I don't do much water treatment, but have been studying the topic in some detail as I am curious as to whether it is worth it for me. I am an All Grain brewer with some 9 years AG experience and the most I do is pre-boil my water prior to mashing.
Some of the above threads that compare what commercial brewers do to their water are interesting, but hardly relevant to the home brewing sphere in general I think. Yes, most commercial brewers treat their water and yes it is mostly for consistency and mash efficiency (the bean counters win again). But is the time and money spent in adding minerals (ie Calcium Sulphate CaSO3 {aka Gypsum}) to reduce the affects of other minerals (ie - Calcium carbonate CaCO3 {aka Chalk}) as well as the boiling and transfering of water from the resultant deposits really worth it?
So when should we treat our water in the AG environment;
(a) If it's to emulate a beer style or clone a commercial beer , then we may want to treat our water to emulate theirs for Mash pH reasons right? However, as has been pointed out above by
Mabrungard and
Sterzir, Guinness likely use soft water (not what we have all be led to believe by Palmer and others) which they treat anyway. So what is the make up of the water Guiness and other commercial brewers use???
Gosling said:
The only thing I can find in Palmers text is "The fact of the matter is that dark beer cannot be brewed in Pilsen, and light lagers can't be brewed in Dublin without adding the proper type and amount of buffering salts".
I find statements such as this as questionable, as not only do Guinness likely use soft water, but there are many historical and current Czech and German black lagers (Schwarzbier) from areas with similar water profiles as Plzen and they are not sour or acidic as Palmers statement would suggest. Maybe some of the mashing techniques they developed over the centuries (acidification rests, use of appropriate malts) should be paid close attention to as they worked prior to knowledge of water chemistry.
Back to the modern worlk, we should probably all be looking at what our water make up is and what the main effects are on the pH of the mash as the original question seems to show some confusion about where the pH is important. After all, knowledge is power. Back to the original question;
Gosling said:
What I dont get is why I cant make a decent pale beer with hard water or a decent dark beer with soft water, nor why the pH of the mash is important to the style. All I understand is that the correct pH is required for a decent starch conversion at the target mash temperature.
The way i see it is that if I have a water with high alkalinity I could theoretically reduce pH with lactic acid and not additional minerals and hit the target pH for a pale beer as per the Palmer nomograph. If so why would the beer taste bad ?
Gosling, to answer your question I am going to quote from Graham Wheeler (p.52 Brew Classic European Beers at Home, Wheeler & Protz, CAMRA Ltd 2001)
"One of the biggest myths, that dark beers prefer carbonate water and pale beers prefer gypseous water, simply is not true. What is true, from the scientific perspective at least, is that carbonates are detrimental to beer and sulphates are beneficial, but they are theoretical benefits, mostly only of importance to commercial brewers. In practice it does not seem to make a ha'porth of difference to the majority of home brewed beers, from the flavour perspective, whether the water is treated or not." Wheeler goes on to say that he is sceptical that cloning commercial brewers water mineral make up will assist the home brewer, as the commercial brewers change their water make up to bring their mash pH to the theoretical optimum of 5.3 (or at least below 5.6) (Wheeler & Protz 2001).
Also, you should just about forget the actual pH of your water unless it is extreme (over 8.5 or under 5.5 which aren't relevant in most municipal water supplies in Australia). Wheeler states
"Do not fall into the trap and think that the pH of your brewing water and the pH of the resultant mash are equivalent - they are not" (p.53 Wheeler & Protz 2001). The importance of water treatment is all about the influence of the buffering mineral ions (ie calcium carbonate) on the various ions in the grains and how they interact to create an environment that is optimal for sarrification enzymes (iAlpha-amylase and Beta-amylase). One should aim to have the mash pH (
not strike water pH) between 5.2 and 5.6 for the enzymes to work at at their optimum.
(b) Secondly we may want to treat our water if we are noticing bad efficiency (anything less than 55% could be improved) in the mash or more importantly, strong astringent flavour profiles that are undesirable. The reason taste as opposed to efficiency is the biggest issue is two fold. Apart from mash pH your efficiency could depend a lot on your lautering technique, so you could be stuffing around trying to change your water mineral profile, when the real problem lies elsewhere. It is when the flavour is effected that we home brewers should be taking action and we should test the pH of our mashes to see where we can change things to improve beer taste (and to a lesser extent efficiency, as grain is cheap lets face it). I live in Adelaide (reputedly the hardest municipal water in Aust.) and our average hardness (Calcium carbonate) in 2013 was 123 mg/L (considered hard water, but acceptable as it is less than 200 mg/L) and in 2014 it was averaged at 90 mg/L (Melbournes highest is 60mg/L and the average for many suburbs is around 20 mg/L).
Now when we think about it, water is a medium that allows the ions in the grain to react with the ions in water (and it's minerals) and the quantity of buffering "akaline" ions (ie Calcium carbonate) effects how the grain pH in the mash changes when the grains react with the water (and how much acid is produced). It has very little to do with the pH of the original water and everything to do with how the dry grain acidifies when it reacts with the water. The make up of the minerals in
both the water and the grain have a big effect on that reaction. So, it is easier for
pale malt grain mashes to reach optimal pH range of 5.2-5.6 when the minerals in the water aren't stopping acidification (lowering of pH). When the water contains more carbonate minerals (ie harder, like Adelaide) minerals like calcium carbonate buffer the acidification ions making pale malt mashes less acidic.
Now both soft and hard waters could have the same pH, but the effect on the mash pH is completely different. Because darker malt is more acidic than pale malt it counteracts this mineral pH buffering and the optimal pH range is easier met in harder water. Within the optimal pH range, extraction of astringent characters from the grain husks is also reduced so improving flavour (as well as efficiency so it's a double win). So, if you have soft water (ie melbourne) and want to use a lot of black malt, roasted barley or other dark grains then you should consider adding anywhere between 4 gm (London) to 13 gm (Burton) of calcium carbonate to 30 Litres (I got this from Vicbrew Brewing Almanac 2002) and maybe some calcium sulphate (gypsium) too (3 gm for Dublin or Yorkshire and 18 gm for Burton!). This will reduce the chance of strong astringent flavours being drawn from the grain and create a better tasting more rounded Porter, stout etc...
My suggestion for harder water areas (ie Adelaide) though is don't treat your water. We have a good mineral hardness profile for dark beers and if you want to improve efficiency or flavour by bringing your
pale malt mash into the optimal pH range consider using some of Weyermann's Acidilated malt (3EBC) or similar acidic malts or some of pH5.2 by Starsan (they guarantee it will bring your mash to 5.2 and hold it there). Both will save a lot of time and effort in boiling, adding minerals, cooling and removing your water from the chalk sediment (time, hassle, energy! I'd rather be drinking beer). Interestingly, if Palmers stats on minerals in the various brewing cities of the world are correct both Munich (359 mg/L CaCO3) and Vienna (686 mg/L) (which I doubt as they seem extreme) both have higher water hardness levels than Adelaide (123 mg/L) and both produce excellent pale beers. (these calculations are relying on Palmers calcium and magnesium stats and are run through a water hardness calculator at
http://www.lenntech.com/ro/water-hardness.htm )
In the home brewing environment, it appears the consensus of Palmer, Graham Wheeler and many experienced bloggers is that water pH readings have very little to do with the resultant pH of the mash (In Adelaide the municipal water pH is consistantly between 7 [neutral] & 7.5 [bairly akaline], exactly the same as Melbourne).
So in summary, I would only play around with water treatment if you are finding the pH of your mash (ie you have tested
mash pH and it's 4.5 or something way out)is interfering with saccharification efficiency, or more importantly the flavour of your beer (ie astringency extraction) . You should experiment and test different brews with what water you have before you expel energy (and money) on changing your water mineral make up. If water treament is going to be easier for you than acid rests or additions of acidulated malt (I don't see why) I would begin by trying a bit of water treatment on some pale malt mashs by adding some calcium sulphate to reduce carbonates (in hard water) or the addition of calcium carbonate on dark malts (in soft water). If it improves the flavour of the beers as opposed to brews where the water hasn't been treated I would continue. Otherwise I wouldn't bother.
