Enzyme preparations are derived from organisms and are generally safer and can be used in appropriate amounts according to production needs.There are three major groups of microorganisms that produce enzyme preparations: filamentous fungi, yeasts, and bacteria, mainly using good air bacteria.The strains and usage of several main industrial enzymes are as follows:
(1)Amylases
Amylase hydrolyzes starch to produce pasty malto-oligosaccharides and maltose.It is mainly produced by submerged fermentation of Bacillus subtilis and Bacillus licheniformis of the genus Bacillus, and the latter produces thermostable enzymes.In addition, it is also produced by submerged and semi-solid fermentation with strains of Aspergillus and Rhizopus, which is suitable for food processing.Amylase is mainly used for sugar making, textile desizing, fermentation raw material processing and food processing.Glucoamylase can hydrolyze starch into glucose, which is now almost all produced by Aspergillus niger submerged fermentation for sugar production, alcohol production, fermentation raw material processing, etc.
(2)Protease
The most used strains and production varieties.Use Bacillus licheniformis, Bacillus pumilus and Bacillus subtilis to produce bacterial protease by submerged fermentation; use Streptomyces and Aspergillus submerged fermentation to produce neutral protease and Aspergillus acid protease for leather depilation, fur softening, pharmacy and food industry;Some bacteria of the genus Mucor undergo semi-solid fermentation to produce rennet, which replaces the rennet originally extracted from the calf stomach in the manufacture of cheese.
(3)Glucose isomerase
A variety that developed rapidly in the 1970s.First, submerged fermentation is used to obtain Streptomyces cells. After immobilization, the glucose solution is converted into a syrup containing about 50% fructose. This syrup can be used in the food industry instead of sucrose.Using amylase, glucoamylase and glucose isomerase to produce fructose syrup from corn starch has become one of the emerging sugar industries.
