how to adjust mash Ph with lactic acid

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beerisyummy

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Greetings Biermeisters.

I'm sorta ignorant about water chemistry, but trying to learn enough to get by and hopefully be somewhat consistent. Here is what I have been doing.

I tend to go pretty light on the brewing salts. I throw in a little gypsum if I want to accentuate hops, or a little CaCl if I want to accentuate malt. If using, I add to the mash water while heating. I dough in (I BIAB so kettle = mash tun) and after mixing thoroughly I scoop out a sample. I take a pH reading (with a meter) AND THEN GUESS how much Lactic Acid, if any, to toss in to lower the pH.

Usually I'm kinda close, occasionally still too high on the pH by the conclusion of the mash. I would just like to be a little more precise.

I use municipal water run through a carbon filter. If I'm not mistaken my utility water report looks a little on the hard side, but not crazy: avg. Calcium = 15 mg/L, avg Hardness = 70 mg/L, avg pH = 8.5.

Not really interested in buying a bunch of distilled water and adding everything I need/want; not really interested in investing in a water testing kit etc.

Any hope for me?
 
Get a Ward Labs water report of your filtered water. Then, input that into the Brewer's Friend water tool, along with your grain bill. It will tell you exactly how much acid to add to your water. You'll be able to tweak minerals a bit as well.

I know there are other water calcs out there, but that's what works for me.
 
Get a Ward Labs water report of your filtered water. Then, input that into the Brewer's Friend water tool, along with your grain bill. It will tell you exactly how much acid to add to your water. You'll be able to tweak minerals a bit as well.

I know there are other water calcs out there, but that's what works for me.
Thanks, I forgot about Ward Labs. But I wonder if it is really useful because the mineral content of the muni water does fluctuate. It says range detected of Ca is 11 - 26 mg/L and Hardness 52 - 118. So six months later I could be working with different numbers in reality, but still assuming the Ward analysis applies ...o_O
 
Thanks, I forgot about Ward Labs. But I wonder if it is really useful because the mineral content of the muni water does fluctuate. It says range detected of Ca is 11 - 26 mg/L and Hardness 52 - 118. So six months later I could be working with different numbers in reality, but still assuming the Ward analysis applies ...o_O

Seasonal fluctuations in brewing ions in tap water can be an issue. I know some folks who have had their water tested 2 (or more) times in a year to try to dial that in.

Another option is to build from distilled or RO water. I do that, not because of fluctuations, but because my water is both hard and alkaline, and not particularly suitable for many beer styles.
 
Thanks, I forgot about Ward Labs. But I wonder if it is really useful because the mineral content of the muni water does fluctuate. It says range detected of Ca is 11 - 26 mg/L and Hardness 52 - 118. So six months later I could be working with different numbers in reality, but still assuming the Ward analysis applies ...o_O
I would think that your filter would buffer the changes quite a bit.
 
Get a Ward Labs water report of your filtered water. Then, input that into the Brewer's Friend water tool, along with your grain bill. It will tell you exactly how much acid to add to your water. You'll be able to tweak minerals a bit as well.

I know there are other water calcs out there, but that's what works for me.

This is what I do, except that I use Beersmith's mash tab.
 
Unfortunately, Carbon filters don't remove hardness (Ca, Mg) or alkalinity.
Yeah, I knew about alkalinity, but I assumed it removed hardness. My water hardness is pretty low, both from my Ward Labs report and the municipal water report, so it's close enough that I don't have to worry about it. I guess an better solution on alkalinity would be to get a pH meter and acidify to measured alkalinity.
 
Yeah, I knew about alkalinity, but I assumed it removed hardness. My water hardness is pretty low, both from my Ward Labs report and the municipal water report, so it's close enough that I don't have to worry about it. I guess an better solution on alkalinity would be to get a pH meter and acidify to measured alkalinity.

Well, I've measured after adjusting acidity and it has always been close to the Beersmith prediction, so now I just go with the prediction.
 
Well, I've measured after adjusting acidity and it has always been close to the Beersmith prediction, so now I just go with the prediction.
After my last post, I did some research on pH testers. It looks like I'd be $100+ to get one that's any good. I asked myself, "Will my beer be $100+ better using measured pH rather than calculated?" And myself answered, "No, probably not."
 
After my last post, I did some research on pH testers. It looks like I'd be $100+ to get one that's any good. I asked myself, "Will my beer be $100+ better using measured pH rather than calculated?" And myself answered, "No, probably not."

I did splurge for the Milwaukee a few months ago. About $120 I think it was. It's very good, I haven't regretted it.
 
I did splurge for the Milwaukee a few months ago. About $120 I think it was. It's very good, I haven't regretted it.

I have an MW101 and an MW102. I don't think I'd trade them for anything close to the same price range.
 
Seasonal fluctuations in brewing ions in tap water can be an issue. I know some folks who have had their water tested 2 (or more) times in a year to try to dial that in.

Another option is to build from distilled or RO water. I do that, not because of fluctuations, but because my water is both hard and alkaline, and not particularly suitable for many beer styles.

I wonder if it's worth contacting my utility company to see if it's possible to obtain a report more often than once a year. Betcha they won't...
 
I have an MW101 and an MW102. I don't think I'd trade them for anything close to the same price range.

Yeah I have an M102. Nice machine. But now I'm rereading some of the stuff on Bru'nwater ... and they say this:

"Brewers should note that Automatic Temperature Compensating (ATC) pH meters only compensate for the response of the pH meter's electrode at varying temperature. That feature does not compensate for the actual pH shift produced chemically in the mash as mentioned above. All mash pH measurement should be performed at room-temperature."

Daggummit. Here I thought I was sittin' pretty with the ATC feature. But now this information indicates my mash sample needs to cool to room temp anyway! Which leads me to think that by the time that happens, most of the mash conversion is complete anyway and further pH adjustments are just pissing in the wind.

What's a brewer to do?
 
"Brewers should note that Automatic Temperature Compensating (ATC) pH meters only compensate for the response of the pH meter's electrode at varying temperature. That feature does not compensate for the actual pH shift produced chemically in the mash as mentioned above.

This is true.

But now this information indicates my mash sample needs to cool to room temp anyway! Which leads me to think that by the time that happens, most of the mash conversion is complete anyway and further pH adjustments are just pissing in the wind.

I think of mash pH readings as information to be used next time, e.g. if a certain recipe results in a measured pH that's off by "X" amount from the predicted pH, you can adjust the target by that difference (in the opposite direction) next time you build water for the same recipe. I don't chase incremental pH adjustments during a given mash.
 
This is true.



I think of mash pH readings as information to be used next time, e.g. if a certain recipe results in a measured pH that's off by "X" amount from the predicted pH, you can adjust the target by that difference (in the opposite direction) next time you build water for the same recipe. I don't chase incremental pH adjustments during a given mash.

Yes, I think Palmer says this. So I am ready to stop "chasing" and do more "predicting."
 
honestly i just set my milwaukee 101 to 60c, and test the mash at temp by sticking the probe in it, and add my acid drop wise....but i'm no pro brewer.....i shoot for 5.3 at temp, seems to give the best effec.
 
honestly i just set my milwaukee 101 to 60c, and test the mash at temp by sticking the probe in it, and add my acid drop wise....but i'm no pro brewer.....i shoot for 5.3 at temp, seems to give the best effec.

So, that Temperature Compensation knob you are setting to 60C is the manual equivalent of an ATC feature. Similarly, it compensates for the meter's electrode response at the higher temp, but not for the fact that the mash has a different pH at the higher temp. Your room temp pH would be somewhat higher than what you're measuring at 60C. FWIW.
 
I bought a Hanna Labs FC2142 Halo pH meter for beer and a RO system. The beer that I make has definitely increased in quality by using those and the Bru'n Water spreadsheet as I find it to be more accurate than the additions suggested by Beersmith. I just take a small sample of the mash and put it in the freezer part of the fridge for a few minutes to get it down to room temperature.
 
So, that Temperature Compensation knob you are setting to 60C is the manual equivalent of an ATC feature. Similarly, it compensates for the meter's electrode response at the higher temp, but not for the fact that the mash has a different pH at the higher temp. Your room temp pH would be somewhat higher than what you're measuring at 60C. FWIW.



i'm kinda aware of that...i've also read that the classic 5.2 mash ph target is AT mash temp, i think at room temp it would be 5.5? (don't recall)....but i just do it by feel, and i get the best efficiency with a ph of 5.3 at mash temp.....and my knob set to 60c....but it really only makes a couple percentage point difference to even adjust the ph at all....
 
After my last post, I did some research on pH testers. It looks like I'd be $100+ to get one that's any good. I asked myself, "Will my beer be $100+ better using measured pH rather than calculated?" And myself answered, "No, probably not."
You don't have to spend $100 to get a reliable pH meter. About half that and you're good. Check out the pH Dr.
 
AHA!!!! (American Homebrewers Association, and also AHA!!!!)

I just found this: EZ Water Calculator

It's a free Excel download. I just did a test calc with it and it looks good!

Whelp. I had some yeast ready so I decided to throw caution to the wind and brew a batch of Saison based on the calc in the little Excel sheet. It had me at 5.38, but I ended up at 5.9, measured after the end of the mash, with the sample having come to room temperature.

So I'm wondering....
1. Could the acidity of the mash have decreased over time? (It was a 90 minute mash)
2. Could the calculators in the little sheet be wrong?
3. Maybe the electrode in my pH meter needs to be replaced? (I recalibrated a few weeks ago)

I used 5 ml of lactic acid, one teaspoon, in this mash. I've used less than that in other non-dark brews and had mash pH of 5.6 or less.

Thoughts, O Wise Ones?
 
2. Could the calculators in the little sheet be wrong?

Some are better than others. I haven't looked at EZ Water in a long time, so can't comment one way or the other.
My personal recommendation is MpH. (Or BrewCipher, which contains MpH, if you also need a general purpose brewing workbook. Full disclosure: BrewCipher is mine.)

3. Maybe the electrode in my pH meter needs to be replaced? (I recalibrated a few weeks ago)

I recommend calibrating shortly before use.

I used 5 ml of lactic acid, one teaspoon, in this mash. I've used less than that in other non-dark brews and had mash pH of 5.6 or less.

It's better to measure acid additions with a pipette. A teaspoon is (nominally) less than 5 ml, but any given teaspoon could be higher/lower, and just isn't a very accurate measuring device, IMO.
 
Well, if this thread is wide open to advertisement (something that used to be taboo), then I recommend my 'Mash Made Easy' program, which is free and is a simple download at the link below.
 
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