Hard water adjustment

[Enda]

Hi,

I am in the process of having my water tested for the main flavor ions. At the moment I only know the total alkalinity which is 200ppm and a rough value for total hardness, around 300. I have access to phosphoric acid and calcium chloride and have used brewers friend online calculator to calculate the acid additions I need to get the ph down to 5.4 for a pale hoppy ale. My one worry is calcium loss, I am not sure how much calcium chloride I need to use. So my question is do I need to wait for the lab results to come back on flavor ions or can I go ahead and adjust the water with the current information?

Many thanks

 

[ajdelange]

There won't be any calcium loss. You can guess that the calcium hardness is about 2/3 of the total or 200 corresponding to 80 mg/L Ca++. Best to have the complete test from Ward Labs (or a lab that provides similar service) of course rather than guessing.

 

[Enda]

Great thank you very much! So I can go ahead with the acid additions to adjust for ph, great. I will report back when I get the complete report. Just one last question, I also know another brewer who only uses calcium chloride for his ph adjustment, splitting it between the mash and kettle, would you recommend adjusting with acid over this technique?

 

[ajdelange]

In general, yes. It takes quite a bit of calcium to effect much of a pH change. Three and a half equivalents (70 mg) per liter of calcium are required to produce 1 mEq/L of protons. Two liters of water treated to 70 mg/L calcium would typically carry 1 kg of malt which typically has buffering of about 35 mEq/kg-pH. Two mEq of protons would thus shift its pH ~ 2/35 = 0.06 pH. This assumes the alkalinity of the water is 0. Additional protons would be needed to neutralize any alkalinity in it.

In cases where you have some dark malt and/or where a mineralized flavor profile is sought you may be able to handle the needed pH shift with just calcium chloride or calcium chloride and calcium sulfate.

 

[Enda]

Hi,

So I got my water report back from the lab, and this is what they gave me:

Calcium 62.7
Magnesium 21.5
Sodium 14.1
Chloride 20.8
Sulphate 26.2

So at the moment we have been using 10% phosphoric acid to get our ph down to around 5.2-5.4. The beers have been coming out quite nice but I was wondering if this is the best route to go or should I also look at additional salt additions.

 

[ajdelange]

Those numbers are consistent with an alkalinity of around 200 (what you reported in #1). That's quite a bit of alkalinity to remove with acid as it implies that your beers will have a lot of phosphate but if you don't taste the phosphate then no problems. You definitely don't want to add more salts (unless you are looking for beers with a mineral quality) but you might want to try going in the other direction: brewing with RO water or a blend of RO water to see if you like low mineral beers better.

 

[Enda]

Great, RO water is definitely something we are going to look into. In the mean time would you recommend switching to a different acid, such as lactic? Also is there a beer style you feel would best suit our current water profile?

Thanks again, this is very helpful.

 

[ajdelange]

Phosphoric is often preferred to lactic as it is more flavor neutral. If you want lactic flavor then you could experiment with that. The 'we are going to look into' suggests that you are a commercial operation. I don't recommend this to home brewers but hydrochloric and sulfuric acids can be used to decrease alkalinity and simultaneously increase chloride and/or sulfate ion both of which you might well want to supplement for, in the first case, smoother, rounder, fuller beer and in the latter more assertive expression of hops bitterness. OTOH you would want less sulfate for some beers (delicate lagers).

You ought to be able to brew a range of beers with this water especially as modified by additional chloride and/or sulfate. A good approach is to brew with what you have and add additional chloride and or sulfate on an experimental basis during taste tests.

 

[mabrungard]

Yes, 200 ppm alkalinity is pushing it with respect to neutralization with acids. Phosphoric acid is one of the least flavored acids and should be your first choice. Lactic is probably going to impart a noticeable twang to the flavor. Other options that you might consider are hydrochloric or sulfuric acids, excepting that they are much more hazardous to handle and they require more care. A final consideration is that using a combination of acids can help avoid the flavor impacts that a single acid might produce.

 

[Enda]

A mixed acid solution sounds interesting. We just ordered some lactic so maybe we can try a mix of that with the phosphoric. Since we started adjusting with phosphoric in the mash I feel like our beers have improved but with maybe a slight dullness in flavors, is this characterisitc of the phosphate flavor? I will also look into the more dangerous acids but maybe RO is the way to go in the long term.

Thanks again for all your help.

 

[ajdelange]

Can't say on the phosphate flavor as I don't use it (RO for everything) but you might consider looking for that flavor in a can of soda. These are loaded with phosphoric acid (they were called 'phosphates' instead of 'sodas' in my parents' day).

'Dullness in flavors' is sometimes associated with high mash pH. I'd check that too.

RO certainly has its advantages but it represents another capital expense, has to be maintained....

 

[Enda]

Hi guys,

Sorry for opening up an old thread, but I just wanted to give some updates and ask a few more questions. We have been adding phosphoric acid and hitting our desired mash/boil phs. Recently we have also started adding CaCl and CaSo depending on the beer, and have seen improved clarity. The question I have is there any kind of reaction associated with the salts and acid that needs to be taken into consideration?

Many thanks

 

[ajdelange]

I assume that you mean a reaction between added salts and added acid. There is one and that is when phosphoric acid is used with high levels of calcium. Appatite (hydoxyl calcium phosphate) is very insoluble (your teeth are made of it) but at mash pH the amount of phosphate which becomes PO4-3 which reacts with calcium is very small so the precipitate only forms at very high calcium levels (at mash pH).

Other than that of course we rely on the reactions of the acid in supplying protons to the proton absorbing components of the mash to effect the lower pH.

I'll also note that the acids are not particularly dangerous if handled appropriately which means using common sense. I don't recommend them to home brewers because more than a few lack that 'common' sense and I don't want to expose myself to liability by suggesting that they do something which can result in injury if common sense doesn't rule. The possible exception here is concentrated sulfuric acid which will rip the water out of anything including a molecule your body is using for something else. I don't recommend that anyone but professionals handle concentrated sulfuric acid. Fortunately suppliers to brewers often offer diluted forms of these chemicals that are quite safe to handle, using common sense. There is, for example, an outfit in the UK that sells an equinmolar blend of sulfuric and hydrochloric acids specifically for brewing pH adjustment (and another company puts it up in smaller quantities for home brewers). It seems to be about 4 N which should be pretty safe to handle.

 

[Enda]

Hi guys,

Sorry to revive such an old thread again, but I have soon more information. I had two water reports done on the above water, one sample had been boiled and left over night and the other sample had phosphoric acid, calcium chloride and gypsum added to mash in levels. The one reading that baffles me a little is the total alkalinity value in the water with the added salts, it is negative 2.0mg/l. In the boiled water it is, 92.4mg/l. I would have expected the opposite. Everything else looks correct, the report with added salts does has elevated levels of calcium and sulfate, both over 100mg/l and the boiled water has lower levels of calcium 24.6mg/l.

Thanks again.

 

[ajdelange]

When alkalinity is measured the analyst adds acid to a sample of the water in increments while he monitors the pH. This is continued until the pH reaches 4.5 (at most laboratories - i.e. those that use the ISO procedure). The alkalinity is the number of mL of 0.1 N acid which must be added to 0.1 L of sample to reach 5.4. It is a confusing but well established practice to multiply the alkalinity by 50 and report the result as "mg/l (or ppm) as CaCO3". What if the sample is at a pH which is less than 4.5 to start with? The analyst must then add negative acid (a base such as sodium hydroxide) to increase the pH to 4.5. That is clearly what has happened here and means that you have added as much phosphoric acid to your water as the analyst would in doing the alkalinity test plus a bit more.

As for the boiled water: you started with about 4 mEq/L (200 ppm) alkalinity and about 3 mEq/L calcium. Boiling will drop the smaller of these (the calcium in this case) to around 1 taking out (in this case) 2 mEq/L of calcium and 2 mEq/L alkalinity leaving 2 or 100 ppm. All seems normal.

 

[Enda]

Great thank you so much, good to know acid additions throw off total alkalinity measurements. I really feel like I am getting a hold on this water profile.