Campden tablets and pH

[inthedark]

Does the use of Campden tablets increase pH? I've been testing my water supply, and straight from the tap it is about 7.2, whereas the stuff I treated a few days ago is 7.7.

Is this to do with the treating, concentration through evaporation maybe, or just normal variation in supply do you think?

[inthedark]

OK, so I've tried to answer my own question through a slightly more controlled experiment, in the absence of any chemical understanding on my part

Just filled my boiler for (hopefully) a brew day tomorrow. pH tested from the tap at 7.7. Added 1/2 a Campden tablet to approx 25L, waited a few minutes and tested again - 7.2. Seems like a very large drop for such a small tablet but what do I know?

Just added 10ml CRS, hopefully I'll get a better idea now about how much will be needed to get it under 6.

[inthedark]

Was the temperature the same for both readings. I believe either the actual ph falls or the indicated ph falls with a rise in temperature...of course I could be talking arse

The readings were taken about 5 minutes apart I guess - do you think that would be enough to make a difference?

[Jim]

Well, I don't think that's a huge change; plus, it will probably be swamped by the acids formed from the grains when they're added anyway.

The pH of the water on it's own isn't a good guide to the mash pH (so I've read - might have been in the BBoB).

[inthedark]

The pH of the water on it's own isn't a good guide to the mash pH (so I've read - might have been in the BBoB).

Thanks, Jim, I have taken that on board, but my mash pH has been pretty enormous (upper 6's) so I wanted to get some idea of how much CRS to add whilst I'm not worrying about temperature loss on the day! - I'll check the mash pH too tomorrow to get some idea of how this has affected it.

BTW, I thought that a drop of 0.5 was significant because it took such a large amount of CRS to achieve the same drop. Some people here report starting with 0.3 - 0.4 ml/L but my water seems to be taking double that...

[hendrixcat]

I'm planning on using CRS for the first time next week. I'm in Dublin and my tap water has an alkalinity of 200ppm. I thought that the addition of CRS is more to do with reducing the buffering capacity of the water rather than altering its pH. If the bicarbonates are too high they mop up the acidity produced by the malt and leave you with a higher than optimal mash pH, mainly in pale beers. I have no problem brewing stouts, but that's no surprise for Dublin water.

On a different note, can anyone tell me if campden tablets work over a few minutes or do they require over night to get rid of chlorine?

[PieOPah]

My wife has just 'acquired' a book of pH Papers from work (about 1,000 she tells me).

I've never been too bothered about Water treatment, but I though that I would give it a go. All I need to do is buy some stuff to treat the water! I have Gypsum already so can use that if needed. Just need anything else (obviously if required).

I think that the next brew I do I'll get an idea of what the pH is and then I will buy whatever I need from there for future brews. It will be interesting to see what type of difference this makes to my beer

[steve_flack]

Personally I used to use phosphoric acid - brupaks supply it. It doesn't give a flavour to the finished beer. I'm using 5.2 now and early indications are good.

[hendrixcat]

Does anyone know of flvour problems when using lactic acid to acidify the mash? I used it for the first time a few weeks ago and there is a bit of a tang from the beer. I even tasted the tang in the sweet wort before boiling. I thought it was traditional to used lactic acid aswell as phosphoric.

[Seveneer]

I've been trying out lactic acid in my liquor and haven't noticed any flavour attributable to the acid.

Not saying it wouldn't but I've not noticed anything yet.

/Phil.

[Andy]

Isn't phosphoric acid supposed to form a coating on heating elements* ? The coating being effectively bone and very difficult to remove......



* believe this was a post on the UK homebrew list

[Seveneer]

I wouldn't put my bone on a heating element

I may have misread you post

[Andy]

I wouldn't put my bone on a heating element

I may have misread you post

[Andy]

Here's the post:-


Date: Wed, 14 Feb 2007 18:40:54 -0000
From: "Andrew Smith (I)"
Subject: RE: no boil water treatment

> For chlorine, add around 2 camden tablets per hectolitre.
> For hardness reduction you can add phosphoric acid.

Agree entirely for chlorine.chloramine but I cant agree with Phosphiric
acid in generl. It is fine if your HLT and Boiler are gas heated but I
would not recommend phosphoric at all for an electrically heated hlt or
boiler as the precipitate is Calcium Phosphate (IE BONE) and have you
ever tried removing bone from yopu elements (trust me from experience it
is not easy). If you hardness is not too high (say less than about
150ppm) you could use lkactic acid as calcium lactate is quite soft and
easily removable from elements with a light scrub. However best yto use
brupaks CRS which is a dilute mix of hydrochloric and suphhuric acids
which produces Calcium sulphate and calcium chloride both of which are
benificial and soluable to a high level so therefore no coating of
elements occurs at all

Andrew Smith (I)

[David Edge]

I would not recommend phosphoric at all for an electrically heated hlt or boiler as the precipitate is Calcium Phosphate (IE BONE) and have you ever tried removing bone from yopu elements (trust me from experience it is not easy).

I remove it from mypu elements as follows:

remove element from HLT and it in a plastic jug wedged so that you can keep the bits you want cleaning wet and the sparky bits dry.

pour in hot water almost up to the line

add 15ml phosphoric acid

leave for an hour, come back rinse, put back in HLT.

Piece of the proverbial. I need to do it maybe every twenty brews at in the HLT.