For brewers who want to start treating their water appropriately, but don’t want to wade through the requisite chemistry, here’s the third in my series of simple water guides. Today’s post is a quick guide to generating brewing liquor for brown beers, from 20 to 30 SRM. This includes brown ales, some porters, many dark lagers, etc. You begin with 5.0 gallons (19 L) of distilled water and add minerals to create your brewing liquor.
I will post the remaining guide — for pale beers (0–10 SRM) — soon.
Dark Grains and Acidity
Specialty malts are darker than base malts and also more acidic. However, the darkest roasted grains are not proportionally more acidic than crystal malts and don’t get more acidic with increasing color. So, in order to estimate the level of acidity your darkest grains are adding to the beer, you need to do one of two things. In your recipe software, either replace any darkly roasted grain in your recipe with a dark crystal malt (crystal 120 °L, for example) or change the color rating of your darkly roasted grains to around 120 °L. Note the SRM the brewing software calculates for this, then return the recipe to it’s correct formulation. Use the revised SRM to formulate your brewing liquor. (See the post on brewing liquor for dark beers for more on this.)
Here is a guide to making 5.0 gallons (19 L) of brewing liquor for a brown beer, starting with 5.0 gallons (19 L) of distilled water. If you are a 5.0 gallon (19-L) extract brewer, you only need to make half this volume. Halve the volumes of water and the amounts of minerals added. Use the treated water (the brewing liquor) for steeping your grains or doing a partial mash and for the water in the boil. Use distilled water for topping up to your full batch size. All-grain brewers will need to estimate how much water they will need and mix up sufficient brewing liquor.
Your first step is always to ensure that your brewing liquor has sufficient calcium. Calcium has a number of benefits in the mash and in the boil. I like to start with around 100 ppm (roughly 100 mg/L) of calcium in my brewing liquor. So, no matter what your estimated beer color is, start by adding calcium to your 5.0 gallons (19 L) of distilled water. If you are brewing a beer with a nice malt and hop balance, add 1 tsp. (roughly 4 g) of gypsum (CaSO4) and 1 tsp. (roughly 3.4 g) of calcium chloride (CaCl2). If you are brewing a hoppy beer, such as hoppy brown ale, add 2 tsp. (roughly 8 g) of gypsum and no calcium chloride. In both cases, this will give you roughly 100 ppm calcium. In the case of the hoppy beer brewing liquor, you will also have 200 ppm sulfate in the water, which should accentuate the beer’s hop bitterness nicely.
The second, and final, step is to add an amount of carbonates to the water that is appropriate to counter the acidity of the dark grains. Use your revised SRM and follow these instructions (or the instructions for an amber beer, if the revised SRM falls in that range). For a beer near 20 SRM, add 1.25 tsp. (roughly 5.5 g) of baking soda (NaHCO3). For a beer near 30 SRM, add 1.75 tsp. (roughly 7.7 g) of baking soda (NaHCO3). For beers between 20 and 30 SRM, add an intermediate amount. For example, 1.6 tsp. (6.8 g) of baking soda (NaHCO3) in 5.0 gallons (19 L) of distilled water is the right amount for beers that are estimated to be around 25 SRM (again, using the revised SRM estimate).
You should taste the distilled water before treating it, and after the minerals are dissolved. At first, it shouldn’t taste like anything. With the minerals added, it should taste pleasant (as you would expect mineral water to taste). If you are an all-grain brewer, you should take the pH of your mash — and it should fall within the 5.2–5.6 range, with the lower half of this range being preferable. Keep in mind that the mash pH might change early in the mash and you may have to wait for it to settle into a stable reading.
During the boil, you should look for the presence of hot break. It should look like like big, fluffy “snowflakes” floating in otherwise clear wort. If your wort looks muddy or each piece of break material is just a small speck, add another 50 ppm of calcium to the boil. For 5.0 gallons (19 L) of wort, this is 1 tsp. of either gypsum or calcium chloride, or a blend of the two.
If you’re using brewing liquor made from distilled water, adding a dose of complete yeast nutrients to the boil may be a good idea to ensure that any trace elements the yeast may need are present.
And finally, you should taste your beer critically. If you have brewed brown beers before, treating your brewing liquor should improve their flavor. If it didn’t, your local water is likely suitable for brewing beers in this color range and there is no reason to go to the extra hassle.