Ruminal digestion of starch: factors of structural and microbial origen
Abstract
Starch is a condensed polymer of glucose formed by amylose and amylopectin. The starch granules present amorphous and crystalline regions. The use of HPLC indicates that amylopectin has a polymodal distribution of the glucose chains. Starch is hydrolyzed in the rumen by several amylolytic enzymes, releasing oligosaccharides, maltose and small amounts of glucose. The amylolytic enzymes are present in bacteria and protozoa, and the enzyme activity vanes depending upon the forage level and grain type in the diet.