α - Amylase - This enzyme is an endo hydrolase; it hydrolyzes starch into components, which have three or more linear α -1, 4-gulcan units. It stops hydrolysis when fragments with 2-6 glucose units remain; typically, such fragments contain an α -l,4-6 linked branch point residue.

The end products of starch hydrolysis are dextrins, which are used as adhesives and thickening agents in prepared foods. α -Amylase must be used at high temperatures. The enzyme from Bacillus licheniformis can be used for prolonged periods at 95°C and for a brief period at 105-110°C.