Effect of extrusion processing on starch gelatinisation and performance in poultry

Starch, the major source of carbohydrates in commercial avian diets, is the most abundant storage polysaccharide in plants. Native starches differ in granule size, amylose to amylopectin ratio and amylose structure. Extrusion in simple terms is a process of cooking under pressure, moisture and elevated temperature. There are several effects of extrusion processing on protein, lipid and starch by changing physical, chemical and nutritional properties. Yet, starch plays a key role during extrusion, and undergoes several significant structural changes, which include starch gelatinisation, melting and fragmentation. Related literature gives no consensus on the impact of extrusion processing; hence this review will give an overview on factors affecting gelatinisation degree of starch and the effects of extrusion processing on performance and nutrients digestibility in poultry.