Missed Mash pH on last three brews

[tracer bullet]

I've always done 3-point. I can switch to 2-point.

Something I do, and maybe this isn't great, is do a full calibration just only occasionally. After that I do use the solutions each time but I don't calibrate, I just sanity check. I dunk the probe into 4.00 and look for 4.00, then (after a DI rinse) dunk it in 7.00 and look for 7.00. If I'm at those numbers, or super close, I check my wort pH next. I don't mess with the calibration function at all if I have liked what I've seen. If you are actually calibrating each time, that could be part of the problem? Something gone awry there.

Definitely a fan of checking with another meter at the same time.

Save the wort for a while too, a half cup worth or something, to fiddle with later. Might be a bit too much to take on during brew day, don't let the meter fun accidentally mess up a batch of beer..

 

[SanPancho]

Yeah, but I'm using direct lab tests from samples at my house, not EBMUD water reports. Certainly there are differences when they switch reservoirs, but I don't think big enough to cause this.

oh man, those numbers are way off. No, that’s not just water quality. But to be clear we were at 8-9 grains hardness in 2021 (avg). It’s not gotten better, and that’s already at medium, not soft.

but given what you’re saying I’d just replace the probe. They will go bad, even stored properly. its frustrating.

and email your lab report to ebmud, ask them to compare vs the oct avg readings For San Leandro reservoir. you’ll feel a little better.

 

[natmartin]

oh man, those numbers are way off. No, that’s not just water quality. But to be clear we were at 8-9 grains hardness in 2021 (avg). It’s not gotten better, and that’s already at medium, not soft.

but given what you’re saying I’d just replace the probe. They will go bad, even stored properly. its frustrating.

and email your lab report to ebmud, ask them to compare vs the oct avg readings For San Leandro reservoir. you’ll feel a little better.

I'll email them. Are you saying basically that the average water is sticking pretty close to what I've measured?
Yeah, I'm definitely suspecting the probe. But man, I just bought it in February. Isn't that quick for it to go bad?

 

[dmtaylor]

Yeah, I'm definitely suspecting the probe. But man, I just bought it in February. Isn't that quick for it to go bad?

Yes. But unfortunately it is possible.

Meanwhile, my cheap $10 Chinese pH meter still works fine after about 5 years.

 

[CleanEmUpIves]

The Thermoworks 8689 doesn't have great reviews. Use a Milwaukee MW102 myself.

Meanwhile, my cheap $10 Chinese pH meter still works fine after about 5 years.

Is that the one you stick directly in the mash?

 

[dmtaylor]

Is that the one you stick directly in the mash?

One and the same.

 

[CleanEmUpIves]

One and the same.

Well, fame comes at a price. Now what was that pH offset at mash vs room temp... I jest... I jest...

 

[IslandLizard]

As long as your probe calibrates (2-point is adequate for mash range) and keeps its calibration (or close to it when verified) over a few days it's likely just fine.
When it drifts during calibration and doesn't keep calibration for any length of time, it probably needs cleaning (in HCl) or replaced. Proteins (from the mash) can really gum up the bulb.

You seem to be consistently 0.6 pH points higher than calculated...
I therefore suspect your water is quite a bit harder/more alkaline than its (recent) tests show.
You can titrate it to get an idea of the actual alkalinity.
Or do small test mashes with 8-16 oz of your grist mixes. Stick em in a small lidded pot in a pre-warmed but turned off oven to keep it close to mash temps.

Another thought, is your lactic acid indeed at 88%?
I'd say it is, given your Porter (without an acid addition) is also 0.6 pH high.

 

[natmartin]

As long as your probe calibrates (2-point is adequate for mash range) and keeps its calibration (or close to it when verified) over a few days it's likely just fine.
When it drifts during calibration and doesn't keep calibration for any length of time, it probably needs cleaning (in HCl) or replaced. Proteins (from the mash) can really gum up the bulb.

You seem to be consistently 0.6 pH points higher than calculated...
I therefore suspect your water is quite a bit harder/more alkaline than its (recent) tests show.
You can titrate it to get an idea of the actual alkalinity.
Or do small test mashes with 8-16 oz of your grist mixes. Stick em in a small lidded pot in a pre-warmed but turned off oven to keep it close to mash temps.

Another thought, is your lactic acid indeed at 88%?
I'd say it is, given your Porter (without an acid addition) is also 0.6 pH high.

Are there any resources I can look at to see how to titrate the water and test the alkalinity? (I assume this is what the brew lab kit does? But there might be other more precise methods?)

 

[SanPancho]

I'll email them. Are you saying basically that the average water is sticking pretty close to what I've measured?
Yeah, I'm definitely suspecting the probe. But man, I just bought it in February. Isn't that quick for it to go bad?

ive had them go bad in under a year for sure.

your water report doesnt seem similar to ebmud figures (for us). san leandro range for alkalinity is 97-160. hardness is 100-160. thats for all of 2021. now look at 2022 data jan thru jun, we get 100 for alkalinity and 94-100 for hardness. your alkalinity/hardness (assuming ppm as caco3) in your report is out of range. for 2021 and for beginning 2022.

we get sierra water once snows hit and then melt. call it jan to june/july. but july to dec/jan is mostly reservoir and wells, thats when we see the 160s instead of 100s. and considering drought hasnt eased i think we're gonna get even lower proportion of sierra water going forward. (apparently we also pulled water from sacto river last year due to drought, only 2nd time in history)

i just dont see how you could get 50ppm alkalinity unless it was a fluke. say a temporary shutdown of san leandro and we got orinda water for a while. its possible, just seems very very different vs what they report for us. im no expert on their system, but the numbers just seem way off you know?

oddly enough, i was literally going to post a question today as to whether its worth "treating" our water for hardness, given how im now doing lagers in medium hardness vs my formerly soft water (the city).

in any case, its worth asking ebmud. if you have your sample date they should be able to tell if there were any system changes at the time.

also, heres first thing you see on their water quality reports page--

EBMUD Water Operations Update​

EBMUD makes adjustments to the way we operate our vast system for reasons including infrastructure improvements, seasonal changes, drought response, and shifting water demands from customers. In all cases, the water that reaches customer taps meets or exceeds all standards for safe drinking water.

Most of EBMUD’s water supply comes from Pardee Reservoir about 90 miles east of our service area. Because of the drought, however, we are relying more heavily on local reservoirs compared to a typical year. This locally stored water has more minerals, making it taste more salty. In addition. the water from east bay reservoirs can be affected by algae blooms which give the water an earthy or musty taste and odor. Both the Sobrante and Upper San Leandro Water Treatment Plants treat water from these local reservoirs. Their ozonation systems are designed to remove these smelly compounds but not the minerals. Regardless of the treatment plant in service, all customers receive high-quality drinking water.

Lower water levels visible at USL Reservoir: Hikers along Upper San Leandro Reservoir may notice lower supply levels as EBMUD uses this local reservoir to supply more water than usual to accommodate various construction projects in our water system. In addition, EBMUD is also managing our water supply during the drought. Our intent is to refill USL later in the fall.

 

[SanPancho]

Yes. But unfortunately it is possible.

Meanwhile, my cheap $10 Chinese pH meter still works fine after about 5 years.

im very seriously contemplating going back to those. dont need precision, just wanna make sure im in the ballpark you know?

 

[natmartin]

Might be time for me to consider getting an RO system, so I don’t have to worry about the changing water.

@SanPancho ill send you some of my water data from throughout the year on the BAM slack, see how it matches up with what you’re seeing.

 

[IslandLizard]

Are there any resources I can look at to see how to titrate the water and test the alkalinity? (I assume this is what the brew lab kit does? But there might be other more precise methods?)

There must be plenty of resources for titration, without elaborate lab equipment and $$ titration solutions.

Since you have a pH meter, it's rather simple to check/correct your small test mash.* Add acid dropwise until it hits your intended pH target. Add a proportional amount to your calculated acid needs.

For starters, I guess you could tweak your alkalinity value in your brewing water calculator until you hit the currently measured (and too high) mash pH. That will raise your acid demand, bringing your actual mash pH to a much closer value.

* AJ (DeLange) has always said to test your mash pH at the end of the mash, when it's done.

 

[SanPancho]

Might be time for me to consider getting an RO system, so I don’t have to worry about the changing water.

@SanPancho ill send you some of my water data from throughout the year on the BAM slack, see how it matches up with what you’re seeing.

Folks I bought my place from had a small ro system in bsmt. Probably needs new filters but you’re welcome to it. Has two storage tanks.

 

[natmartin]

Folks I bought my place from had a small ro system in bsmt. Probably needs new filters but you’re welcome to it. Has two storage tanks.

That's amazing, I'll DM you!

 

[natmartin]

Ok, I brewed this weekend, so here's an update. Still some mysteries here.

I brewed a Cold IPA again, though I changed up the recipe a bit.

I also rechecked my water the night before with the brewlab kit, using a sample of the actual water filling my system. My water is even softer now than it was earlier in the summer:

Total Hardness as CaCO3: 10ppm
Calcium: 4ppm
Magnesium: 0ppm
Chloride: 20ppm
Sulfate: 0ppm (or lat least less than 25ppm, the brewlab doesn't resolve this low)
Total Alkalinity as CaCO3: 20ppm
Bicarbonate (HCO3): 24ppm
Residual Alkalinity: 17ppm
Sodium: 18ppm
pH: 6.66

I hadn't brewed in 2 months. So I checked the calibration of my Thermoworks. It had drifted a lot, so I recalibrated it.

I also checked my old Milwaukee MW102, which I hadn't used in years. Surprisingly, it didn't drift too far off, but I recalibrated it anyway.

In the morning, I checked both meters with my calibration solutions again. The Thermoworks was about .1 low. The MW102 was perfect at 4pH, and about .05low at 7pH.

Grist:

• 10lb Great Wester Superior Pils
• 3.33lb Sugar Creek White Malted Corn
• 8oz Whole Cone Cascade Hops (mash hops)

27.25L strike water

Mineral Additions:

• Aiming for 175ppm Sulfate / 100ppm Chloride
• Gypsum: 5.56g
• Epsom Salt: 3.68g
• Calcium Chloride: 27.64g (liquid solution, 1.12SG)
• 1.07g Brewtan-B (I used this in the previous batches too, I forgot to mention that earlier.)

I aimed for 5.3pH. Because my water is so soft, Bru'n Water showed that I didn't need very much. Either 1.19mL of 88% Lactic, or 13.28mL of 10% Phosphoric. I chose to use the Phosphoric, since that would be easier to measure out.

I intended to use both pH meters as a comparison, but at first the MW102 stopped booting reliably. I fixed it eventually, but I couldn't use it for the first two datapoints.

10 minutes: ~5.8*
20 minutes: ~5.8*
30 minutes: I got the MW102 working again, and it showed 5.45. I stopped using the Thermoworks at this point, since it was so far off.
40 minutes: 5.62
At this point, I added an additional 2mL of phosphoric acid
50 minutes: 5.68
Added another 2mL of phosphoric acid
60 minutes: 5.55
Added another 3mL of phosphoric acid
70 minutes: 5.57
Added another 3mL of phosphoric acid
80 minutes: 5.59
Added another 3mL of phosphoric acid
90 minutes: 5.55

... and it stayed hovering around 5.55 for the rest of the mash, ending at 5.46
Note: This mash was *slow* too. It was a step mash, so I was planning on around 90 minutes, but it ended up taking 3 hours to fully convert!

Final post-boil chilled sample was 5.3pH

One experiment I did: I took one of my samples that was measuring 5.55, and added one drop of acid to it. The pH immediately dropped to 5.1

Some conclusions and questions:

1. The acid is acting like an acid, since it dropped the pH of the sample.
2. The thermoworks pH meter is crap, but there's still something weird going on.
3. At least my pH was in an acceptable range, but it still wasn't what I was intending.
4. Why didn't the mash pH change even as I added an additional 13mL of acid, twice as much as calculated?
5. Could the mash hops have any influence?
6. Could the brewtan-b have any influence?
7. Could my extra-long mash length be related?
   1. Looking through my notes, it looks like all three batches that had the pH issues also had very long mashes.
   2. The previous batches converted much quicker
8. I need to check my notes, but I might have tightened the gap on my mill around the same time that these pH problems started. Could that be related? Grasping at straws now.

 

[Silver_Is_Money]

With my 'Mash Made Easy' software set to it's as downloaded defaults the prediction is that for the recipe seen immediately above in post #46 the mash pH without any acid addition should be ~5.69, and that 38.8 mL of 10% Phosphoric Acid would be required to bring the mash to approximately pH 5.40.

 

[CleanEmUpIves]

Mash pH prediction software works for those that don't measure mash pH or those that have the DI pH of each malt in the grist and use a proton deficit model.

What was your test mash pH?

 

[natmartin]

With my 'Mash Made Easy' software set to it's as downloaded defaults the prediction is that for the recipe seen immediately above in post #46 the mash pH without any acid addition should be ~5.69, and that 38.8 mL of 10% Phosphoric Acid would be required to bring the mash to approximately pH 5.40.

Sounds like I should check out your software.
I’m curious, what are you doing differently from Bru’n Water, since the results are ending up fairly different?

 

[Silver_Is_Money]

Sounds like I should check out your software.
I’m curious, what are you doing differently from Bru’n Water, since the results are ending up fairly different?

No idea, as Bru'n Water (as for MME) is not open to snooping whereby to see what makes it tick. But one difference is that on this and (perhaps even more so) the sister Brewer's Friend site I've detailed much (close to all, if not factually all) of the inner workings of MME. Enough has been finely detailed such that anyone should be capable of generating their own respectable mash prediction software from my methodology. And from private feedback on the BF site I know of one person who has done just that. As my software is free and not merely a teaser leading to a pay version, and is therefore fully complete, and is nerver going to become a teaser leading to a pay version, I eventually decided to detail what makes it tick.

 

[natmartin]

No idea, as Bru'n Water (as for MME) is not open to snooping whereby to see what makes it tick. But one difference is that on this and (perhaps even more so) the sister Brewer's Friend site I've detailed much (close to all, if not factually all) of the inner workings of MME. Enough has been finely detailed such that anyone should be capable of generating their own respectable mash prediction software from my methodology. And from private feedback on the BF site I know of one person who has done just that. As my software is free and not merely a teaser leading to a pay version, and is therefore fully complete, and is nerver going to become a teaser leading to a pay version, I eventually decided to detail what makes it tick.

Wow, I think I'm switching over! Using your program, with 13mL of Phosphoric acid added, it's predicting 5.59. I saw around 5.62-5.68

Adding another 13mL, it predicts 5.50. I saw 5.55.

I'll try using your application to plan my next batch. Thanks!