Amylase

Amylase is an enzyme in flour, malt and yeast that breaks starch down into sugars, feeding the yeast and helping crusts brown.

Amylase: A small pile of pale diastatic malt flour heaped on a plain surface beside a round of risen bread dough.
  • Food science and baking chemistry

Also called diastase, amylase is an enzyme that, under the right conditions, breaks up some starch, liquefies it, and converts it into malt sugar. In dough this supplies food for the yeast and sugars that help brown the loaf.

Flour carries some of it, and bakers can add more with malt flour: diastatic malt is dried at a low temperature so that it keeps the activity of its diastatic enzymes. Research on flour with high levels of damaged starch adds that damaged granules are more hydrolyzed by amylases, which is why amylase preparations are tested to offset dough and bread problems from that flour.

The enzyme has a limit. A baking textbook states that amylase is destroyed at about 170°F (77°C) during baking, at which point the dough stops expanding.

Related entries

Sources

Written by VanillaGoods in our own words from these sources. Last reviewed October 15, 2026.

  1. 4.4: Enzymes, LibreTexts (Understanding Ingredients for the Canadian Baker, open college textbook)
  2. 2.9: Malt, LibreTexts (Understanding Ingredients for the Canadian Baker, open college textbook)