Brewing dark beers with soft water, Critique!

[QC_Brew]

Hey Guys,

Long time lurker. First time poster. Been toying with some water adjustments for the past 5 batches or so. My tap water is soft, practically distilled water. Got my ward labs report back a few months ago and here's what I'm dealing with.

Ca 12
Na 5
Mg 2
CaCO3 38
SO4 12
Cl 8
CO3 < 1
HCO3 24
Total Alkalinity CACO3 21

pH 8.8

Im brewing an Oatmeal Stout on saturday that I pulled off this forum.

Im worried about the mash pH getting too low with the roasted grains and my water. Im doing a 5 gal batch and for roasted grains im using .75 lbs roasted barley, .75 pale chocolate, and .5 lbs Crystal 80. Using Bru'n water's black balanced water profile, I added 1 g Gypsum, 1g CaCl and 1 g of baking soda. I know everyone hates on baking soda but under 100ppm most references say its ok and ive used it in brews in the past and had no detrimental effects.

My anticipated mash pH on Bru'n water says 5.3. That seems good to me but the numbers just dont make sense to me. Do you think I just add some more buffering capacity to get it up closer to 5.4 or 5.5? 1g of baking soda seems like nothing. The adjusted RA says its only 31, but all I care about is the mash pH being where it needs to be, right?

This is my finished water profile so far.

Ca 52
Mg 2
Na 27
Sulfate 56
Chloride 46
Bicarbonate 83
Hardness as CACO3 138
expected mash pH 5.3

Looking for a balanced beer leaning a bit toward the malty side, and not grainy and astringent. Also was thinking of mashing a bit thinner maybe 1.4 or 1.5 to keep the pH in check.

Thanks guys!

 

[ChillWill]

I'd up the bicarb and CaCl2 if I were you. My water isn't a million miles of what you've got there and without more of those two, I was getting astringency issues, most likely from pH raising too much throughout the sparge due to low buffering.

pH 5.3 is fine for the mash, I wouldn't worry about changing your mash liquor amount.

 

[mchrispen]

As a counterpoint, I like to mash higher, around 5.5 for darker malty beers. At the recommendation of a friend, I adjusted a dark porter with baking soda, and it really made the malts and roasts pop a bit more. YMMV, but I would up the baking soda a bit - you have some room there. Obviously, don't add bicarbonate to the sparge...

And yes, ignore RA, unless you are comparing this water build to another. Mash pH is more critical.

 

[mabrungard]

This is my finished water profile so far.

Ca 52
Mg 2
Na 27
Sulfate 56
Chloride 46
Bicarbonate 83
Hardness as CACO3 138
expected mash pH 5.3

Which version of Bru'n Water were the concentrations calculated with? If its the free version, then the final concentrations in the kettle would be lower since the sparging water dilutes the sodium content since baking soda is not a component in sparging water. The supporters version does report the diluted concentrations in the kettle so that you will know better what the effect on flavor will be. Even with that, I find that sodium is actually pretty nice in dark styles. Also as Matt mentions, bumping the mash pH up a little bit more does seem to mellow the roast flavors.

 

[QC_Brew]

Which version of Bru'n Water were the concentrations calculated with? If its the free version, then the final concentrations in the kettle would be lower since the sparging water dilutes the sodium content since baking soda is not a component in sparging water. The supporters version does report the diluted concentrations in the kettle so that you will know better what the effect on flavor will be. Even with that, I find that sodium is actually pretty nice in dark styles. Also as Matt mentions, bumping the mash pH up a little bit more does seem to mellow the roast flavors.

Yeah it was the free version. Didn't even think about the sparge water diluting the Na levels. I agree about having a little sodium in darker styles. At what levels do you think the Na starts to impart unwanted characteristics? I'd definitely like to keep it under 100ppm. That's for the input, I'm gonna toy with the levels tonight and get it up closer to 5.4 or 5.5.

I don't think I'm gonna acidify the sparge I'm guessing the grain bed win have enough acidity to keep my pH from going too high in the sparge.

 

[mabrungard]

While not very exact, if you are sparging with roughly the same volume as your mashing water, then the sodium concentration would be about half what it was calculated for in the mash. So you could go much higher and bank on the dilution correcting the sodium content of the overall wort.

With your tap water, sparge water acidification is not required and it will only take a few drops anyhow. The alkalinity is already low enough in the tap water. At 25 ppm sodium, I doubt anyone could taste a difference. At 50 ppm, they might. At 100 ppm sodium, most people are going to note a difference, but the wort flavor won't be 'salty'. It should be sweeter and fuller.

So for your mash, I would add baking soda as needed to reach 5.4 to 5.5. I'm doubting that the mash sodium content would need to be over 60 or 70 ppm and that would end up diluted to something much lower with the sparging water. Don't worry too much about sodium in this case.

 

[QC_Brew]

thanks for the input. bumped up the baking soda a little. Heres my finished water profile now:

Ca 52
Mg 2
Na 56
Sulfate 56
Chloride 46
Bicarbonate 150

expected mash pH 5.5
Hardness as CACO3 138


RA makes a little more sense now being close to 90 for a 32 SRM beer. It must be tough to brew a dark beer starting with RO water. What else have you guys used to add alkalinity? Ive read chalk isnt very soluble/efficient just thrown in the mash that you can bubble co2 to help dissolve it. Seems like a lot of extra work. Slaked lime the only other option?

 

[ajdelange]

It's usually not necessary to add alkalinity to RO water unless the beer you are brewing is really heavy laden with dark malts in which case there is probably too much dark malt for my taste but recognizing that some people like that sodium bicarbonate or sodium carbonate are probably the best things to use. Even simpler is to get some alkalinity by blending in a portion of your tap water assuming your tap water has the alkalinity unencumbered by something else you don't want.

The dark beers are tough in that to get an accurate prediction of mash pH you need to know the details of the particular malts you are using which is added to the uncertainties with the base malts. I have detailed data on only a few malts which may or may not bear close resemblance to those you plan to use but I pushed a few numbers around anyway which may be of value from the perspective they lend. I used 80L Briess, Briess Roast Barley and 600L Crisp chocolate for the specialty malts. I assume that these together, in the amounts you specified, make up 20% of the grain bill and the rest (8 lbs) is Maris Otter. Assuming that to be Crisps M.O. I'd estimate a DI water mash pH of 5.43. Switching to Munton's would raise that pH to 5.54. These are both as measured at room temperature and as you can see the choice of maltster alone in the case makes an appreciable difference. To complicate things further note that these two maltster's products differ appreciably in their room temperature DI mash pH's but not so much in their mash temperature pH's.

Adding a gram of sodium bicarbonate (I'm assuming 4 gal mash water) would get the pH estimate up to 5.58 in the case of Muntons and 5.47 in the case of Crisp and add only 18.2 mg/L sodium.

The real conclusion here is that doing dark beers, assuming that you really want to be in control of mash pH, is where you really need to use a pH meter either with test mashes or by careful monitoring of real mashes or both.

 

[QC_Brew]

It's usually not necessary to add alkalinity to RO water unless the beer you are brewing is really heavy laden with dark malts in which case there is probably too much dark malt for my taste but recognizing that some people like that sodium bicarbonate or sodium carbonate are probably the best things to use. Even simpler is to get some alkalinity by blending in a portion of your tap water assuming your tap water has the alkalinity unencumbered by something else you don't want.

The dark beers are tough in that to get an accurate prediction of mash pH you need to know the details of the particular malts you are using which is added to the uncertainties with the base malts. I have detailed data on only a few malts which may or may not bear close resemblance to those you plan to use but I pushed a few numbers around anyway which may be of value from the perspective they lend. I used 80L Briess, Briess Roast Barley and 600L Crisp chocolate for the specialty malts. I assume that these together, in the amounts you specified, make up 20% of the grain bill and the rest (8 lbs) is Maris Otter. Assuming that to be Crisps M.O. I'd estimate a DI water mash pH of 5.43. Switching to Munton's would raise that pH to 5.54. These are both as measured at room temperature and as you can see the choice of maltster alone in the case makes an appreciable difference. To complicate things further note that these two maltster's products differ appreciably in their room temperature DI mash pH's but not so much in their mash temperature pH's.

Adding a gram of sodium bicarbonate (I'm assuming 4 gal mash water) would get the pH estimate up to 5.58 in the case of Muntons and 5.47 in the case of Crisp and add only 18.2 mg/L sodium.

The real conclusion here is that doing dark beers, assuming that you really want to be in control of mash pH, is where you really need to use a pH meter either with test mashes or by careful monitoring of real mashes or both.

I should have included the recipe in the original post. Its a pull from Yoopers Oatmeal Stout. You're spot on with 20% roast malts. Im not sure but I think my brew shop using briess malts for most. I would have to ask next time I go. I know for sure the 2 row is briess.

7lbs 2 row (briess) 62.2%
1 lb flaked oats 8.8%
0.5 lb flaked barley 4.4%
0.75 lb American roasted barley 6.67%
0.75 lb Victory 6.6%
0.75 lb Fawcett Pale Choc 6.67%
0.5 lb Crystal 80 4.44%


I'm mashing with 3.7 gallons (11.25 total grain bill) giving me a 1.3 water to grist ratio aiming for a 5.25 batch with a 6.5 gal boil. To get me to an expected mash pH of 5.5 Bru'n water says I would need to add 2.4g of baking soda in the mash which brings my Na levels up to 52. (which should be diluted due to 5 gal sparge?) I did 0.3 g/gallon Gypsum 0.65g/gallon baking soda and 0.3g/gallon of CaCl.

What is your opinion about adding Gypsum and CaCl into the kettle rather than the mash to help keep the pH up higher? If I pull those two from the mash it bumps me up 0.1 to expected 5.6 mash pH. Do you think that makes an appeciable difference? Mashing thinner (more water to grist) also helps keep the pH up higher is my understanding. Is there a point where it would become too thin? I'm leaving it at 1.3 for now.

You're right I do need to pony up and get a pH meter. Been looking into the milwaukee mw102. Any experience with that meter?

 

[mchrispen]

I have that meter and love it. Watch the care and storage on the probe and it will serve you well.

Your recipe and the little amount of baking soda spec'd is precisely how I would brew this, and use the normal process with the minerals in the mash and sparge waters. Clearly the meter would help you nail the mash pH, but in the lack of it - you are asking the right questions. Brew it that way... Take careful notes.... Brew again with more or less to compare.