Lactic Acid lowers mash pH and is best added to brewing water before dough-in of malt bill. Perform the calculations first to determine the correct amount. Lactic Acid is potent and a little provides a significant amount of acidity. Often utilized in conjunction with mineral salts to reach an overall mash pH of 5.1 – 5.6 at mash temperature.
Beyond mash pH, Lactic Acid is often utilized in the reduction of sparge water pH. Small additions to sparge water prevents pH rise in the mash near the end of lautering and run-off operations, averting the extraction of tannins from the husks of the mashed grain.