Weird boiled water taste experiments
I live in Nottingham,UK and I thought that my water tastes fine. However after starting AG I found that whenever I try to brew a pale ale I can detect a specific aftertaste like an overly boiled water for tea, reminiscent of pipes....
This taste seems to be only detectable in boiled water, and not straight from the tap.
Here is my water report:
Ca 75mg/l (determined with Salifert kit)
Mg 15mg/l Na 31mg/l
SO4 95mg/l Cl- 42mg/l
HCO3 130mg/l as CaCO3 (determined with Salifert KH/ kit)
I have tried two experiments to determine the source of the weird taste. In the first one I just boiled 4l of water for an hour down to 2.3l, cooled it down, aerated it and had a taste. It had a lot of CaCO3 precipitate and that peculiar astringent taste on the top of the palate.
In the second experiment I used fresh tap water and CRS to lower the carbonates to 30mg/l CaCO3, boiled again, cooled, aerated. And...it had the freaking taste again :(
I tried adding some Calcium chloride and that did mask the taste a bit, but I think it is just the overwhelming taste of the chlorides masking, not so much as fixing the taste. Now when I brew a slightly darker beer or even better a stout I cannot detect the taste, but I believe this is because the richer malt character is covering the water.
Could this weird taste be due to iron from my pipes (report says Iron 11micrograms/l)? I would hate to invest in a RO system...is there any way to fix those Brita jars to filter water automatically without me replenishing 40l water 2l at a time all night?
I would appreciate any advice you could offer for this peculiar problem that keep me awake and prevents me from brewing pales.
The sulfate is a bit high and the combination of modest chloride and sodium might be creating an antagonistic flavor effect for you.
I'm not surprised that the boiling experiments did not alter the taste since the chloride and sulfate are contributors to permanent hardness and are not affected by the boil. You have confirmed that calcium and carbonate are relatively taste neutral and their loss through boiling or acidification did little to change the overall water flavor. The acid experiment actually reduced the temporary hardness and added permanent hardness with the addition of the chloride and sulfate. If anything, I would suspect that the CRS treated sample might have been a bit more astringent.
The 11 ug/L iron should be well below the taste threshold. Some say the taste threshold is somewhere between 100 and 300 ug/L for iron.
I assume that since you were experimenting with CRS, that you are up to speed on acidifying your sparging water so as to avoid tannin extraction and bringing your mash pH into proper range. Given the potential to contribute to the antagonistic flavor effects that I think come from sulfate and chloride, maybe you should consider switching to another acid such as lactic or phosphoric.
A good way to check if the problem is excessive sulfate or chloride is to dilute the tap water with distilled or RO water. That is likely to reduce the flavor.
To add to Martin's information, anytime you boil water you will be concentrating the minerals in the sample which would make it more prevalent.
Martin is correct that dilution is the solution to pollution. :)
When you boil the water as soon as ebulition commences you have effected all the bicarbonate reduction you are going to get and so there is no point in boiling further. All you do beyond that point is concentrate the minerals that are still in solution. Boiling to half volume doubles these concentrations. You might not be able to taste them in the tap water but when you double the concentrations that may be enough to push them over threshold.
When you use CRS you are simply replacing bicarbonate with sulfate and chloride in whatever ratio the product contains the two acids. Boiling after adding CRS is pointless. It will only increase ion concentration as noted above.
Chloride is used in many foods (including beer) as a sweetener. Obviously this only works up to a point beyond which the textbooks say the flavor becomes 'pasty' whatever that means. This may explain why the addition of calcium chloride after the CRS treatment seemed to improve things. So apparently the culprit here is the sulfate. Or more to the point it is your palate - you don't like the taste of sulfate (and I am with you here but some people do like it).
Another possibility is that the extended boils required to reduce the volume to about half may have dissolved something from the pot you are doing the boiling in. If the pot is stainless this should not happen but if it is aluminum or copper this might be an explanation. You won't taste iron until it gets up to about 100 ug/L.
As a general observation the industry has discovered and home brewers are discovering that low mineral water makes better tasting beer. Style, in some cases, of course calls for high mineral content but in general the softer the water the better though some chloride and some calcium should be present in most cases.
If, as your taste tests seem to indicate, though I'd try the first again with a shorter boil, your taste preference is for low mineral water then an RO unit is probably your only way out. Low throughput ones aren't that expensive.
Thank you all for the helpful replies!
Just to clarify- I used to experiments to mimic what happens when I brew a beer. I use the brew in a bag methods and treat 40l water with 19-20ml CRS, mash the grains , pull out and then down boil to 28-25l. That is why I did the long boil for the water, trying to emulate its contribution to the beer taste :)
Treating 4l water with 2ml with CRS adds 45mg/l SO4 and 28Cl-. Pre-boil sum 140 ppm SO4 to 70ppm Cl- / . Post boil this should lead to 224ppmSO4 and 112ppmCl-. I guess evaporating 40% is a bit too much in my experiments as I do not have the grains to absorb some of the water but I can try doing and experiment 3.5 to 2.5 and see if that makes a big difference.
It seems that really sulphate (in 2:1 to chloride) is the reason for this weird taste. However that goes against what is said for English bitters and pale ale- that sulphate up to 150-200ppm is fine and that to accentuate hop bitterness a level of 2:1 is OK. I do like the pale ales in the pubs here, but mine have a dry aftertaste and do not finish as pleasantly. It is quite puzzling that Burton can get away with extreme sulphate and I cannot.
PS Btw in the unfortunate pale ale that I brewed I did not use CRS but lactic acid. Back then I was ignorant about water chemistry and it was only after I tasted it that I started reading up on it and experimenting with water.
The old brewmasters of Burton might well have had to deal with the high sulfate levels we see in some of the published profiles for that region but it's not likely they do so today. They probably use mains water produced by an authority that would choose a source other than one of the extremely gypseous wells we associate with Burton beer. There is a secondary MCL for sulfate of 250 mg/L. Above that the water is considered to taste bad and suppliers while not required to honor a secondary MCL usually try to do so if they can.
I can vouch for the bad taste with sulfates above 250. Added 20 g of gypsum and 7 of epsom salts to my mash....ruined the batch, undrinkable, the minerals over power the hops all together, and I think I "OD'ed" on sulfates or epsom salt, or something, I had a migraine so bad and puking so hard the next day after a SIX PACK! It felt like the worst hangover you could imagine times 10
Overdosing on any ion is not a good recipe for brewing. I'm OK with 300 ppm sulfate in a pale ale. But in discussions with Colin Kaminski, he mentioned his personal preference reached all the way above 800 ppm sulfate in some pale ales. He said his customers did not necessarily like that sulfate level though. He did go on to say that his house pale ale is brewed with about 250 ppm sulfate.
Thank you again everyone.
I did a small experiment with serial dilutions of a 1.8g/l CaSO4.2H2O solution and determined that for me sulphate brightens up RO water up to 50mg/L as SO4, it is not too overwhelming at 100, but 150 is pretty noticeable on its own and 200ppm I found intolerable. I tried adding CaCl2 to the 150ppm SO4 and it did not do much masking even up to 600ppm because I feel the salty sensation in the beginning and sulfate lingers longer. For the 100ppm SO4 concentration the 100ppm Cl was beneficial for my own palate. I think the chloride was tolerable and not undrinkable up to 250ppm as most authors have stated, but I was amazed that my personal threshold for sulfate tolerance is so low.
I may convert to the darkside and use RO and will aim to bring down the levels of sulfate around 50 from now on. Found a RO system for 40 pounds off the UK ebay so may go for it and a cheap-o pH meter around the same price tag.
I hope this combo would improve my pales and I shall try to find some Burton lovers to drink my Delinquent Pale ale with excessive sulfate :)
Again, a big thank you to everyone that helped me pin the weird taste down :)
I love the idea of doing the taste test experiment to get a handle on the flavor thresholds. I might have to do that.
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