CRS lost its mojo?

[The-Engineer-That-Brews]

Had to add 25% extra CRS today to hit my target mash pH: 24ml vs. 19ml from my normal spreadsheet.
Well that justifies getting a pH meter, and explains the efficiency issues with my last couple of brews.

Having checked the bottle, I see it’s got a ‘use by 06/21’ … oops.
I presumed that being just a mix of hydrochloric and sulphuric acids it would be pretty stable - but maybe not. Can any chemists out there shed any light?

I do have a new bottle, so I was thinking I might do a comparative test. If I dilute it sufficiently with de-ionised water then could I do a titration with the Salifert KH test…?

EDIT: I tested the old versus new bottles of CRS and they performed exactly the same - so whatever the problem is, it’s not that.

UPDATE: in all my tests the CRS has been very reliable and has reduced alkalinity exactly as much as it‘s meant to. The problem seems to be that the mash calculation spreadsheets are a lot less accurate than I thought they were. Moral of the story: always measure your mash pH

 

[The-Engineer-That-Brews]

If I dilute it sufficiently with de-ionised water then could I do a titration with the Salifert KH test…?

Actually it’s simpler than that isn’t it: I can just add a measured quantity of each to samples of my tap water and check how much of the bicarbonate has been neutralised.

 

[Sadfield]

Perhaps your water has changed.

 

[The-Engineer-That-Brews]

Perhaps your water has changed.

yes I wondered that, so I did a KH test and I think it’s the same as I used in the water calc - but I’ll check

 

[The-Engineer-That-Brews]

Perhaps your water has changed.

Also having tested/corrected the pH today I was back to my normal mash efficiency of 82% whereas my last couple of brews (Feb/Mar) have both been well below 70% so if it’s the water then it would have to be a fairly long term change?

 

[The-Engineer-That-Brews]

OK it seems that the reason for the unexpectedly high pH was NOT a loss of strength of the acid. I've just done titrations with both the old and the new batch and they performed exactly the same: 0.5ml/l reduced my bicarbonate by 120ppm (from 349 to 229), consistent with the expected result.

So if the acid was as expected and the water hasn't changed much, that really only leaves either the malt or the mineral additions (but these were small: 100 mg/l gypsum and 140 mg/l epsom). Investigations continue.

 

[The-Engineer-That-Brews]

Checked the pH meter calibration and it’s bang on, and I just checked the quantities and specifications of the malts were correct - so I’m scratching my head here. I think the next step is to do a mini-mash just on the stove top and see what pH I get from that.

 

[Pennine]

Any reason you don't use phosphoric? I haven't read good things about crs which is why I never used it.

 

[The-Engineer-That-Brews]

Any reason you don't use phosphoric? I haven't read good things about crs which is why I never used it.

No reason at all @Pennine and I have a friend locally who swears by it. I do find the CRS easier to get hold of though, and I like the way it boosts my sulphate and chloride levels without increasing my already-high calcium.

I have also read elsewhere that phosphoric can cause precipitation of calcium; and while there seem to be differing views on either side of the pond about how much calcium is desirable I have so far followed the advice of others here to keep it above 100 mg/l.

When you say you haven’t heard good things about CRS, do you mean you’ve heard bad things about it? I’ve seen at least one very negative comment about it from Martin Brungard; but at the very least it seems that others beg to differ :-)

 

[AJA]

Any reason you don't use phosphoric? I haven't read good things about crs which is why I never used it.

Main downside of CRS is that you are increasing SO4[2-]- and Cl[-], and sometimes it's impossible to get your water profile to work out if for example you are going for a low sulphate profile. I use some concentrated HCl in this scenario which is also very cheap. Otherwise there's not much to go wrong with it, it's just hydrochloric and sulphuric acid, so I'm unsure what the bad press relates too. If I was Brupaks though, I'd add phosphoric acid too in the formulation to mitigate the above problem.

I've convinced myself that precipitation of calcium with phosphoric acid is not really an issue, as calcium would have to be very high to shift the equilibrium toward precipation, at levels which don't concern brewers. Only trouble is phosphoric acid is reasonably hard to get. It's available on ebay etc but I'm not convinced this is food grade.

 

[foxbat]

Only trouble is phosphoric acid is reasonably hard to get. It's available on ebay etc but I'm not convinced this is food grade.

It's available in 75% concentration from Geterbrewed and BrewUK.

 

[Pennine]

Main downside of CRS is that you are increasing SO4[2-]- and Cl[-], and sometimes it's impossible to get your water profile to work out if for example you are going for a low sulphate profile. I use some concentrated HCl in this scenario which is also very cheap. Otherwise there's not much to go wrong with it, it's just hydrochloric and sulphuric acid, so I'm unsure what the bad press relates too. If I was Brupaks though, I'd add phosphoric acid too in the formulation to mitigate the above problem.

I've convinced myself that precipitation of calcium with phosphoric acid is not really an issue, as calcium would have to be very high to shift the equilibrium toward precipation, at levels which don't concern brewers. Only trouble is phosphoric acid is reasonably hard to get. It's available on ebay etc but I'm not convinced this is food grade.

Yes I plugged it to the calculator prior to buying to treat hard water in suffolk and the profiles that came out were less than optimal.

Like foxbat said you can also get 75% phos at the homebrew company for a few pounds. I just went that route and never looked back. 3ml of acid for most batches and the bottle has lasted me a long time.

https://www.thehomebrewcompany.ie/index.php?main_page=product_info&products_id=3387

 

[Pennine]

No reason at all @Pennine and I have a friend locally who swears by it. I do find the CRS easier to get hold of though, and I like the way it boosts my sulphate and chloride levels without increasing my already-high calcium.

I have also read elsewhere that phosphoric can cause precipitation of calcium; and while there seem to be differing views on either side of the pond about how much calcium is desirable I have so far followed the advice of others here to keep it above 100 mg/l.

When you say you haven’t heard good things about CRS, do you mean you’ve heard bad things about it? I’ve seen at least one very negative comment about it from Martin Brungard; but at the very least it seems that others beg to differ :-)

Yes the same source, I was trying to figure out how to use it a while back and saw his comments. I think there was a thread on here about issues with it too. It is interesting about how far off it is, what calc are you using? Brunwater?

 

[Sadfield]

Would be interested to hear what the negatives are? Chloride and sulphate addition is a positive in my experience.

 

[chthon]

Would be interested to hear what the negatives are? Chloride and sulphate addition is a positive in my experience.

Probably because you can't change the ratio between them. So then you still need to add extra CaCl or CaSO4 depending upon what the recipe needs.

 

[AJA]

Would be interested to hear what the negatives are? Chloride and sulphate addition is a positive in my experience.

In general yes, but some source water is already high in either of these. E.g. my local water has sulphate >50ppm.
For a NEIPA I wouldn't want to add any more, and therefore CRS isn't suitable here. I still use it for over half my brews though.
Phosphoric seems much more one size fits all.

 

[Sadfield]

I do love minerals. I don't think I've ever had a beer of any style, where I've thought it was too much, but plenty of bland ones.

 

[AJA]

It's available in 75% concentration from Geterbrewed and BrewUK.

Thanks, I'll wait until I have to buy some more bits and will get some ordered.

 

[The-Engineer-That-Brews]

I do love minerals. I don't think I've ever had a beer of any style, where I've thought it was too much, but plenty of bland ones.

Absolutely agree. I’m typically aiming for around 200 sulphate, 100 chloride and about 150 calcium; but as my water already has 130 calcium, if I tried to get the SO4 and Cl by adding salts I’d blow the top off the Ca.
At the same time my ALK is up at 350ppm HCO3 so I need to neutralise that to get a decent mash pH. CRS therefore kills two birds with one stone for me.
Horses for courses, chacque un a son gout etc.

 

[The-Engineer-That-Brews]

Would be interested to hear what the negatives are? Chloride and sulphate addition is a positive in my experience.

I’m intrigued by the antipathy too, @Sadfield … I’ve wondered whether it might be because HCl and H2SO4 are *strong* acids and therefore dissociate completely in water