Mash pH Bru'n Water vs Brewers Friend

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underdog378

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Hey all,
Brewing today and having issues with mash pH. Ive been using supporters version of bru'nwater for building up my water from scratch (RO Water) and my pH is consistently off, especially when acid additions are involved. Today I'm brewing a Kolsch. I added all my calcium chloride to the mash, 6.23grams, 6 gallons of strike water. Grain bill is as follows (11 gallon batch):

16.25lbs Weyermann Pils
1lb Vienna Malt
.5lb Wheat Malt

With 6.23grams of Calcium Chloride and 1ml of 88% Lactic Acid my estimated mash pH in bru'nwater is 5.34. Great!

Unfortunately all was not great. About 10 minutes into the mash I took a sample, cooled to room temp and took a mash pH reading (with calibrated ph meter)of.....5.75 :(

I added more lactic acid at this point until the pH was approximately 5.4 at room temp and called it good at this point. Total acid I needed to add was 5.4mL and that is a huge difference from the calculation and with that amount of lactic acid bru'n water says I should be down around 4.97.

Frustrated I input all the same information into brewers friend's mash ph calculator and with 5.4mL of 88% Lactic Acid solution the estimated mash ph is....5.4! Which is exactly what I ended up getting with that amount of lactic acid.

So obviously Bru'n Water is accounting for far more change in pH with the lactic acid addition than Brewers Friend is, and Brewers Friend was spot on for me while Bru'n Water had me frantic. Are these programs calculating acid additions differently? And since I didn't get the mash pH down into the proper range until about 15-20 minutes in do you think I'll have issues with conversion?
 

Jimbodaman

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I can only speak for brewers friend since that's the only one I've used and it has always predicted within a reasonable range, if it's calculated 5.4 it's 5.33-5.48, which is good enough for me, but that's only 4 brews perhaps that might change.
 
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underdog378

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I should note that when it comes to the calculations without acid additions both seem to be close, within .1 maybe .2 at max. But once you dive into acid additions the two are so far apart as to how much lactic acid is needed to get the pH you're looking for and when using Bru'n Water acid addition calculations I have never been close on the pH. This is the first batch where I checked with another calculator and noticed brewersfriend asking for much more acid than Bru'n Water and it ended up lining up with the pH readings I got pretty spot on. Just trying to figure out what's going on as I thought I had Bru'n Water figured out and loved the usability of it, but frustrated at the same time because I'm not getting nearly as accurate predictions as other people and I'm building off straight RO water.
 

PartagasD4

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I have found all the mash predictors to be very close 1 time and then be off next. It you take the time to do a mini mash of say 15-20 grams of malt at least it gives you a starting point so you don't hopefully have the surprise you just had. I do it if I can find the time and it helps. I bought a 50lb bag of Rahr 2 row last fall the malt analysis sheet said the malt had a pH of 5.84. That is almost gone and the new bag of Rahr 2 row I just bought last week analysis sheet says that this malt pH is 5.91.
 

PartagasD4

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Oh and I forgot, brunwater was dead on my last brew. It told me 2 ml of lactic would bring the pH to 5.19. Brewersfriend said the pH would be 5.38. brunwater had been off just like you the last couples batch's so I didn't believe it this time, so I added the 2 ml lactic and guess what.... pH after 30 minutes was 5.2. :D
 

The_Bishop

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Could be a few things going on:

Your RO water isn't as RO as you think it is. Check it with a TDS meter and see what the reading is.

The pH Meter is off/not calibrated. What type of meter, when was it last calibrated? Did you use fresh solution to calibrate it? If it's one of those $15 Ebay specials, they work great as a paperweight.

Some kind of data entry error when you entered your brewing info in the spreadsheet?
 
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underdog378

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I'll check the RO Water with a TDS meter. It does come from a grocery store machine but it's high traffic and serviced every week or two.

I do have a cheap pH meter but it's been calibrated with fresh solution and reads within .05 of the listed calibration solution on both the 4.0 and 7.0 solution. I double checked in fresh calibration solution after getting the high reading and verified it was reading 4.04 in the 4.0 solution.

I've gone through the spreadsheet a dozen times and double checked my entries and found nothing. Like I said the estimated pH with just the calcium chloride addition is reasonably close between the two but Bru'n Water shows a massively larger pH change with a much smaller amount of lactic acid when you get into the acid adjustments. The brewersfriend calculator seems to line up with Kai's numbers as far as mL/lb of grain for .1 pH drop but Bru'n Water says that 1/5th of that amount should get me the same drop.
 

ajdelange

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Are these programs calculating acid additions differently?
YES and it is very important that users of them understand that.

For the most part the acid itself is handled in the same way. The strength of the acid varies a little bit depending on the final pH but as the variation in strength is only a couple of percent most of the programs assume that it is 100% (as opposed to the 97 - 99% actual strength). What really varies is the way they model the grains' proton absorbing/emitting characteristics which, as it impractical to take measurements on every batch of malt sold, they must guess at.

There's an old chestnut in the horology biz about the guy who didn't own a watch and so never knew what time it was. So his sister gave him a watch for his birthday and now he knew what time it was. But his other sister on the left coast never talked to the first sister and so she also sent him a watch for Christmas. Now he was back to not knowing what time it was.

It's much the same here. You will get different answers depending on which program you use. Sometimes one is closer than another and sometimes the other is closer. If you find one that tends to match your actual measured pH's better than another use it preferentially for the beer types it checks out for but always verify with a new style that has not been previously verified.
 

h22lude

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YES and it is very important that users of them understand that.

For the most part the acid itself is handled in the same way. The strength of the acid varies a little bit depending on the final pH but as the variation in strength is only a couple of percent most of the programs assume that it is 100% (as opposed to the 97 - 99% actual strength). What really varies is the way they model the grains' proton absorbing/emitting characteristics which, as it impractical to take measurements on every batch of malt sold, they must guess at.

There's an old chestnut in the horology biz about the guy who didn't own a watch and so never knew what time it was. So his sister gave him a watch for his birthday and now he knew what time it was. But his other sister on the left coast never talked to the first sister and so she also sent him a watch for Christmas. Now he was back to not knowing what time it was.

It's much the same here. You will get different answers depending on which program you use. Sometimes one is closer than another and sometimes the other is closer. If you find one that tends to match your actual measured pH's better than another use it preferentially for the beer types it checks out for but always verify with a new style that has not been previously verified.
I like the horology story. That is pretty accurate. I will give another example (personal). I was trying to calibrate my buckets and measuring pitcher. Before trying to calibrate, to me they were both right. I then used the pitcher to calibrate my bucket and the bucket came up short. Now both the pitcher and bucket were wrong because I didn't know if they were both wrong or if one was right I didn't know which one it was.

I like the idea of using both and figuring out which one comes out closer more often. I would assume it would be different for everyone. One person may find Bru'n Water is better while someone else may find Brewers Friend to be better.

Another option is to take the average of the two. Not sure if this would be the best option but it may be better than only using one especially if that calculator is off for your system.
 

mabrungard

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The smart person would recognize that at least one of the data points is off and would take measures to determine which is more correct. Calibration is an important fact of life if you are using allegories to plan your actions.
 

ajdelange

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Another option is to take the average of the two. Not sure if this would be the best option...
It would indeed be the smart thing to do but if, and only if, we knew the errors in both to be purely random (no bias) but we do not know that.

..but it may be better than only using one especially if that calculator is off for your system.
Checking actual mash pH against the programs you use is a way to determine what the bias, if any, may be. Problem is that the bias is likely to be one direction for one group of beers and the other for another.
 
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underdog378

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Your RO water isn't as RO as you think it is. Check it with a TDS meter and see what the reading is.
This made me wonder. The machine I have been getting my water from gets a lot of use and thus serviced pretty regularly. I bought a TDS meter and decided to give it a check...49ppm. Considering the fact that the city water here tests around 60-70 that is basically just straight tap water and probably accounts for my PH issues. (Im on a private well and it tests 70ppm but is high in iron and manganese and tastes horrible so not using it for brewing)

Down the street at a less used water machine and slightly more expensive (albeit same water company) I gave it a test and got a reading of 0ppm.

Brewing tomorrow with the actual RO water and will report my results.

Thanks for the tip and the TDS meter will be a good added tool I use for quick check of my water source. It always seems when I go into something "assuming" I get burned. Lesson learned.
 

ajdelange

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The smart person would recognize that at least one of the data points is off and would take measures to determine which is more correct.

But how do you do that? What do you compare the watches to? Who has the correct time? Einstein's answer to this question was "the man with the clock" (or words to that effect). I was once in a meeting with Gernot Winkler, the Naval Observatory's, and hence the nation's, time keeper. It was, as most meetings are, rather boring and so my wandering mind began to wonder what kind of watch this man would wear. So I dropped a pen in order to be able to bend down to retrieve it while actually looking up his sleeve. The result: he wasn't wearing a watch! When I reported this to a colleague his comment was "Of course he doesn't wear a watch. It is whatever time he says it is!"

Gernot's "clock" was back at the Naval Observatory. You can take your "clock" there to get a 'tick', IOW set it (don't go into the Vice President's entrance though) and when you do they will ask you what kind of time you want. So even they don't know what's right and their times don't agree with UTC.

Calibration is an important fact of life if you are using allegories to plan your actions.
Calibration is important whether you are thinking allegorically or otherwise. That is why I always advise people to use the program that gives them the results that best compare to what they measure with a pH meter for the particular types of beer they are doing. In the time analogy it is the various time scales that lead to the uncertainties. In the pH estimation problem it is the various malt models. There is no way I can tell you which of the several programs best models the particular malt an individual is using for a given brew.
 
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underdog378

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As a follow up, starting with confirmed RO water, after my salt additions Bru'n Water gave me an estimated mash ph of 5.35 and Brewers Friend 5.55. Measured pH came in at 5.54 in this case. Let it ride without chasing it and its at least another data point for my notes.
 

dmr

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I should note that when it comes to the calculations without acid additions both seem to be close, within .1 maybe .2 at max. But once you dive into acid additions the two are so far apart as to how much lactic acid is needed to get the pH you're looking for and when using Bru'n Water acid addition calculations I have never been close on the pH. This is the first batch where I checked with another calculator and noticed brewersfriend asking for much more acid than Bru'n Water and it ended up lining up with the pH readings I got pretty spot on. Just trying to figure out what's going on as I thought I had Bru'n Water figured out and loved the usability of it, but frustrated at the same time because I'm not getting nearly as accurate predictions as other people and I'm building off straight RO water.
If you prefer a spreadsheet rather than an online calculator, you might want to try MpH Water Calculator v3.0, which you can find here. While the model for predicting pH is different than either BrunWater or the Brewer's Friend Calculator, its pH predictions are often quite close to those of the Brewer's Friend Calculator.

Cheers!
 
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