Αlpha-amylase obtained from thermo-resistant bacteria like Bacillus licheniformis, engineered strains of Escherichia coli or Bacillus subtilis is used during the first step of hydrolysis of starch suspensions. For amylases to attack starch,
these suspensions should be brought to high temperatures (90 – 110oC) for the breakdown of starch kernels. Apar and Ozbek (2004) provide information about the effects of operating conditions on the enzymatic hydrolysis of corn
starch using commercial α-amylase.