Water – the forgotten ingredient
Its funny because homebrew authors and bloggers alike talk a lot about yeast, hops and malt but very little time is given to the ingredient that makes up over 90% of a brew – the water. Water chemistry has a strong influence on the mouthfeel of an ale and has a big say in the performance of the fermentation and final conditioning of an ale.
Major brewing industries have grown up around geologically favorable sites with the right mix of rock type to filter the water from naturally occurring springs and wells and supply the optimum minerals from brew water. Areas such as London and Burton on Trent in the UK, the Czech town of Pilsen, and the towns of Dortmund and Munich in Germany have very distinct water favorable to the brewing of specific styles of beer. In John Palmers online reference “How to Brew” he outlines how the water chemistry found in these towns is balanced with the malt and hops to make the distinctive beers such as Guiness and Pilsner.
Pilsen – The very low hardness and alkalinity allow the proper mash pH to be reached with only base malts, achieving the soft rich flavor of fresh bread. The lack of sulfate provides for a mellow hop bitterness that does not overpower the soft maltiness; noble hop aroma is emphasized.
London – The higher carbonate level dictated the use of more dark malts to balance the mash, but the chloride and high sodium content also smoothed the flavors out, resulting in the well-known ruby-dark porters and copper-colored pale ales.
Burton-on-Trent – Compared to London, the calcium and sulfate are remarkably high, but the hardness and alkalinity are balanced to nearly the degree of Pilsen. The high level of sulfate and low level of sodium produce an assertive, clean hop bitterness. Compared to the ales of London, Burton ales are paler, but much more bitter, although the bitterness is balanced by the higher alcohol and body of these ales.
There are two important ingredients found in brewing water. The first is Calcium which helps create the acid required to balance out the alkaline phosphates in the malt. Acidity is needed to promote enzyme activity in the wort and to promote flavour, clarity and stability to the finished beer. The second ingredient is Magnesium and important yeast nutrient in small doses.
Most homebrewers do not have access to abundant naturally purified fresh spring water or wells. We make do with the towns best, tap water. Unfortunately tap water can contain ingredients that are not favorable to the brewing process. Chlorine is used to prevent the build up of bacteria in the water supply but in high doses can lead to bitterness in beer and can kill the yeast.The good news is Chlorine is highly volatile and can be removed by simply boiling.
So how do we as homebrewers begin to think about the water we use to brew our ales? A good first step is to grab a copy of your towns water quality report and check the level of hardness (found in the Calcium and Magnesium levels) and the level of Chlorine. In many cases the answer will be nothing, the Chlorine will come out during the boil along with any other impurities and most town water falls within acceptable levels of water hardness.
If you want to check the pH level of your brew water buy a pH testing kit from your homebrew supplier and check the level of the wort during a boil. I take a sample using a turkey baster. Make sure the wort is properly cooled to ensure an accurate reading. An optimal reading is in the 5.0-5.5 range. If the levels are outside you can use calcium carbonate to make more alkaline or an acid. The pH levels will only change between 0.2-0.3 during the boil, so you will be all set once the pH in the acceptable range.
For those who really want to optimize the water mineral content to match the style of beer being brewed consult the chart and attached spreadsheet on John Palmers site here.
Given this is the BritishBrewer and we focus on classic British ales is there an effective and simple way to replicate the water of a London or Burton? The quick answer is yes and I have been playing around with various techniques including adding calcium and gypsum. But I finally stumbled upon a magical little powder called Burton Salts, containing all the essential minerals in a single package. The process is simple, for a 5 gallon batch:
- The night before you intend to start the brew bring to the boil 6.5 gallons of tap water in the kettle, this will remove all the unwanted chemicals and purify the water
- Add the recommended dose of salts, then check the pH (again ensure the water has cooled). This is a bit of a chicken and egg situation because it is hard to predict the final pH level of the wort once malt and hops have been added. I find a pH level for the brew water of 5.8 works for me. Remember to check the wort pH on brew day and make adjustments for your next brew. You can also adjust the pH of the wort by adding more salts.
- Now boil the water for 15 mins
- Once boiled leave the water to cool ready for brew day
Water treatment really does make a difference, the brew flavours are sharp and fresh and the colour brighter. Have fun and over the next few weeks we will begin a review of different malt types and start a series of deeper dives into some favorite British Brew styles, their history and some classic recipes.
