Gypsum/Calcium Chloride additions

[lordnoise]

Now that I've sorted my water (South London) out for brewing a series of single hop Pale Ales (4.8 ABV) using CRS and DLS to get an averagely balanced beer for the style I'm wondering how much Gypsum per litre to add to begin to 'sharpen things up a bit more - likewise with Calcium Chloride to round things out a bit (for when I move on to the darker side !). Further should I expect a significant change in Ph during mashing (I use a meter) ?

[lordnoise]

Thanks .. err .. Chris - I'm happy that I've sorted out a pretty good average Pale Ale liquor regime using CRS and DLS - I'm hittiing around Ph 5.3 everytime and the beers are very drinkable .
What I'm trying to do now is explore the sharpness that Gypsum can give a beer (I remember tasting some experiments at a Brew school someone had done using different ratios of Gypsum to Calc Chloride and being surprised at how complementary the sharpness of more Gypsum was in a hoppy beer. Stones bitter is the only commercial beer that I've tasted (2 years ago) that approaches the mouthfeel/flavour. It really was quite sharp and therefore refreshing (fresh barrel so no bugs !).
My brew length is indeed around 25 litres so will I be okay with 10 gms of Gypsum added to the mash (along with my standard DLS addition of 11.5 gms) ?

[mysterio]

If you haven't checked it out already, google for BreWater. It's a free programme that helps you calculate your water salt additions. You can enter your own water profile, a target profile from a list of pre-entered ones (Edinburgh, Burton, London, Dublin etc). Then you can play about with the sliders (gypsum, cacl, NaCl etc) until you're close. I would suggest you not use DLS at all unless you know the composition of it. My current 'English' profile for bitters is 400ppm sulphate, 200ppm chloride, and whatever calcium that gives you from making it up with gypsum and CaCl.

[lordnoise]

Thanks mysterio I'll check out the Brewater site. There is a thread on here which deals with the composition of DLS and If I remember rightly it was thought to be a roughly 50/50 mix of Sulphate and Chloride. Interesting that you use a 2 to 1 ratio - I think I'm going to try 3 to 1 to try to really emphasise the Sulphate effect. As I'm putting 11.5 gms of DLS in to the mash already I think another 10 gms might be interesting - or not as the case may be ...

[ianmagson]

Let us know how you get on with the Gypsum experimentation - I for one would be interested to hear about the effects it has.

[Aleman]

Careful with the water calculators out there. I know Promash has got it wrong, and I am fairly sure that brewater is incorrect too . . . both ignore the water of hydration of the salts (the salts have a couple of molecules of water bonded to it) and as such underestimate the weight of the salt you are adding This water calculator is pretty damned good . . . although I preferred the earlier incarnation . . . you can set the chloride to sulphate ratio you want . . . and then set the levels of chloride and sulphate you want in the beer . . . . and it does the calculation for the correct amount of salts to add. . . . . Its too easy to get carried away though

[ianmagson]

Aleman, do you know anything of the Beersmith water calculator as I used that for my last brew?

[Aleman]

Sorry Ian, I don't use Beersmith so can't really comment .. . . . an easy way to test though would be to add the same amount of gypsum(say 10g in 25L) in Beersmith and Grahams Calculator and see if you get the same result for the calcium and sulphate levels . . . if you do then Beersmith is doing it properly.

[boingy]

Careful with the water calculators out there. I know Promash has got it wrong...

Aleman, I find this a bit disturbing given that I'm using Promash for my water calcs. Can you be more specific about the error? Does this mean I have been adding too much adjustment stuff to my water?

(Boingy wanders off to try some other water calulators...)

[Aleman]

Careful with the water calculators out there. I know Promash has got it wrong...

Aleman, I find this a bit disturbing given that I'm using Promash for my water calcs. Can you be more specific about the error? Does this mean I have been adding too much adjustment stuff to my water?

(Boingy wanders off to try some other water calulators...)

Ok to over complicate an already complicated topic

Calcium Chloride (CaCl2) is found in two forms (probably more . . . but we'll keep it simple) Anhydrous - CaCl2 and hydrated - CaCl2.2H2O . . . . Promash uses the anhydrous weight (MW 101.983) for its calculations . . . but the most common form that we can get hold of is the hydrated form (MW147.014) . . . . . so you are adding less than promash calculates . . . . For gypsum the figures are CaSO4 (MW 136.142) and CaSO4.2H2O (MW 172.172)

[boingy]

Cheers for that, Aleman.
I've checked the label on my Calcium Chloride flakes and needless to say there is no sign of any chemical formulae or of any qualification of the variety of CaCl. I am reassured that I am under-dosing rather than over-dosing. Last night I compared 3 different water calculators and got 3 different results. And that's before I take into account the fact that my tap water chemistry probably varies week by week.

It's a good job this brewing lark is not a precise art....