Why pH Matters in Brewing
When we talk brewing chemistry, pH control sits right at the top of the priorities list. Why? Because 95% of beer is water! If your process water isn’t treated with the correct dosage rates, nothing else will be quite right. Get your pH spot-on and you’ll see faster wort separation, higher extract yields, quicker fermentation, and better attenuation. But get it wrong, and you’re in for poor extract, finings headaches, stuck fermentations, weak head retention, and even microbiological issues.
The Role of Liquor Treatments
The main goal of liquor treatments is simple: turn your tap water into first-class brewing liquor. But you can’t treat what you don’t know! Water must be analysed before you can determine the right liquor treatment. And because water authorities often mix sources to meet demand, your water’s ionic makeup can change throughout the year, even within the same region.
Testing and Analysis: Your First Step
To stay ahead, send 100ml of your raw liquor to Murphy’s laboratory for a full analysis and recommended treatment rates. Local authority reports may not always be up to date, so it’s wise to do your own testing at least twice a year, or more often if your supply changes.
Prefer DIY? Alkalinity testing kits are available from Murphy’s for hands-on brewers.
Which Ions Matter Most?
In water analysis, we focus on alkalinity, calcium, chloride, and sulphate. Chloride boosts fullness and sweetness, while sulphate sharpens bitterness. But for the mash, calcium is king, helping prevent beerstone, increasing yeast flocculation, improving head retention, and aiding protein precipitation during the boil.
Calcium & pH: The Dynamic Duo
Calcium ions combine with phosphate in the mash, forming calcium phosphate and releasing hydrogen ions, which lower the pH. That’s why understanding and controlling calcium levels is so critical.
How to Assess and Adjust Alkalinity
Start with your raw liquor’s temporary hardness (alkalinity), measured in ppm as Calcium Carbonate. Alkalinity is the amount of acid needed to lower pH to a specific value (4.3, in this case).
For bitters: Aim for alkalinity of 30-50 ppm. If it’s higher, add acids like AMS, Sulphuric Acid, Hydrochloric Acid, or Phosphoric Acid. If it’s lower than 30 ppm, add calcium carbonate.
Once the acid dosage is set, you can calculate the calcium addition. For bitters, shoot for 180-220 ppm calcium. If you’re low, add salts such as Calcium Chloride, Calcium Sulphate, or DWB. Remember, ideal ion levels vary by beer style.
Best Practices for Liquor Treatments
All treatments must be food grade. Add acids to the HLT and dose for all process water; mix powders evenly in the grist according to your batch size. Never add acids and salts at the same time, this could block your pipes! Keep records of your liquor, wort, and beer pH throughout the process to help you stay on track.
Choosing and Using a pH Meter
If you don’t have a pH meter yet, now’s the time. Benchtop pH meters are ideal, but handhelds work too, Murphy’s stocks the Myron PT2. For best results, calibrate your meter every time you use it with fresh pH 4 and pH 7 buffers, and store the probe in proper solution. Out-of-date buffers and uncalibrated meters lead to inaccurate readings.
Optimum pH: What the Experts Say
Brewing scientists have their opinions, but here’s what they suggest:
- Charlie Bamforth (Sierra Nevada): pH 5.6-6.1 maximizes extract; 5.0-5.5 maximises soluble nitrogen. Most mashes: 5.3-5.58.
- Kunze & Narziß (German brewing experts): 5.5 is best for starch conversion; 5.2-5.4 is ideal for flavour and stability.
- DeLange (homebrewing water guru): “The biggest single improvement in my brewing came when I started actively controlling pH to 5.3–5.4.”
For cask-conditioned beers, aim for 5.0–5.3 boiled wort pH. Expect pH to fall by 0.05–0.15 units during boiling, and further during fermentation.
The Final pH Frontier
Your finished beer should have a pH of 3.7–4.2 for the best flavour, mouthfeel, stability, clarity, and head retention. Supplying enough calcium supports enzymatic activity and helps you hit your downstream pH targets.
Need a Hand?
If all this sounds too technical, let Murphy’s do the work! Send us your water sample and we’ll test, calculate acid and salt additions for your beer styles, and provide you with all the guidance you need. All you have to do is monitor your pH and adjust as needed.
Brew confidently—because great beer begins with great water and precise pH control!