Description
Lactic Acid is used in beer brewing to lower the mash or sparge pH, this helps to reduce tannin extraction during the sparge keeping the sparge runoff below 5.8pH.
It is also used to pre-acidify wort before adding souring bacteria like lactobacillus, this helps reduce the chance of wild bacteria growth due to the much lower pH.
Traditional brewers prefer to use Lactic Acid as it is a natural byproduct of souring fermentation. Whereas new world brewers prefer to use Phosphoric as they can use less of it for the same function.
It is advisable to use the RAPT Recipe Builder or BrewFather to determine how much acid to use in your Mash and Sparge.