ABSTRACT
Ready-to-eat cereals and pasta products have been the main application of extrusion in the technology, but it has expanded into the preparation of dry and semimoist pet foods, snacks, confectionery products, chewing gums, modified starches, dry soups and beverages, and texturized vegetable proteins. Extrusion can be considered a shaping process by forcing a product through a die, a high-temperature-short-time (HTST) thermal process, a cooking technique, or a bioreactor in which chemical reactions involving natural biopolymers of a food system take place. Some of the advantages of extrusion described by J. M. Harper are its versatility, high productivity, low cost, ability to form different shapes, high microbiological quality, and nutrient retention due to the HTST process. Several types of extruders have been developed for food processing; the simplest ones contain a single screw, and the increasingly complex ones possess various twin screw arrangements. The laboratory practice will focus on the study of the performance of a single screw device.
