Sour malt aka Acidulated Malt, is a malt that contains a small amount of lactic acid (around 1 – 2%). This malt was traditionally used to achieve the proper mash pH in cities with very alkaline water. Typical usage rates do not exceed 10% of the total mash, and Swaen recommends only up to 5%. To estimate acid adjustment assume 1% acid malt to reduce pH by approximately 0.1 as a general rule.
5°L