Water treatment and mixing water

[Chunk]

I've just started treating my brewing water. As a starter for ten, I followed Graham Wheelers book and used 10g Gypsum and 1g Epsom salts in 23 litres of water. When I read the mash PH it was off the scale ... the scale being 5.5ph to 4ph and off being >5.5.

Second time around I added 15g Gypsum and 1g Epsom salts ... mash PH still above 5.5.

My first question is: Is it best to just keep increasing the Gypsum amount by 50% until I see some difference or is there a better way to do it (I dont have a water analysis breakdown).

My second question is ... I can only treat 23 litres of water at once. For batches where I need more than that, could I "over treat" the 23 litres and then "dilute" it with tap water to get it back to the desired state ... or would that just not work? Would there be a scientific way to calculate how much to "over treat" by?

Cheers.

[ajdelange]

I've just started treating my brewing water. As a starter for ten,...

Not sure what that means.

...I followed Graham Wheelers book and used 10g Gypsum and 1g Epsom salts in 23 litres of water. When I read the mash PH it was off the scale ... the scale being 5.5ph to 4ph and off being >5.5.

That's a lot of gypsum which would be suitable for a Burton style ale but a disaster for a Pils. So tell us what kind of beer you intend to brew.

That level of calcium and magnesium added to deionized water would be expected to shift pH about 0.12 lower than if you mashed with untreated deionized water i.e. approximately 5.75 - 0.12 = 5.63 > 5.5 so if you water is low in mineral content the result is not surprising. If your water is laden with permanent hardness, a lower pH would be expected. If laden with temporary harndess pH would be higher.

Second time around I added 15g Gypsum and 1g Epsom salts ... mash PH still above 5.5.

Theses additions to distilled water would result in a pH reduction of 0.18 pH for 5.75 - 0.16 = 5.57 which is closer to 5.5 but, in cases of temporary hardness the result will be higher. Tell us how you measure pH.

My first question is: Is it best to just keep increasing the Gypsum amount by 50% until I see some difference or is there a better way to do it (I dont have a water analysis breakdown).

No! You are already at 381 mg/L sulfate with a 15 g addition. Most beers wouldn't do too well at that level of sulfate (though some would). I can't really tell you more without knowing what style you are aiming for and what your untreated water chemistry is. Spring for $25 and send a sample off to Ward Labs or contact the municipal water company and demand (politely, of course) a report.

My second question is ... I can only treat 23 litres of water at once. For batches where I need more than that, could I "over treat" the 23 litres and then "dilute" it with tap water to get it back to the desired state ... or would that just not work? Would there be a scientific way to calculate how much to "over treat" by?

Of course but I have to know the mineral content of the dilution water. If you dilute with DI (or nearly DI) water then simple proportions will give you the answer. e.g. if you added 15 g gypsum and 1 g Epsom salts to 23 litres of DI water the sulfate level will be 381 mg/L. If you then cut 3:1 with DI water the sulfate level would be 1/4 of 381 = 95.2 mg/L and similarly for other ions. There would be a slight pH shift as well - calculation of that shift is relatively complex.

[Chunk]

Thanks for the detailed response, much appreciated. The more I read about water treatment, the less I think it's worth me investing time in at the moment. General opinion seems to be that it won't be the difference between a good and bad beer.

I'm just starting out with water treatment, so apologies for any stupid comments/questions. I thought Gypsum is only used to add acidity and lower the PH of the mash ... 5.3 being the ideal mashing temperature for any beer. Other minerals etc in the water then being changed to match the style of beer.

My mash always registers above 5.5, so I've been adding increasing amounts of Gypsum to try and lower it. Is this approach fundementaly wrong?

[ajdelange]

The more I read about water treatment, the less I think it's worth me investing time in at the moment. General opinion seems to be that it won't be the difference between a good and bad beer.

I don't think it's one of the first things you want to master as there are plenty of others that will make the difference between a good and bad beer. Master making the ales you would typically find in pubs around London using untreated water and then, when you are ready to consider other styles, study what needs to be done to tailor what comes out of your mains connection to those styles.

I thought Gypsum is only used to add acidity and lower the PH of the mash ... 5.3 being the ideal mashing temperature for any beer. Other minerals etc in the water then being changed to match the style of beer.

It is but, as the example numbers in my last post show, it can only do it to a certain extent. Acid from other sources is needed to get pH into the region we want. Dark malt contributes some (London's traditional beers are darker than Burtons because more acid is needed) but, and this seems to be a well kept secret among home brewers, even more is usually required unless you use so much roast malt that you beer tastes like charcoal briquets. In the UK you have a product called CRS (Carbonate Reducing Solution) which is, AFAIK, a blend of sulfuric and hydrochloric acids. On the continent, especially in Germany and the Czech republic they use lactic acid produced by lactic fermentation of malt or wort. In the US craft brewers that I have spoken to tend to use acidulated malt or lactic acid if they worry about pH at all which some don't. I haven't heard any admit to using sufuric or hydrochloric though I certainly haven't discussed it with that many.

It's the calcium in gypsum that releases hydrogen ions when it coalesces with inorganic phosphate released by malt in the mash tun. Calcium from calcium chloride does this as well as does the calcium in calcium carbonate but each equivalent of carbonate ion produces 2 equivalents of alkalinity but the associated calcium in calcium carbonate only 1/3.5 equivalents of acid so calcium carbonate is seldom used.

Calcium is good for beer in many ways beyond just the decrease in mash pH so high levels of it are desirable in many cases. The accompanying anion (sulfate, chloride) need to be considered. Sulfate is associated with harsh, dry, scratchy bitterness with some hop varieties i.e. those used on the continent so continental brewers stay away from sulfate from gypsum and do not acidify mash with sulfuric acid. The interraction of sulfate with English hops is, conversely, a key component of the profile of British ales so gypsum (if not already in the water as it is aplenty in Burton water) is often added and/or CRS used to lower mash pH.

My mash always registers above 5.5, so I've been adding increasing amounts of Gypsum to try and lower it. Is this approach fundementaly wrong?

That depends on your water (which I now have a rough idea about) and the style of beer you are trying to brew. It also may depend on how you are measuring pH. The strips are notorious for their innacuracy both because the precision (typically 0.3) units is too low and, over here at least, they seem to exhibit a bias. A pH meter is potentially much more accurate but until you learn how to use one they can lead you astray as well.

[DBear]

ajdelange wrote:
Sulfate is associated with harsh, dry, scratchy bitterness with some hop varieties i.e. those used on the continent so continental brewers stay away from sulfate from gypsum and do not acidify mash with sulfuric acid.

I have not heard this before. Is there a reference to this I can read? I brew belgians and use combinations of continental and US saaz, hallertau, tettnanger along with sterling, vanguard, mt hood, liberty.

My Ward lab report loaded into Palmer's spreadsheet gives me and SRM range of 8-14 (don't have the RA at my fingertips). So I will use calcium chloride and/or gypsum to bring down mash pH for my lighter beers. Some beers seem harsher than others so I need to check my notes (of course all other variables are assumed to be perfect ).

[ajdelange]

Narziß (Abriß der Bier Brauerei, p p98), in discussing reducing mash pH by the addition of gypsum points out that sulfate remains in the beer and that this is bad for flavor. He therefore recomends the use of calcium chloride citing the chloride ion's ability to lend "vollmundige, weiche, and mild" (full bodied, soft and mellow) though sometimes somewhat salty qualities. He compares with the "trockenen" (dry, which he puts in quotes) quality associated with gypsum.

Moll, in Handbook of Brewing surveys the literature WRT to various ions and has this to say about sulfate:

"Sulfates directly influence dryness and can influence the amount of volatile sulfur; therefore, lower levels may be preferred for mild beers according to taste."
"Sodium sulfate gives astringent beers"
"Magnesium carbonate is transformed to magnesium sulfate [epsom salts] which is bitter"
"By addition of calcium sulfate into the brewing water, the hop aroma can be accentuated..."

WRT chloride he notes palate-fullness (probably a better translation for vollmundige) and body but notes that when chloride gets too high the beer becomes "pasty".

DeClerck (Vol. 1 p79) says: "Sulfate ions give beers with a drier and more bitter flavor; whereas chloride ions give beers with a mellower and softer palate."

I think you will find similar statements in other brewing texts. But the best way to explore it is to split a batch, one half made with high sulfate water and the other with high (but not too high) chloride water. Don't do this on a Pils because you will ruin the beer.

[DBear]

Thanks for all the references ajdelange!

WRT chloride he notes palate-fullness (probably a better translation for vollmundige) and body but notes that when chloride gets too high the beer becomes "pasty".

The above statment lept out at me describing my latest batch. I accidentally added enough CaCl to treat 10gals of my water to my 4 gal mash and the sample from the fermentor had a taste i could not identify but "pasty" hits it on the head.

-Cheers