β-amylase

β -amylase

Amylase is a general term for enzymes that hydrolyze starch and glycogen. According to the different ways of hydrolyzing starch, amylase can be divided into four categories: α-amylase, β-amylase, debranching enzyme and glucoamylase. According to the difference in structure, it can be divided into two categories: a-amylase and β-amylase. In recent years, the research on β-amylase has attracted widespread attention in the enzyme preparation industry. β-amylase is widely found in higher plants such as barley, wheat, sweet potato, and soybean. At present, most of the commercial β-amylase is extracted from plants, and the production of Bacillus β-amylase is extremely low.

Properties of β-amylase.

β-amylase is an amylase that can decompose straight-chain starch into maltose. It is acid-resistant. Adjusting the pH value of the wort to 3.6 can make α-amylase lose its activity at 0°C, and β-amylase remains. The only product of β-amylase is maltose, not glucose. β-amylase hydrolyzes starch to produce maltose. For a long time, β-amylase has been mainly derived from grain crops such as barley. The application of β-amylase produced by microorganisms is limited. It can completely or partially replace plant-derived β-amylase to produce high maltose syrup, high-purity maltose, medical injection maltose, maltitol, maltodextrin, beer, etc.

Applications of β-amylase.

β-amylase plays an important role in food processing, grain processing, fermentation, brewing, medicine, textiles and other industries.

β-amylase, as a saccharifying agent, can be used in industrial production of beer, maltose, beverages, etc. It is an important enzyme source in the food processing and brewing industries. Microbial β-amylase is used to replace part of the barley malt in the beer production process, and the ratio of barley malt to rice is changed from 7:3 to 5:5 to add microbial β-amylase. The synergistic effect of malt amylase and β-amylase can produce ultra-high maltose syrup.

Usually in the sugar production, β-amylase produces maltose by hydrolyzing starch, and is mainly used in the production of maltose syrup, high-purity maltose, maltodextrin, maltitol, medical injection maltose, etc. Maltose is a common disaccharide in nature, and it is the main component of maltose syrup. Maltose is not only widely used as a sweetener, but also a medical intravenous infusion sugar supplement. At the same time, because of the low crystallinity and low hygroscopicity of maltose, it is also widely used in food industry production. Corn, potato, sweet potato and cassava starch can all be used as raw materials for the production of maltose.

In the brewing industry, β-amylase is one of the main saccharifying enzymes. For example, in beer production, the main enzyme preparation used in the production of special syrup is β-amylase, which plays a key role in the quality, variety and cost of beer syrup. Using β-amylase to replace malt in beer production can increase the auxiliary material ratio to 50%~75%, which saves malt usage, increases saccharification rate, and reduces production costs. The beer produced is light in color, white and delicate foam, clear and transparent, of excellent quality, and refreshing and pure taste. Compared with beer produced by conventional processes, it can also reduce production costs.

In addition, β-amylase is also used in the pharmaceutical industry.