ALDC - Alpha Acetolactate Decarboxylase (ALDC) prevents the formation of diacetyl by breaking down the precursor, alpha acetolactate, as it is formed during fermentation – converting it quickly and directly into acetoin. Since diacetyl can be formed from the precursor in the finished package, adequate removal helps ensure the product retains the intended quality.
ALDC can also help to reduce the rate limiting step in conditioning. Only 1 to 5 grams per barrel is required to be added to cold wort, prior to yeast pitching. As this enzyme is pH sensitive it is deactivated by the normal pH drop at the end of fermentation