By Greig McGill
So ya wanna adjust some water, eh kiddo? Well lemme tell you… no seriously, here’s my design process for my brewing liquor - the fancy professional term we almost never use in the brewhouse! I’m assuming you’ve read the previous blog post, and have chosen a water calculator or piece of brewing software if you want to work along with me. I’m not going to go through the specifics of how to use those, but there’s almost certainly a video on YouTube for that!Tomorrow, I’m brewing our APA - The Formfiller. It’s called that because it checks a box in my soul - the need for a classic, old-school pale ale, like they used to be when your choices of hop flavour and aroma in the USA were limited to citrus - usually pink grapefruit - and/or pine resin. Yep, the classic old C-hops of Cascade, and later, Centennial. The Formfiller is a tribute to Sierra Nevada Pale Ale - one of the first US beers I ever tasted, and still something I try to have fresh on every trip over to the star-spangled nation.
As I type this, I’m reviewing my water choices. First, I need to know what my grist and my base water profile look like. It’s a simple grist - 250kg of malt, with 90% being Gladfield American Ale, and the remaining 10% being Gladfield Vienna. This divides nicely into 9 sacks of American Ale, and one of Vienna, but that couldn’t possibly have anything to do with the design choice, right? Ahem. Moving on. My water, according to our most recent water report for Te Rapa has an alkalinity of 24ppm as CaCO3 and a residual alkalinity of 34ppm as CaCO3. That’s good. Anything under 50 for RA is pretty great to brew with because of the low “push back” or buffering factor. It means that water pH adjustments are easy to make without going crazy on the minerals or the acid and thus unbalancing my beer’s intended flavour profile.
For reference, my water also has 11.7ppm of calcium, 2.5ppm of magnesium, 17.2ppm of sodium, 21ppm of sulphates, 14.2ppm of chlorides, and 41.48ppm of bicarbonate. This gives a natural sulphate:chloride ratio of 1.5:1, which is good for balanced beers teetering very slightly on the hoppy side. We’re going to mess with that a little!
If you’ve ever had fresh Sierra Nevada Pale Ale, the bitterness can be quite striking! So the first thing I’m going to do is target a nice sulphate:chloride ratio of around 3.6:1. I’m also going to get a little more magnesium in there for yeast health, and a little chloride to round out the mouthfeel - I don’t want it too “flinty”. I’m using calcium sulphate (gypsum), calcium chloride, and magnesium sulphate for my mineral additions, and am targeting 120ppm of calcium, 14ppm of magnesium, 247ppm of sulphate (yes, that’s high, I like it), and 70ppm of chloride. All that calcium means my pH will be quite high, so I’ll need a decent acid addition to overcome the residual alkalinity and lower my mash pH to my target of 5.4. I use Lactic Acid at 80% concentration. Notice, I’m not giving you amounts of minerals or acid - it would be meaningless, as your water and volumes will mean you’ll need to calculate for yourself. Suffice it to say, you’ll want your mineral numbers to be close to the above (to within a few ppm is fine) and then use an acid addition calculator to achieve the target pH.
I usually hit my pH on the nose, and if I don’t, it means I’ve either added too much or too little water, or (rarely) my input water has changed enough to throw my calculations out, and it’s time to pay the lab again! Of course, there’s also the rare scenario where my ex-lab technician wife has forgotten to calibrate the pH meter, but I’m annoying enough to live with without blaming her for my failings!
Once in the kettle, and boil is underway, I’ll usually take another pH reading and then add enough lactic acid to get my kettle pH to around 4.9. This promotes excellent hot break and clarity. Needless to say, I’ll skip this step if I’m making a hazy beer.
OK, how about another example? Shorter this time, since the basics are the same and I’ve already listed the water profile. Let’s try a nice English bitter. These, despite the name, are known for balance and quaffability, so we’re not going to tweak the water too much. We’re going to add a little “roundness” with some sodium chloride, and use the same three minerals as in the previous example (calcium sulphate (gypsum), calcium chloride, and magnesium sulphate). We’re going to target 80ppm of calcium, 14ppm of magnesium, 45ppm of sodium, 120ppm of sulphate, and 100ppm of chloride. This gives us a nice balanced 1.2:1 sulphate:chloride ratio. As we’re using less calcium, we’ll also need less acid to adjust - helped along by the fact that I often use some darker malts in my English grists for richness and complexity. In fact, with my grist, I require no acid addition at all for a mash pH of 5.25, and then I adjust in the kettle as before to 4.9 pH.
So, there’s my thinking and process for two beers. Where did I get these numbers for mineral counts? Why are they “the best”? They’re not, and they’re certainly not gospel. They reflect my particular brewing philosophy and my own tastes based on beers I’ve enjoyed over the years. I’d strongly advise you all to avoid “charts of numbers” on the internet, and instead, think about what each mineral “does” in the beer, and how much of that character you want. All the while, being mindful of pH. Sometimes, less is more. For example, the common wisdom says to use a ridiculous amount of chlorides in a hazy IPA, but I find it makes them lose definition and taste chalky and unappealing, often enhancing hop burn. That’s my opinion, it’s not a fact. Taste, read, think, and then come up with your own target mineral profiles for water adjustment. Try it - is it good? If not, iterate and adjust until it is.
Remember that, as I said in the last blog post, there have been entire books written on this topic. Water adjustment is an extremely complex subject to understand fully - few brewers, perhaps none, truly do given how much is still being researched. That said, knowing the basics and being mindful of what you are doing rather than just following a process because someone said so is always a good way to succeed.
Happy brewing, and save me a pint!