Food extrusion entails a bioreactor system that pushes several mixed ingredients through a narrow, shaped opening, known as a die (Lisch and Launay 1893) to form various products, referred to as extrudates (Berek, 2009).
Hot, cold, co-extruded, and steam-induced extrusion are among the main categories used in the food extrusion processes worldwide. Foods that go through the extruder system are usually transformed into a melted state by the high temperature, high shear, and high pressure environment created by the single or multiple sets of screws, encased inside the barrel. When the mixture being extruded out of the system encounters a sudden drop in the temperature and pressure, it expands and forms into a cooked product.
What Makes the Food Extrusion Technology So Special?
Extrusion technology has quickly spread into several areas of food processing and manufacturing. Roller-type, screw, and piston extruders are some of the most common types of extruders used across the food industry. Initially, these extruders were used to process sausages and meats, especially piston extruders; however they were quickly replaced by screw extruders to streamline the process.
Screw extruders typically utilize multiple, single, or twin screws that rotate within a metal cabinet, known as the barrel. These screws are responsible for channeling the ingredients forward to make them pass through an orifice (the die) so that it can take on different sizes and shapes.
When single-screw extruders began to be used in pasta production, the innovation revolutionized the food industry with exceptional functionality and speed (Ainsworth, 2011). It made professionals working in the food industry discover the potential of extruder systems in diversifying food extrusion options, leading to expansion and invention of several foods, back in the 1980s.
Today, extruders offer incredible amounts of functionality and variability with significantly high efficiency and low production costs compared to most other food processing methods. They’re widely used for production of several types of RTE pasta, cereals, chewing gums, snacks, aquatic feeds, pellet products, baby and pet foods, among hundreds of other food products.
How Has The Extrusion Process Revolutionized The Food Processing Industry?
Data reveals that the extruded food market worldwide has grown at the rate of more than 4% during the last few years. Many expect this growth to continue as emerging markets keep on developing due to increased urbanization and the busy lifestyle led by most people across the globe.
From fibrated proteins, such as plant-based, texturized ‘meats’ to third-generation ‘half-products’ that can later be fried, popped, or puffed, food extrusion technology has enabled consumers to immerse in new culinary experiences. The process has also helped pet parents ensure they feed their pets with extruded food that is packed with nutrition but also affordable.
As people are choosing to move towards making more sustainable choices, food extrusion offers convenient yet healthy food options that are ethically produced to ensure premium quality. Since extrusion has proven to me more economical, versatile, and efficient, it not only plays a critical role in the food extrusion industry currently, but also seems to have a bright future.
If you’re looking to invest in an advanced extruder processing technology, check out the sophisticated food and feed processing technologies at CFAM Technologies (Pty) Ltd. From extruder operation and maintenance to extruder operational training and specialized machine designs, we offer complete packages to help you streamline your food processing or waste processing plant.