Reconciling mash pH calculators

[rmr9]

I’ve been working through my process to sort out where a potential off flavor has been coming from and as part of that breakdown I used 2 different water calculators: Bru’n water and the advanced calculator from brewer’s friend.

Typically I go with Bru’n water which in the case of my water and grain bill suggests 0.7ml of 88% lactic acid to hit a mash pH of 5.4

Brewer’s friend suggests 3ml of lactic acid for the same grain bill and water.

When I enter 3ml lactic acid into Bru’n water it then gives me a mash pH of 5.1 so too low. I know this is an age old much debated topic but which is the better bet? I have an as yet unused pH meter so I have a feeling the answer is “use it fool” but I also can’t rule out having a random cell filled out in Bru’n water. Any thoughts?

I suppose I’ll throw this out there:
Grist - 98% barke pils, 2% Bestmalz chit

Ca: 53ppm
Mg: 6ppm
Na: 12ppm
SO4: 59ppm
Cl: 86ppm

 

[dmtaylor]

Use it, fool.

Anyway, you really should be mashing at a pH closer to 5.5 to 5.6, as measured at room temperature, not 5.4. So maybe when in doubt, use the lesser amount of acid. References on the mash pH topic:

https://www.homebrewtalk.com/threads/will-it-mash-at-ph-5-00.667992/page-2#post-8653242

https://www.homebrewtalk.com/thread...-at-5-2-to-5-6-ph.671764/page-12#post-8803629

https://www.homebrewtalk.com/thread...-brewers-do-not-mash-at-5-2-to-5-6-ph.671764/

That should keep interested people busy for a few days.

 

[rmr9]

Rabbit hole opened time to dive in! I’ll err on the side of caution and go with lower lactic acid amount and bust out the meter.

For a sanity check: I’ll dough in, wait about 10 minutes, take a wort sample and chill as quickly as possible in an ice bath and measure pH then adjust from there with lactic acid adding a little at a time until I get into the 5.5 target range if I’m not there already? Then once mash is complete, boil and measure pH at the end and potentially add more lactic to hit 5.2 into the fermenter?

 

[SonomaBrewer]

This is a can of worms that just keeps popping open.

To my mind, the “correct” mash pH needs to be per some target for “best” ie best pH for fermentability, best pH for sugar extraction, best pH for flavor, etc.

I have always used 5.4 (measured at room temp) based on Palmer’s talks and books, as this supposedly hits the middle between best for alpha and beta amylase activity.

But now I’m confused — why are you all saying is 5.6 “best” ? Is there really a tart flavor that comes with 5.4 (or perhaps is that from lactic addition beyond taste threshold?).

 

[MaxStout]

I've often heard a rule-of-thumb for mash pH ranges is 5.3-5.4 for light colored beers, 5.4-5.6 for dark beers. IIRC, that's also stated in Bru'nWater.

 

[rmr9]

I've often heard a rule-of-thumb for mash pH ranges is 5.3-5.4 for light colored beers, 5.4-5.6 for dark beers. IIRC, that's also stated in Bru'nWater.

I’ve seen similar pH ranges as well. Does it seem odd to anyone that the two calculators should differ so much? 0.7ml vs. 3ml seems a big difference.

 

[dmtaylor]

I’ve seen similar pH ranges as well. Does it seem odd to anyone that the two calculators should differ so much? 0.7ml vs. 3ml seems a big difference.

Are they both 88% lactic? One is not more dilute? Also, do the two calculators ask about mash volume vs. finished volume? Maybe there is something in the volume measurements.

I am thinking... 3 mL seems like too much, and 0.7 mL might be right. But I rarely use lactic so what do I know.

With the recipe you have posted, you will DEFINITELY need SOME acid, as the pH will be too high without any. So you are better off starting with the smaller amount and then add more ONLY IF more is needed later. And then after the boil, yes, that's a good idea too.

 

[rmr9]

Are they both 88% lactic? One is not more dilute? Also, do the two calculators ask about mash volume vs. finished volume? Maybe there is something in the volume measurements.

I am thinking... 3 mL seems like too much, and 0.7 mL might be right. But I rarely use lactic so what do I know.

With the recipe you have posted, you will DEFINITELY need SOME acid, as the pH will be too high without any. So you are better off starting with the smaller amount and then add more ONLY IF more is needed later. And then after the boil, yes, that's a good idea too.

Both 88% lactic both calculators ask for the same fields. I agree, 3ml sounds like a lot but that’s what it’s telling me I need. It is a very light grist but even still, water with zero alkalinity doesn’t seem like it should need a lot?

 

[MaxStout]

There's this thread with @ajdelange, about calculating lactic acid additions (and further posts covering phosphoric, too). The OP was asking re post-boil additions, so the target pH would be slightly different, but that still might give a good ballpark figure for mash.

 

[Brewer dad]

Speaking purely about the discrepancies in amount of acid called for, are you sure the acid editions being called for are the same portion of the process in the two applications? By that I mean, is this the amount of acid you’re just putting in your mash, Sarge, or both?

For example in the beer I brewed last night I added 6ml 88% lactic to the mash, and 1.3ml to the sparge. I use Brewfather and have only just started looking at brunwater recently, though off the top of my head I remember sparge acidification being first in brunwater. Maybe you’re looking at mash addition on one and sparge on the other?

 

[rmr9]

Speaking purely about the discrepancies in amount of acid called for, are you sure the acid editions being called for are the same portion of the process in the two applications? By that I mean, is this the amount of acid you’re just putting in your mash, Sarge, or both?

For example in the beer I brewed last night I added 6ml 88% lactic to the mash, and 1.3ml to the sparge. I use Brewfather and have only just started looking at brunwater recently, though off the top of my head I remember sparge acidification being first in brunwater. Maybe you’re looking at mash addition on one and sparge on the other?

Hmm good point. I know in brewer’s friend I selected to add only to mash, maybe I need to have a look at Bru’n water and make sure I don’t have something erroneously filled out or that I’m looking in the wrong place.

There's this thread with @ajdelange, about calculating lactic acid additions (and further posts covering phosphoric, too). The OP was asking re post-boil additions, so the target pH would be slightly different, but that still might give a good ballpark figure for mash.

Thanks for the pointer to the thread! I’ll bust out some scratch paper and see if I can use the formula to calculate and see where it lands.

 

[Bramling Cross]

I think "use it fool" is the correct answer because which calculator is correct is a bit of a canard. For all you know, neither may be correct (for various reasons). But you won't know that unless you use the meter. What you really want to know is whether you're hitting your target mash pH. Fortunately you already have a pH meter, so, as you said, "use it fool!"

Once you start using the meter you should quickly be able to determine which calculator is closer to what is actually going on in your tun and then make any necessary adjustments. Just make certain that you have a decent pH meter and you're calibrating it properly and using it correctly. There's nothing worse than a bad pH meter poorly used. It'll send you off on all kinds of dumb directions.

 

[rmr9]

I think "use it fool" is the correct answer because which calculator is correct is a bit of a canard. For all you know, neither may be correct (for various reasons). But you won't know that unless you use the meter. What you really want to know is whether you're hitting your target mash pH. Fortunately you already have a pH meter, so, as you said, "use it fool!"

Once you start using the meter you should quickly be able to determine which calculator is closer to what is actually going on in your tun and then make any necessary adjustments. Just make certain that you have a decent pH meter and you're calibrating it properly and using it correctly. There's nothing worse than a bad pH meter poorly used. It'll send you off on all kinds of dumb directions.

I think I have a decent meter. Came with some calibration solution packets so I’ll be calibrating it before each use. I figure let the mash go 10-15 minutes, pull a sample and cool it in an ice bath to room temp measure and make adjustments if needed.

Quick question for the meter users out there: how do you store your calibration solutions? My thinking was to store them in clean empty water bottles but not sure if that’s the best bet. In my lab days the solutions came in their own bottles which made it easier - that or we’d use falcon tubes but I don’t have any of those on hand!

 

[Bramling Cross]

I'm not fond of buying bottles of calibration solutions. They tend to be expensive and they go off well before I can hope to use even a quarter of the bottle. As such, I have a strong preference for using these. I'll dump a sachet into the calibration vessels that came with my meter, then switch out the solution monthly without having to worry about the big bottle losing its accuracy. They seem to strike a good balance between cost-effectiveness and accuracy.

Also, rather than using a water bath, try tossing three old coffee mugs in your freezer on the night before brew day. Run your samples (or scoop up your samples) in those frozen coffee mugs, then toss them back in the freezer. Set a timer for 6-8 minutes and you should have quickly cooled samples. If you over shoot the chilling you can pulse them in the microwave. That's the easiest and quickest way that I know how to do it.