Rating Newest Oldest. Best Answer: Alcohol and lactic acid fermentation take place in the cytoplasm, the site of glycolysis, the reaction that precedes them. The reactants are the pyruvates left over at the end of glycolysis, the products are ethanol in alcohol fermentation and lactic acid in lactic acid fermentation. These two reaction produce zero ATP--their entire function is to reset the cellular machinery so glycolysis can occur again.