pyruvate
From The Oxford Companion to Beer
is the molecule produced as the end point of the glycolytic breakdown of glucose. It is a three-carbon compound formed by yeast cells during fermentation. When the yeast cell grows under anaerobic conditions, the pyruvate is converted into carbon dioxide and acetaldehyde. From there, during normal brewery fermentations, acetaldehyde will be converted to ethanol.
Bibliography
This definition is from The Oxford Companion to Beer, edited by Garrett Oliver. © Oxford University Press 2012.