Describe the role of alpha-acetolactate decarboxylase in preventing diacetyl formation, detailing the specific enzymatic reaction it catalyzes.

Alpha-acetolactate decarboxylase (ALDC) plays a critical role in preventing diacetyl formation by converting alpha-acetolactate, a precursor to diacetyl, into acetoin. Diacetyl is an unwanted compound in many fermented beverages, imparting a butterscotch or butter-like flavor that is considered an off-flavor in most beer styles, some wines, and certain ciders. During fermentation, yeast produces alpha-acetolactate as an intermediate in the biosynthesis of valine and isoleucine, two essential amino acids. Alpha-acetolactate is initially non-volatile and does not con....