Water (or liquor as we say in brewing circles) makes up as much as 97% of beer so it doesn't take a genius to work out that it's important to ensure it has the right characteristics.
Of all the topics within brewing, this one causes the most confusion. It is perceived as a highly technical arcane subject, requiring joint doctorate degrees in nuclear physics and pure mathematics; whereas in reality it can be very simply stated as reduce the alkalinity to that required for the style, and increase the calcium to that required to ensure the brewing process proceeds efficiently. Fundamentally there is very little point, beyond the empirical exercise, to trying to match a liquor to a 'published' profile, as there are often several, wildly differing, published water profiles for brewing regions, and the brewers in those regions often adjust or treat that water before using it for brewing.
It is important to realise that unless you have a sound grasp of good brewing techniques no amount of water treatment is going to magically improve your beer, or indeed help make your first all grain beer taste exceptional. Before even considering water treatment, brewers, new and old, need to have a good grasp of how their brewing 'kit' works, and be able to consistently produce reasonable beer. Once you can do this, then it is worth looking at whether or not water treatment can make a significant improvement to the beer.
Over the years I have been brewing, I have read many books and articles on water treatment, and it has become apparent to me that the purpose of this information is to persuade the brewer that they need to match the water profile of a region in order to brew a beer similar to those produced in the brewing region. This is simply untrue, and leads to unnecessary over complication, as mentioned earlier in the article there are only really two (well three if you want to be picky) fundamental principles to water treatment, and these will be covered in a further series of articles in later issues.
Firstly, remove any chlorine from the liquor. The easiest way to do this is to use a Campden tablet in 10 gallons of liquor. This instantly disperses chlorine, adds a tiny amount of chloride and sulphate.
Secondly, measure and adjust the alkalinity to a level that suits the beer being brewed, pale ales need an alkalinity no higher than 30mg/L and preferably lower than this, Brown ales and milds can get away with a level of 50mg/L, and stouts and porters up to 100mg/L.
Lastly, Ensure that there is sufficient calcium left in the liquor to ensure the important brewing reactions that take place in the mash tun, copper and fermenter do take place. The minimum level is around 60mg/L, but levels much higher than this are fine, I usually aim for 120 to 150mg/L, as I find in an all pale grist this gives me a mash pH of 5.3 which is really the prime purpose of water treatment.
Water treatment is another useful weapon in the all grain brewers arsenal, but there is a distinct lack of simple and easy to understand instructions on what needs to be done and when to assist brewers in coming to grips with it. Hopefully with these articles, I will show that it can be very simple, but just throwing chemicals into the liquor at 'random' is not the ideal approach.
Thanks to Aleman for most of the text on this page.
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