Chinese name: β -amylase

Chinese alias: beta-amylase

English name: beta-amylase

English nicknames: beta-amylase (Sweet potato); The E.C. 3.2.1.2; Saccharogenamylase; Amylase, beta-

CAS no. : 9000-91-3

Appearance: Light yellow or white freeze-dried powder, soluble in water

EINECS no. : 232-566-1

Storage conditions: 2-8°C

Application: widely used in alcohol, liquor, beer, brewing, food processing, feed addition, leather processing, etc

β-amylase (β-amylase), also known as starch β-1, 4-maltosidase, is a kind of amylase, widely exists in barley, wheat, sweet potato, soybean and other higher plants, as well as bacillus and other microorganisms. It is the main saccharifying agent for beer brewing and malt syrup. High maltose containing 60%~70% maltose can be produced by saccharification of starch materials after acidification or liquefaction of β -amylase produced by microorganisms such as Bacillus polymyxis and Bacillus giant

β -amylase is an extraneous amylase, which acts on the separated α-1,4 bond successively from the non-reducing end of starch, and the hydrolyzed product is maltose. This amylase is called β -amylase because it changes the configuration of C1 in maltose molecule from α type to β type during hydrolysis.

β -amylase cannot hydrolyze the α-1,6 bond of amylopectin, nor can it continue to hydrolyze across the excessive fulcrum, so the hydrolyzed amylopectin is incomplete, and the β -limit dextrin of the macromolecule remains. When β -amylase hydrolyzes amylose, if the starch molecule consists of an even number of glucose units, all the final hydrolyzed products are maltose. If starch molecules consist of an odd number of glucose units, the final hydrolysis product contains a small amount of glucose in addition to maltose. When β -amylase hydrolyzes starch, there are always macromolecules from the end of the molecule, so the viscosity decreases slowly and it cannot be used as a liquefaction enzyme. However, when β -amylase hydrolyzes starch hydrolysates such as maltodextrin and maltooligosaccharide, the hydrolysis speed is very fast, so it is used as a saccharifying enzyme