Water

The following minerals found naturally in water are the ones we adjust in brewing:

· Calcium (Ca): Essentially flavour neutral. Promotes clarity and flavour stability of the final beer. Affects enzymatic activity in the mash, protein coagulation during the boil and benefits yeast health. Typical brewing range is 50-150 ppm.

· Magnesium (Mg): Adds a sour, astringent flavour. An important yeast nutrient, required at a level of least 5 ppm. Levels above 125 ppm have a laxative effect (fun times).Typical brewing range is 5-40 ppm.

· Sodium (Na): Rounds out flavours and accentuates sweetness. Lower concentration tends to produce a cleaner flavour. May taste salty above 150 ppm and harsh / sour above 250 ppm. Typical brewing range is 0-50 ppm, but some special styles (like Gose) may go as high as 250 ppm.

· Chloride (Cl): Accentuates flavour by making a beer fuller bodied, rounder, and to appear sweeter. May taste salty above 250 ppm and will affect yeast health above 300 ppm. Typical brewing range is 0-250 ppm.

· Sulfate (SO4): Accentuates hop bitterness / dryness / crispness. May become astringent above 400 ppm. Typical brewing range is 50-350 ppm.

Adding these minerals to our brewing water is unfortunately not as simple as buying a bottle of each and adding a pinch of this and a dash of that. Through the wonders of nature (we promised no chemistry here!) many of these minerals cannot safely exist on their own, in a stable form. Pure sodium (Na), for example, is a toxic metal that explodes if it comes in contact with water which would make for a very bad brew day. But combine sodium (Na) with chloride (Cl) and we create a stable salt, in this case regular table salt (NaCl). So when we add minerals to our water, we're usually forced to do so two at a time using readily available and stable salts. Adding salts also happens to affect pH, but more on that later.

The salts we use to adjust the mineral content of our water are as follows:

Gypsum / Calcium sulfate (CaSO4): Adds Ca and SO4, lowers pH.

Calcium chloride (CaCl2): Adds Ca and Cl, lowers pH.

Pure epsom salt / magnesium sulfate (MgSO4), unscented: Adds Mg and SO4, lowers pH (very slightly).

Chalk / Calcium carbonate (CaCO3): Adds Ca, raises pH.

Baking soda (NaHCO3): Adds Na, raises pH.

Non-iodized salt (NaCl), also known as pickling salt / kosher salt / cheese salt: Adds Na and Cl, raises pH.

Out of these six salts, the first three are the ones we use the most. We will sometimes use chalk with dark beers where we want to increase Ca without affecting other minerals. We have yet to use baking soda or non-iodized salt after many years of brewing.

My water report has sulfate as SO4-S instead of SO4. Is that the same thing?

Nope. You probably received a water report from Ward Labs who reports sulfate as SO4-S instead of of SO4. To convert to SO4 you need to multiply by 3. For example, if your water report indicates that you have 6 ppm of SO4-S, you have 18 ppm of SO4.

What about alkalinity / residual alkalinity? I read that it was really important in brewing!

The short answer: Ignore it. While it's important, we don't deal with it directly when adjusting water to target specific flavour profiles.

The long answer: Alkalinity refers to how effectively water is able to resist a change in pH, in other words, how well it is able to neutralize or 'buffer' acids before the pH changes. The higher the alkalinity or 'buffering capacity' of the water, the more acids or salts we need to add to lower the pH in order to achieve a proper mash pH. Most city water has a pH of 7.0 or higher but the pH range we want for our mash and finished beer is considerably lower. Hard water (water full of minerals such as Ca and Mg) is highly alkaline.

Bru'n Water Reddit talk

A: Bru'n Water consistently predicts lower pH for pale beers than real life

B: It’s been pretty much spot on for me across styles. I scale up from our 10gal pilot to 20bbl batches using it and it’s nearly linear. Usually just a minor adjustment.

We add our chemicals at the beginning of mash in fwiw

A: When mash-in was taking 30 minutes for 20bbl+ it seemed natural to add the chems in increments, but I can see why adding it all in the beginning also makes sense. I will give this a go for the next brew.

C: Did you notice a difference doing this? We do the same as yourself, incrementally thinking that it spreads them through the process evenly

A: Yes. Adding them all up front got me within 0.05pH of target.

C: Are you able to elaborate on why this is the case please?

D: With Bru'nWater, you're making the water before you brew with it. This is not like cooking where you are seasoning at every point along the way. There are pH buffering effects which will not be realized if you don't add all the salts and acid to the water up front as calculated, ideally before it even touches your malt.