A Simple Worked Approach to Water Treatment

James Wilson gave a talk on his approach to water treatment at the September, 2018 LAB meeting.

Transcript

1. A Simple Worked Approach to Water Treatment James Wilson London Amateur Brewers 3rd September 2018
2. Let’s talk about water Water treatment is simpler than it seems… …But it is a more advanced area for brewing o Unless you are brewing consistently good beer there is little need to change your water – work on fermentation/yeast first. o Like seasoning food it won’t make bad beer good, but it can make good beer great!
3. We’ll cover my approach Work with your own tap water: 1. Remove Chlorine to avoid off flavours 2. Reduce Alkalinity to get mash pH in the right area 3. Adjust final ion balance in the finished beer to achieve the dryness/fullness. Should work for most people around London and Home Counties, and often further too. Reverse Osmosis or low ion content bottled water are quite different approaches, but I’ll touch on them.
4. What’s in water? Ion Affects Recommended levels Calcium Alkalinity At least 40ppm to help mash and clarity Magnesium Alkalinity and Flavour 0 - 40ppm - more can have a sour flavour. Sodium Flavour Ideal 0 - 50ppm, but can go to 100ppm. Chloride Flavour 0 - 250ppm – balance with Sulphate Sulphate Flavour 0 - 350ppm – balance with Chloride Bicarbonate Alkalinity Whatever you need for mash pH Chlorine Can create off flavour Zero …also Nitrate, Potassium, Phosphate and many other things which shouldn’t have an effect on your beer at levels found in tap water
5. Let’s look at Bermondsey No Calcium or Bicarbonate – that’s fine, we’ll work it out later
6. But what’s in MY water? o Water report from Murphy and Son (also sold via Brew UK https://www.brewuk.co.uk/water-analysis.html) or Phoenix Analytical (http://www.phoenix-analytical.co.uk/) o Water quality report from supplier o You want to know Sodium, Magnesium, Chloride and Sulphate. o Only Chloride and Sulphate are essential o Sodium/Magnesium is more to check they’re not at high levels o Lots of tests so you can see variation o Use an Alkalinity test kit to understand the level of Carbonate/Bicarbonate in water o Note: In any report the values can change due to changing water supply
7. Step 1: Remove Chlorine o Why? Chlorine will bind to phenols in the mash to create chlorophenol, a medicinal off flavour o How: For up to 40 litres crush half a Campden Tablet (sodium metabisulphite) and add to your total brewing water. o A single 0.5g tablet will remove up to 231ppm Chlorine o In our example, Bermondsey report says 0.75ppm max, so a single tablet could treat up to 300 litres o Sodium or potassium metabisulphite are also available in powder form o Chlorine is odourless, what you can smell in water is Chloramine (Chlorine + Ammonia) but is treated the same.
8. Step 2: Reduce Alkalinity… What’s ‘Alkalinity’? o Wait… what’s ‘alkalinity’ is it like ‘hardness’? o Water hardness and alkalinity are different things, although their levels often move up and down together. o Hardness is a measure of Calcium and Magnesium in water o It is really a measure of how difficult it is to lather soap… o Alkalinity is the level of Carbonate (CO3 ) or Bicarbonate (HCO3 ) in the water o Confusingly they’re often both measured as CaCO3 o They change together because our water is usually filtered through chalk and other minerals: o H2 O (l) + CO2 (aq) + CaCO3 (s) -> Ca2+ (aq) + 2HCO3 − (aq) o (Water with Carbon Dioxide in solution filtered through chalk reacts to create Calcium and Bicarbonate in solution)
9. Step 2: Reduce Alkalinity… Why? o Alkalinity buffers against pH change in the mash o Water will be around pH 7 o Malt grist has buffering power to lower pH o Darker grains have more power o We want the mash to fall to 5.2-5.6* for optimal enzyme activity and finished beer pH o Too much alkalinity for a pale mash will not allow the pH to drop enough o Not enough alkalinity for a dark mash will cause it to drop too far *measured at room temperature
10. Step 2: Reduce Alkalinity… Why? o Aiming to adjust mash liquor to the following range: o Pale beer – 30ppm as CaCO3 o Brown beer – 50-80ppm as CaCO3 o Dark beer – 80-150ppm o Sparge liquor: o 30ppm if you fly sparge to stop pH rising o For batch sparge treat as per mash or not at all
11. Step 2: Reduce Alkalinity – How? o First you measure your alkalinity! o Salifert Carbonate Hardness/Alkalinity test kit, about £9 for 100+ tests o Convert result in meq/l to ppm by multiplying by 50
12. Step 2: Reduce Alkalinity – How? o Recommended: Reduce to range using a food grade acid o CRS/AMS – blend of Hydrochloric and Sulphuric acids o Phosphoric acid o Dilution with Reverse Osmosis o Caution: Lactic acid – has a low ‘infected’ taste threshold, so be careful o Caution: Water softeners o Cheap ones exchange sodium for calcium – don’t use this! o Expensive are Reverse Osmosis, but need maintenance o Caution: Acid malt o Malt that has lactobacillus grown on it to create lactic acid o Created o get around German beer purity law (reinheitsgebot) o Effectively the same as using lactic acid
13. Step 2: Reduce Alkalinity – My way o Reduce to range using CRS/AMS or other acid o CRS/AMS is a blend of food grade Hydrochloric and Sulphuric acids. Easy to get hold of from brewing suppliers. o 1ml of CRS/AMS in 1 litre of water will: o Reduce Alkalinity by 183ppm o Increase Chloride 64ppm o Increase Sulphate by 89ppm
14. Step 2: Reduce Alkalinity (Pale Example) o Brew length 23 litres with 5kg grain o Bermondsey Water = 217ppm CaCO3 o Target of 30ppm alkalinity for mash o 30ppm for sparge o Calculate CRS required: (217-30) / 183 = 1.02 ml/l o Result: o 12.5 litres mash liquor treat with 12.8ml CRS o 18.5 litres sparge liquor treat with 18.9ml CRS o Or just treat all 31 litres with 32ml CRS
15. Step 2: Reduce Alkalinity (Dark Example) o Brew length 23 litres with 5kg grain o Bermondsey Water = 217ppm CaCO3 o Target of 100ppm alkalinity for mash o 30ppm for sparge o Calculate CRS required: (217-100) / 183 = 0.64 ml/l o Result: o 12.5 litres mash liquor treat with 8ml CRS o 18.5 litres sparge liquor treat with 18.9ml CRS
16. How do I know I got it right? o Measure pH 10 minutes into mash o A pH meter is a good investment o I recommend the Voltcraft pH-100 (about £65) o You will need calibration buffers too o Spray pH probe with deionised water and pat dry between calibrations/readings o Narrow range pH strips are very difficult to read o Cool a sample to room temperature before measuring
17. Step 3: Adjust Final Ion Balance o Why? The final touch. Helps adjust your beer to either be ‘dryer’ or ‘fuller’ depending upon what you want and boosts calcium levels if required. o Sulphate : Chloride ratio in the finished beer has an effect on the final mouthfeel of the beer: o Most beers will benefit from a slight Sulphate balance (1.5:1) o Pale ales, IPAs and bitters can go more (3:1) o Stouts and more recently New England IPAs will benefit from the fullness of a Chloride balance (1:2 or 1:3)
18. Step 3: Adjust Final Ion Balance o How? Add Calcium Sulphate (Gypsum) or Calcium Chloride to the boil o What you add depends upon what you have already in the liquor and your CRS addition o Work on the final volume in the beer o If you have less than 100ppm Calcium you can add half to the mash o Approximate Calcium with 0.4 x Alkalinity value (e.g. Bermondsey 217ppm = 87ppm Calcium)
19. Step 3: Adjust Final Ion Balance 1 gram in 1 litre of Calcium added Other Added Calcium Sulphate (Gypsum) 232 mg 558 mg Sulphate Calcium Chloride 272 mg 483 mg Chloride Magnesium Sulphate (Epsom) 0 98 mg Magnesium 390 mg Sulphate Sodium Chloride (Table Salt) 0 393 mg Sodium 606 mg Chloride
20. Step 3: Adjust Final Ion Balance (Pale Example) Step Working Volum e Litres Alkalinity ppm (as CaCO3) Calcium ppm (Alk x 0.4) Sulphate ppm Chloride ppm 1. Starting water 217 87 48 43 2. Reduce alkalinity All liquor + 32ml CRS 31 30 87 139 109 3. Post Mash Volume reduced due to grain absorption* 26 N/A 139 109 4. Post Boil Liquor concentrated by boil off of 3 litres 23 N/A 98 157 123 *Grain absorption = 1L/kg
21. Step 3: Adjust Final Ion Balance (Pale Example continued) Step Working Volume Litres Calcium ppm (Alk x 0.4) Sulphate ppm Chloride ppm 4. Post Boil Liquor concentrated by boil off of 3 litres 23 98 157 123 • Sulphate to Chloride ratio is 1.27:1 (157:123) • Pretty good, but let’s aim for 300ppm Sulphate for a ratio of 2.4:1 • 1g Gypsum in 1 litre adds 232pm Calcium and 558ppm Sulphate • We want to add 143ppm (300-157) • 143 x 23 litres at end of boil = 3289ppm • 3289 / 558 = 5.89g of Gypsum 4. Post Boil w Gypsum 5.9g Gypsum added 50:50 to mash and boil 23 159 300 123
22. Step 3: Adjust Final Balance (Dark Example) Step Working Volume Litres Alkalinity ppm (as CaCO3) Calcium ppm (Alk x 0.4) Sulphate ppm Chloride ppm 1. Starting water 217 87 48 43 2. Reduce alkalinity Mash liquor + 8ml CRS 12.5 100 87 105 84 Sparge liquor + 18.9ml CRS 18.5 30 87 139 109 3. Post Mash Combined liquors in proportion, volume reduced due to grain absorption* 26 N/A 87 125 99 4. Post Boil Liquor concentrated by boil off of 3 litres 23 N/A 98 142 111 *Grain absorption = 1L/kg
23. Step 3: Adjust Final Balance (Dark continued) Step Working Volume Litres Calcium ppm (Alk x 0.4) Sulphate ppm Chloride ppm 4. Post Boil Liquor concentrated by boil off of 3 litres 23 98 142 111 • Sulphate to Chloride ratio is currently 1.28:1 (142:111) • Let’s do balance instead in favour of Chloride – get to 250ppm (1:1.76) • 1g Calcium Chloride in 1 litre adds 272pm Calcium and 483ppm Chloride • We want to add 139ppm (250-111) • 139 x 23 litres at end of boil = 3197 ppm • 3197 / 483 = 6.6g of Calcium Chloride 4. Post Boil w Calcium Chloride 6.6g CaCl added 50:50 to mash and boil 23 176 142 250
24. The Approach Again: 1. Use half a Campden tablet to remove chlorine 2. Reduce Alkalinity to between 30-120ppm with CRS 3. Add some Gypsum / Calcium Chloride in the boil (and possibly the mash)
25. A Word on Water Calculators… o How do I use Bru’n Water/JBK/Beersmith water calculator? o I don’t any more o They have to contend with many scenarios and approaches making them very complex o A bit too precise o Still need to measure mash pH o I’ll be publishing a spreadsheet that does the calculations in this presentation for you soon… o Why not use RO and build what you want? o You can do that, but you don’t need to in most cases
26. If you want to know more o London Amateur Brewers: https://londonamateurbrewers.co.uk/2014/03/water-treatment/ o Bru'n Water knowledge page: https://sites.google.com/site/brunwater/water-knowledge o The Brewing Forum: http://forum.craftbrewing.org.uk/viewtopic.php?t=907