At first, you might think the quality of your water is an obvious and easy consideration when brewing your beer. You aren’t going to use pond water to brew your beer because then your beer would taste like pond water! Well this is true, it’s a no-brainer that you are going to use water that is clean and safe to drink, but it goes much deeper than this (no pun intended). Tap water may seem like a safe bet; you drink it every day and it tastes fine. For many people this is true, but you also have to consider the chemistry of that water.
The makeup of the water used to brew will be important to the all-grain brewer and the extract brewer for very different reasons. I’ll get the easy part out of the way first by saying that water chemistry is of much less concern to the extract brewer. If you don’t notice any off flavors in your water when you drink it from the tap, then you should be fine to use this for all of your extract brewing needs (unless you are doing a partial mash recipe with specialty grains, but I will elaborate on this in my future post on the partial mash process).
However, if you do have some strange tasting tap water, you might want to try to reduce the flavor by filtering the water, installing a water softener, or just using bottled water. When I started brewing, I didn’t even want to mess with water chemistry so I bought bottled water for my brews. This was fine for 2 gallon batches (although it was kind of a hassle), but for 5 gallon batches I decided it was time to learn about my tap water. Most tap water suppliers will provide a water quality report that is easy to access online, but you can also just give your local water department a call if you have trouble finding this.
I later learned that the makeup of my water is really just important for all-grain brewing for one big reason: mash pH. Now that sounds really scientific and confusing, but it doesn’t have to be! There are some easy ways to estimate how your water will fair when mashing your grains, and a lot of homebrew stores sell pH paper that will tell you how well you guessed. If you’re just a beginner, you can still make a really good beer as long as you’re close (and like most things, you will get better with practice).
You may be surprised to find out just how many of the constituents that you will find on your water report will have some sort of effect on the taste of your beer (some will have a large effect and others will be arguably negligible). I’m going to refer you to John Palmer’s book How To Brew if you want to know all of the nitty gritty details, but I will give you an overview of the important things to look for: magnesium (Mg), calcium (Ca), and alkalinity (in the form of carbonate, CO3, and bicarbonate, HCO3).
These three components in your water determine how “hard” your water is, and the level of hardness required will differ depending on the style of beer you’re making. Darker grains are more acidic and these will drop the mash pH more than a grain bill full of lighter grains will. Palmer provides a really good example in his book when he mentions two regions of Europe known for beers that are very much opposites. The beers I’m referring to are the classic Irish Stout and the timeless Czech Pilsner. I love this example because I lived in the Czech Republic for four months (where I sampled many fantastic pilsners), and I also got to visit the Guinness brewery while abroad. Plus my wife comes from a very Irish family, so you better believe we drink Guinness in our household! Needless to say, I love both of these styles of beer dearly.
This is the perfect example because these two beers are on complete opposite extremes of the color scale, and color is an important consideration when planning your mash. Dark beers will require roasted grains that will have a more significant effect on lowering your mash pH, and this is why the naturally hard water of Ireland is perfect for brewing Guinness! Beers that are light in color will not include these dark-roasted grains in the grain bill, so the pH drop from the grains is not as extreme. This is why the soft and pure water found in the Czech Republic is perfect for brewing Pilsner Urquell!
Now you can pick just about any beer and it will fall between Guiness and Pilsner Urquell on the color scale. All you have to do is decide what style of beer you want to make! Palmer recommends a pH of about 5.4 to 5.8 for your mash, and he provides a really good nomograph for determining how your water will do when used for mashing various styles of beer. If the makeup of your water doesn’t work well for your chosen style of beer, then don’t panic. If needed, you can make your water “softer” by diluting it with distilled water or by just using store bought water (you may want to contact the manufacturer for the makeup of the water you purchase). If your water is too hard, you can add a number of things including sodium bicarbonate (a.k.a baking soda) or calcium carbonate (a.k.a chalk).
Now who would have thought that the water you use for your brewing would be so complicated. Well, beer is over 90 percent water, so I guess it makes sense! If you have any helpful tips for how you deal with the water in your area, or if you have any additional question, please leave a comment below! For those of you just starting out please don’t be intimidated by all of the complicated language. I recommend you just go for it and give it your best shot! I can’t wait to hear how it goes! Cheers!