What happens when mash pH is too low?

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Martybhoy

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I live in a very soft water area, and my IPAs and similar pale beers usually turn out as expected. Amber beers too. My dark beers however are never anything special and I'm wondering if with all the dark grains, my mash pH gets too low.

I struggle to hit FG with dark beers and they usually taste bland - never any roasty flavours. It's a bit like Guinness I suppose.

The total alkalinity of my water as CaCO3 is 7ppm, and my water pH is 8.24.

Anyone got any suggestions?
 
You could steep the dark grains seperately so that you are only mashing as per a pale ale and likely to hit a better pH
 
You could steep the dark grains seperately so that you are only mashing as per a pale ale and likely to hit a better pH
Would I just use the same amount of dark grains as per recipe if I did this? Or are there adjustments required?
 
Don't understand this - ph of 8.24 is alkaline. Neutral is 7. My own water supply is somewhere around 6, can't remember the exact figure but it may well be less as it comes straight out of a peat bog and is noticeably more acidic in summer when there's less rain to dilute it.
And yes my pale ales and bitters are very nice, but stout isn't unless I use supermarket water. I used Tescos Ashbeck last time and it came out really nice but it's ph is only 7.8 - less than yours.
 
That's where my knowledge of water treatment falls.

I'm sure I read on here that the total alkalinity is what I should be paying attention to, rather than my water's pH.

Last year my water's pH was 7.68. retested this summer and it's 8.24. total alkalinity was 7ppm (CaCO3) in both years. When I look at water profiles, 7ppm is always really low, leading me to think my water is soft.
 
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Low attenuation is typical of a low mash pH. Have a look at this chart from Braukaiser. As you can see the attenuation drops quite quickly below 5.2 pH.
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And you're right, the water's pH is mostly irrelevant, especially when it's as soft as yours.

Dan's suggestion of steeping the dark grains separately is a good one, and very easy to do. Simply steep the roasted grains (and crystal malts over 100°L if you want) in 75°c water at a ratio of 4L/kg for 5 mins, then strain it off and add the liquid to the last 5-10 mins of the boil.

Or you could try cold steeping which gives a smoother roasted flavour. Same method as above but using room temperature water and steeped for 24 hours.

Of course another option, and a simpler one, is to add the dark grains to the mash at mash-out. I've used all these methods and they all work fine.
 
You could steep the dark grains seperately so that you are only mashing as per a pale ale and likely to hit a better pH
Great suggestion. Or, adding the dark grains at sparge, if you want to keep everything in on pot.

Sounds like the problem is more flavour than attenuation/efficiency, and perhaps a Chloride and Sodium addition would help. Try adding some table salt to the boil. You could even add some to the glass to see if it enhances one of your bland dark beers.
 
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Cheers guys. Food for thought.

I'll give the steeping a go. I didn't add any water treatment to my last stout, as it was a last ditch effort to brew one using un-altered tap water.

Its something I've looked into since so I'll look at water treatment for my next stout.

And tonight I'll add a little salt to one as a test
 
Don't understand this - ph of 8.24 is alkaline. Neutral is 7. My own water supply is somewhere around 6, can't remember the exact figure but it may well be less as it comes straight out of a peat bog and is noticeably more acidic in summer when there's less rain to dilute it. ...
I discussed this earlier in the year so 'scuse me if I'm being repetitive (might have been a different forum?).

You have your own supply (IIRC). I, and I'm presuming "Martybhoy1980", have municipal treated supplies, and the water company will try to keep the pH between "acceptable" limits. As the drought took hold this year I guess acidity increased and the water company might have "overdone" the correction (or perhaps the correction never changed and the acidity decreased?), so my water supply leapt up from pH7.5 to pH8.5.

But to put that in context: I also have soft water (off moorland) and I will acidify my sparge water so it is below pH6: This requires me to add a fraction of a millilitre of phosphoric acid to 50-60 litres of pH7.5-8.5 water. I don't know why I bother. Soft water has a tiny buffering ability so pH can be swung about all over the shop.



I have an image of water treatment works adjusting the pH. A slowly revolving perforated plate dosing water as it tears by below with white powder (chalk?). It was on TV a while back, let me think, Blue Peter some 50 odd years ago!
 
I live in a very soft water area, and my IPAs and similar pale beers usually turn out as expected. Amber beers too. My dark beers however are never anything special and I'm wondering if with all the dark grains, my mash pH gets too low.

I struggle to hit FG with dark beers and they usually taste bland - never any roasty flavours. It's a bit like Guinness I suppose.

The total alkalinity of my water as CaCO3 is 7ppm, and my water pH is 8.24.

Anyone got any suggestions?
Don't put a disproportionate amount of importance behind water treatment, especially when you've got soft water (hard water, or something with a lot of dissolved solids, can have "issues"). An often quoted remark is water treatment is a "seasoning", it can make what is already good, better - it won't make something bad, good; look for something more influential.

I'm currently mashing at pH5.0-5.2, including dark beer. I've no explanation why mash pHs have decreased sharply this year (was pH5.2-5.8) or why the water treatment calculators started failing me. But I can still brew decent beer. The dark beer brewed this year was a bit "not so good" but that was kooky yeast and the taste was far from "bland"!

When I was trying to get to grips with the fall in pH I saw all that Braukaiser stuff ("Strange-Steve's" post above) but when you look at it closely you can see you wouldn't notice the changes to "yield", nor the changes to attenuation unless you actually wanted a highly attenuated dark beer (certainly not something I'd be trying for).
 
I went with steeping the dark grains separately and adding at the end of the mash.

OG was 1.069, and FG (3 weeks later) is 1.021. Low attenuation strikes again. I've roused the yeast and increased the temp, but it didn't budge .

Assuming there is no fermentation left in this, should I bottle anyway? I doubt it'll be much good , but binning a beer goes against my Scottish nature.
 
Great suggestion. Or, adding the dark grains at sparge, if you want to keep everything in on pot.

Sounds like the problem is more flavour than attenuation/efficiency, and perhaps a Chloride and Sodium addition would help. Try adding some table salt to the boil. You could even add some to the glass to see if it enhances one of your bland dark beers.

The only time i tried this i got about half the extraction i should of. A not so black BIPA.
 
Soft water is a good starting point. You need to get the wort pH down to 5.2 by adding water treatment salts to the mash. Calcium Chloride addition helps too. Another beneficial technique is to add brewing caramel, as if the grist composition of high coloured roasted malt / barley goes above 8% mash drainage is poor. Commercially high roast barley brews requires enzyme addition which is best avoided for the home brewer.
 
I went with steeping the dark grains separately and adding at the end of the mash.

OG was 1.069, and FG (3 weeks later) is 1.021. Low attenuation strikes again. I've roused the yeast and increased the temp, but it didn't budge .

Assuming there is no fermentation left in this, should I bottle anyway? I doubt it'll be much good , but binning a beer goes against my Scottish nature.
What yeast and mash temperature did you use? That's 70% attenuation which isn't unreasonable, and you have 6.3% abv. My milk stout finished at 1.020 and it's only 4.7%, there's also only 100g of lactose in a 15L batch so it's not doing much to boost the FG. I think you're beer will be great, but it doesn't (generally) hurt to be cautious. :-)
 
I used Imperial yeast A10 Darkness, which has an attenuation range of 71-75%. So I guess I'm just 1% off the bottom of the range. I mashed at 65°C. Previous mashes at 67°C or higher resulted in low attenuation.

On that basis I'll bottle it. This brew was a last effort to try make a good stout, steeping the darker grains separately. Might as well see it through

Cheers
 
Yeah, I'd have expected higher too in that case but sounds done if it's stable. Have you tried adding sodium bicarbonate to your water? I have soft water too and even my amber beers end up between 5.0 - 5.2 if I don't add some bicarbonate. I use bru'n water to do the calcs and I've learned that it estimates 0.2 - 0.3 high for me, last brew I aimed for 5.6 and a bit and hit 5.4 dead on which was what I wanted. Also got 80% efficiency, maybe the two were related?

Good luck.
 
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