Missed Mash pH on last three brews

[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!