Due to the high demand for animal products, animal feed is a critical component of the global food industry. In fact, it’s one of the largest sectors of the food manufacturing systems. Therefore, food industries must ensure safe and affordable production of animal proteins. Extrusion is an essential part of sustainable animal feed composition.
It’s a high-temperature process that compacts and cooks animal feed with high humidity levels, temperature, and pressure within a minimal amount of time. The goal of animal feed extrusion is to achieve the desired level of food expansion and granulation to obtain a high-quality product. A stable animal feed extrusion process involves adding the mixture of ingredients to advanced food manufacturing machines such as single-screw and twin-screw extruders.
Starch gelatinization
Extrusion transforms the food starch in two ways. It first gelatinizes the mixture’s food ingredients by breaking up the starch molecules’ crystals, expanding the animal feed materials. When these starch crystals absorb the food’s water content, they break the expanded starch particles, turning them into a gelatinized melt.
The extruder’s pressure drops as soon as it releases the food components, excreting steam. When the extruded starch granules isolate from one another, they begin to form a micro-porous feed in the shape of gelatin.
Moreover, the starch degradation throughout this process diseases its average molecular weight.
Fat degeneration
Extrusion is a high-intensity process that destroys the oil seeds’ cellular structure, releasing fats and oily substances. The animal feed’s expansion produces a compound fat product like lipoprotein made with a combination of starch and proteins.
These nutrients can significantly minimize the mixture’s free fatty acid content, prevent oil degradation, and help avoid the food components’ spoilage after being stored and packaged.
The fat regeneration process through extrusion boosts the shelf life of animal food, promoting its long-term preservation.
Enhanced feed digestibility
The purpose of constant animal feed extrusion is to obtain animal food that offers increased digestibility and nourishment. The final extruded product has a fresh aroma, crispness, and minuscule granularity. The expansion of food materials creates spare space for enzyme production, increasing the contact of starch chains and digestive enzymes.
The production of digestive nutrients ultimately improves the feed’s palatability and edibility.