Strong Balanced Brew – When you mash 100% base malt grist with distilled water, you will usually get a mash pH between 5.7-5.8. (Remember, the target is 5.1-5.5 pH.) The natural acidity of roasted speciality malt additions (e.g. caramel, chocolate, black) to the mash can have a large effect on the pH. Using a dark crystal or roasted malt as 20% of the grain bill will often bring the pH down by half a unit (.5 pH). In distilled water, 100% caramel malt would typically yield a mash pH of 4.5-4.8, chocolate malt 4.3-4.5, and black malt 4.0-4.2. The chemistry of the water determines how much of an effect each malt addition has. The best way to explain this is to describe two of the world’s most famous beers and their brewing waters. The Pilsen region of the Czech Republic was the birthplace of the Pilsener style of beer. A Pils is a crisp, golden clear lager with a very clean hoppy taste. The water of Pilsen is very soft, free of most minerals and very low in bicarbonates. The brewers used an acid rest with this water to bring the pH down to the target mash range of 5.1 – 5.5 using only the pale lager malts.
