In the search to make feed production more sustainable, extrusion process is a technology that cannot be ignored. Accurate analysis and continuous optimization of extruded product components and raw material ingredients will remain an active field of research and development in the future, as the main goal of extrusion is to increase nutrient availability and digestibility, i.e. to improve animal productivity.

In this file; effects of protein, starch, fat and fiber amounts in raw materials such as wheat, rice, corn, soybean, barley and oats on extrusion will be examined.

In extrusion process, proteins begin to lose their functionality after 55-65°C. Water solubility, durability, and expansion contribution properties of proteins decrease. On the other hand, proteins preserve their nutritional value up to 130°C. At higher temperatures, protein in the contents begin to be damaged by heat and their nutritional value decreases.

Briefly; as temperature increases, the amount of protein damaged by heat increases, while the amount of soluble protein decreases. The optimal point of this inverse ratio is ~150°C.

The contribution of starch to the product in terms of adhesion and durability is very high. Starch granules begin to swell by absorbing water at 60-75°. As heating continues, this swelling becomes irreversible, the natural crystalline structure becomes dispersed and the starch becomes more soluble. If a light-density product is desired, increasing the amount of starch will increase swelling. For a strong and durable product, increasing the amount of starch will increase adhesion.

Fat is added to provide additional calories, to improve palatability, to provide nutrients such as fatty acids, to carry fat-soluble vitamins and to control dust. It reduces friction between products in the recipe and between the recipe and the internal components of the extruder. As friction decreases, the mechanical energy required decreases as well. Less expansion takes place. In other words, an increase in the fat amount of the content causes an increase in the bulk density of the product.

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• Effect of Protein, Starch, Fat and Fiber in Extrusion
  In the search to make feed production more sustainable, extrusion process is a technology that cannot be ignored. Accurate analysis and continuous optimization of extruded product components and raw material ingredients will remain an active field of research and development in the future, as the main goal of extrusion is to increase nutrient availability and digestibility, i.e. to improve animal productivity.
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