Water is the perfect form of nature. Two hydrogens and one oxygen atom balance each other out to create one of the two most important natural resources. Since beer is approximately 95% water, brewers have to take great care of the brewing water.
Until the last decades of 19th century brewers did not know much about water chemistry. They simply brewed beer that best suited the local water. This is how lagers became popular in Prague, porters in London and IPAs in Burton on Trent. Today, water chemistry is well researched and it allows brewers to treat water according to the style they are brewing, no matter what their local water profile looks like.
There are six important minerals that a brewer looks for in his brewing water. Depending on the style brewed, the brewer can play with different level of these minerals in order to adjust the water according to his/her needs and the beer style brewed.
To demonstrate how each mineral affects beer here is a quick overview:
Calcium (Ca) - determines water hardness and acidifies.
Magnesium (Mg) - levels have to be kept in check since in larger amounts it contributes to unpleasant bitter flavor.
Sodium (Na) - enhances sweetness and adds fullness to darker beer styles.
Bicarbonate (HCO3) - helps brew better dark and hopped beers, adds alkalinity.
Sulfate (SO4) - helps highlight clean hop flavor and lightens the color of beer.
Chloride (Cl) - increases hop bitterness level and helps add fullness to beer.
Using the right water profile will highlight the ingredients used and have a positive impact on the overall beer impression. On the other hand, the wrong water profile can make some of the ingredients stand out less than it was desired once the beer recipe was created and the end result is a waste of time, effort and ingredients. In short, when you treat brewing water with care, you actually take good care of the beer. And beer deserves to be taken great care of, because it is a real treat.
