Amylases are enzymes that convert starch to sugar.
They occur naturally in plants, saliva, pancreatic juice, and microorganisms. Bakers add amylase to bread dough to supplement the small amount found naturally in wheat flour. The sugar that the amylases produce serves as food for the fermenting yeast and also makes for better-tasting, better-toasting bread. Amylases also improve the dough's consistency and the bread's keeping quality.