.

This introductory course will provide information about the extrusion processing systems, extruder parts, basic heat and mass transfer, extruder screws and dies, food ingredient functionality (with a focus on pulse ingredients) and food product development with extrusion. The course will provide practical examples of product development with extrusion using pulse ingredients.

Extrusion is a very widely used technology in the food industry. Some of the common food products made with extrusion technology include snacks, breakfast cereals, flat breads, bread crumbs, pellet products, textured vegetable proteins and many others.

It is a complex process with multiple inputs variables. Extrusion can be viewed as a reactor with a short residence time and with numerous options to control the energy inputs. The food ingredients in extrusion undergo physico-chemical changes as they are subjected to mechanical shear and heat. These physico-chemical changes transform them into the products with different eating characteristics.