Biochemistry

Amylopectin molecule site (a-1,6 type bond) Dextrins - fragments of starch and glycogen molecules - soluble substances that are easily absorbed by the human body. Partial hydrolysis of starch occurs during cooking of plant products and during baking. Hydrolysis of starch occurs gradually'. +H2O +H2O +H2O HO[C 6 H 10 O 5 ] x H — ► nHO[C 6 H 10 O 5 ] y H — * mHO[C 6 H 10 O 5 ] z H “ * Starch Erythrodextrins Achrodextrins — ► pHO [СбНіо0 5 ] га — ► (C 6 H 12 O 6 ], where x > у > z > m Maltodextrins Glucose The processes of dextrinization and saccharification of starch are used in the food and alcohol industries. During enzymatic hydrolysis of starch, dextrins also form in the digestive tract, some of them (after eating foods rich in carbohydrates) arc absorbed by the walls of the small intestine and enter the blood of the portal vein of a person. Amylose is hydrolyzed by a-amylase of saliva and pancreas. Amylopectin is hydrolyzed by a- and fl-amylases. Glycogen ( “ animal starch ” ) is the main reserve polysaccharide of humans and higher animals. In its structure, it is close to amylopectin and consists of glucose residues. In the main chain, they are connected by type 1.4, side branches come from sixth carbon atoms (1,6-bonds). With iodine, glycogen gives a reddish-brown staining; during hydrolysis, it is split into dextrins, maltose, then glucose. The glycogen contained in organs and tissues is a mixture of polysaccharides of 149