Strange PH estimate for Porter Recipe w/London Water

[rikki_bobbi]

Hi all,

A relative newcomer to home brewing here with about 10 all-grain brews under my belt so far but all in the pale / bitter / IPA category despite living in Central London where the water was historically perfect for porters. I've been using brewer's friend along with tap water with a known water report to calculate my water chemistry with pale beers so far and, dialling in with acid malt in the grist, I'm getting close to my desired PH every time.

I've decided to have a crack at an India Porter loosely based on The Kernel's Export India Porter or at least Malt Miller's version of it from the grain bill they list.

I didn't want to end up making a Black IPA so I've added some Roasted Barley to the recipe (do feel free to mock me if this sounds awful) and intending to use more traditional English varieties (likely Target for bittering and Phoenix for flavour/aroma on the first batch) rather than citrus forward American varieties.

Having punched my local water report for notoriously hard water with a ph of 7.62 into Brewer's Friend's mash chemistry calculator, I'm getting a PH estimate of 3.22 based off of my grain bill!?? I know the grain bill would lower the PH a fair bit but that seems utterly ridiculous.

Water profile and grain bill are detailed here: Mash Chemistry and Brewing Water Calculator - Brewer's Friend

India Porter

12.5l Batch
OG: 1.064
IBU: 50

2.48kg Maris Otter
231g Brown Malt
231g Crystal 90
231g Chocolate
112g Roasted Barley
112g Black Patent
112g Flaked Oats






Am I going crazy?

 

[rikki_bobbi]

I think I might have sussed it... speciality malt or roasted malt? Hmmm

 

[Silver_Is_Money]

Bingo! Switch all of the specialty to roasted.

 

[CascadesBrewer]

I think I might have sussed it... speciality malt or roasted malt? Hmmm

I don't use Brewer's Friend myself, but I have to wonder what the difference between a Roasted Malt and a Specialty Malt is...and why swapping them to Specialty Malt drop the pH prediction down from 5.35 to 2.43!!

Also, I suspect you are not adding 0.231 grams of Brown Malt.

 

[dmtaylor]

When I corrected the units on the brown malt from g to kg and changed all the roasted malts to roasted malts, I got 5.22 which makes a whole lot more sense:

 

[DuncB]

I agree same after those adjustments, but did note that it wanted you to add 0.23 ml of lactic acid to hit the 5.2 pH target. I wouldn't bother with this as 5.22 is definitely close enough.

 

[dmtaylor]

I agree same after those adjustments, but did note that it wanted you to add 0.23 ml of lactic acid to hit the 5.2 pH target. I wouldn't bother with this as 5.22 is definitely close enough.

Ditto. I would never acidify a porter or stout or other black beer. If anything, I'd consider adding 1/4 teaspoon or so of baking soda to bring the pH up closer to say 5.4. The black malts have acidifying power on their own.

 

[DuncB]

Looks like 1g of bicarb would bring pH to 5.4 and the sodium up to 50 .

 

[rikki_bobbi]

Thanks guys. A DOH! and EUREKA moment all rolled into one.

I'm not quite sure what brewers friend considers to be a 'speciality' malt then but I'll give it a go and see where my numbers come out.

Quite looking forward to seeing what 2021's Thames Water can do in my first dark beer.

 

[Silver_Is_Money]

Unless I'm not looking at it correctly, I've just noticed that the water analysis as seen on Brewer's Friend for this Porter is totally out of wack as to its cation and anion milliequivalents balance. This throws a huge monkey-wrench into the works. This water analysis is blatantly impossible.

 

[Silver_Is_Money]

I'm not quite sure what brewers friend considers to be a 'specialty' malt then but I'll give it a go and see where my numbers come out.

My best guess is that malts like Biscuit, Amber, Melanoidin, Honey, Victory, and Aromatic would be likely candidates for the specialty malts category. Possibly also Munich.

 

[rikki_bobbi]

Thanks for the heads up! I must admit a lot of this is still guesswork for me and I wish I had the slightest understanding of what you're referring to but it's based on this water report from Thames if you're curious: DownloadWQ_Report_Z0095_East_Lambeth.pdf

For my last 6 or so brews I had been using bottled spring water that gives a very simple mineral breakdown but these detailed water reports make my brain hurt.

 

[DuncB]

It does mention slaked lime in a sub menu for boiling and lime softening, not sure if it expects this to be added in its' calculations.
I never look at that when I've used BF for my water.

 

[DuncB]

I've just been and had a look at a recent water profile on BF that I used and have checked the sub menu for boiling and lime softening and that is suggesting 0.4g of slaked lime for me.
Have I been missing something in all of my water profiles that I've made up?

 

[dmtaylor]

Slaked lime a.k.a. pickling lime will raise pH and calcium with no real flavor impact. You already have tons of calcium but low sodium which is why I suggested baking soda instead which also raises pH. Either one could help, IF you believe a mash pH of 5.22 might be too low. Like I said, I personally would aim for more like 5.4. But 5.2 still makes good beer as well.

 

[Silver_Is_Money]

Have I been missing something in all of my water profiles that I've made up?

That depends upon what you mean by "made up". Cations and Anions must be in balance for real water. Otherwise you might (literally) be in for a big shock. Apparently BF does not check for cation/anion balance.

 

[mabrungard]

The OPs London water is NOT what was used to brew porters. Those Porter breweries got their water from the chalk aquifer under London. As you might surmise, that is much more alkaline. But it’s not as hard as you might expect. It also contained a bit more sodium and chloride that helps the flavor of porters.

Due to contamination in that aquifer, there is little pumping from that aquifer now.

 

[DuncB]

That depends upon what you mean by "made up". Cations and Anions must be in balance for real water. Otherwise you might (literally) be in for a big shock. Apparently BF does not check for cation/anion balance.

What I really mean is does the BF profile expect me to add the slaked lime? as well as the other brewing salts.
I haven't been as I thought that the salts profile I made was all I needed, I didn't know about this slaked lime " addition " or option.

 

[Silver_Is_Money]

What I really mean is does the BF profile expect me to add the slaked lime? as well as the other brewing salts.
I haven't been as I thought that the salts profile I made was all I needed, I didn't know about this slaked lime " addition " or option.

I don't believe BF expects you to do/add anything. All inputs are up to you and at your discretion.

As mentioned above, please check your source water analyticals. Your water as you have entered it has impossible analyticals.

 

[DuncB]

I don't believe BF expects you to do/add anything. All inputs are up to you and at your discretion.

As mentioned above, please check your source water analyticals. Your water as you have entered it has impossible analyticals.

The water profile is the OP one. I just noticed the Slaked lime in the sub menu for the OPs water and found that it was also in a BF water profile I'd made for a different beer.

My base water pretty good here?

Am I missing out something crucial by not adding this slaked lime? I realise it raises pH and calcium but didn't know it has factored in this addition ( unknown to me).

 

[Silver_Is_Money]

Thanks for the heads up! I must admit a lot of this is still guesswork for me and I wish I had the slightest understanding of what you're referring to but it's based on this water report from Thames if you're curious: DownloadWQ_Report_Z0095_East_Lambeth.pdf

For my last 6 or so brews I had been using bottled spring water that gives a very simple mineral breakdown but these detailed water reports make my brain hurt.

Your Ca++ (Calcium ion, or Ca) is only about 90-100 mg/L (and likely closer to 90 mg/L on average). Your total hardness of 269 mg/L is not your calcium value.

Also, your values as given by your water authority are averaged from highs and lows, and that is in itself often enough quite problematic with regard to achieving cation/anion balance.

All positive electrical charges and negative electrical charges within water must always sum to a net of zero. Thus the positively charged mineral ions and negatively charged mineral ions must be in milliEquivalent per Liter (mEq/L) balance or harmony. With calcium at around 90 mg/L this balance looks reasonable.

 

[DuncB]

Your Ca++ (Calcium ion, or Ca) is only about 90-100 mg/L (and likely closer to 90 mg/L on average). Your total hardness of 269 mg/L is not your calcium value.

Also, your values as given by your water authority are averaged from highs and lows, and that is in itself often enough quite problematic with regard to achieving cation/anion balance.

All positive electrical charges and negative electrical charges within water must always sum to a net of zero. Thus the positively charged mineral ions and negatively charged mineral ions must be in milliequivalent balance or harmony. With calcium at around 90 mg/L this balance looks reasonable.

That's interesting because with your suggested change to around 90mg/L of Ca2+ the water profile that rikki_bobbi has is actually very close to the water details of the London porter water profile without any adjustment at all.

 

[Silver_Is_Money]

Ca++, Mg++, Na+, and K+ are the primary cations

Cl-, SO4--, NO3-, and HCO3- (the Bicarbonate ion) are the primary anions

Total Hardness (as CaCO3) ~= 2.5(Ca++) + 4.12(Mg++) (for water that is "real", and not "averaged")

Averaged analyticals do not have a very high probability or likelihood of making "real" water.... (as in water that will exhibit the requisite cation/anion mEq/L balance).

 

[Silver_Is_Money]

There is quite likely no actual 'good faith' effort at a typical main stream "drinkable" beer brewing mash (even if of an amazing robustness as to its content of caramel/crystal and/or deep roasted malts) that has actually taken place and which has yielded a reliable and unquestionable 'room temperature measured' pH reading much below roughly pH 4.8. The lowest pHDI I've ever come across for any single malt was for a lot of an incredibly dark 629 Lovibond Black Malt that weighed in at 4.24 pHDI within a collection of pHDI data forwarded to me by a technician at Briess. It is doubtful that anyone will ever attempt a straight up 100% single malt mash whereby to attain a drinkable beer from a sample of this specific malt (or one similar to it in robustness), so if you ever use software which predicts a mash below say about 4.7 pH (allowing for massive calcium present within the mash water), this would be an extremely good indication that a red flag should immediately be tossed up with regard to user input error (which quite often reflects poor choices as to malt type or class), software error, software deficiency as to malt class choices, or all of these combined.

Another issue is that such software will always be deficient and lacking in a requisite base of mash environment reality, as it will always instead reflect a multiplicity of guesses and presumptions and averages and data cherry picking biases and questionable math models which can only at best hope to reflect some portion of a subset of likely reality. Thus all software for mash pH should rightfully be questioned and even stress tested. This is because, just as in a court of law, there is always the potential for "falsus in uno, falsus in omnibus" to expose serious issues of concern worthy of being questioned. I develop such software, and I can assure you that there are stress tests that my software can't pass. I'm actively running such a stress test on mash pH assistant software in another thread, and it is shocking as to the question marks to outright failures it has uncovered.

And then there is "confirmation bias"....

 

[rikki_bobbi]

The OPs London water is NOT what was used to brew porters. Those Porter breweries got their water from the chalk aquifer under London. As you might surmise, that is much more alkaline. But it’s not as hard as you might expect. It also contained a bit more sodium and chloride that helps the flavor of porters.

Due to contamination in that aquifer, there is little pumping from that aquifer now.

I was of this understanding aswell. I have heard suggestions that a lot of the water here is sourced from Surrey somewhere but I couldn't say for sure. All I know is that it is very hard.

I went for the brew anyway and, with absolutely no water additions or filtering, my mash ph 10 mins in was 5.58

 

[DuncB]

Thanks for update, await the next info.

 

[Silver_Is_Money]

I was of this understanding aswell. I have heard suggestions that a lot of the water here is sourced from Surrey somewhere but I couldn't say for sure. All I know is that it is very hard.

I went for the brew anyway and, with absolutely no water additions or filtering, my mash ph 10 mins in was 5.58

This supports the contention that the downward pH shift projected/anticipated for calcium and magnesium is not nearly what most software presumes for it. But I do feel that if you had allowed for more than 10 minutes before pulling the sample, that this would have allowed more time for the water to fully permeate the acidic malt kernels and liberate their acidity, whereby lowering the pH a bit more than the 5.58 pH which you measured early, and in the presence of 187 ppm Alkalinity water.