Ideal pre and post boil PH

[Silver_Is_Money]

We also learn that the final beer pH is essentially identical for all of the above cases 1 through 4.

But here's the scary part:

... in at least two cases the beers produced from the acidified mashes were considered to have poor flavours being described as 'empty' and astringent, ...

It seems potentially safer to not acidify much up front in the mash if this is the potential consequence.

 

[Robert65]

That's a great resource. In Table XI we learn that:

1) For an unacidified mash at 5.73 pH the drop during the boil is 0.25 points, to 5.48 post boil and cooling
2) For a mash acidified to 5.59 pH the drop during the boil is 0.18 points, to 5.41 post boil and cooling
3) For a mash acidified to 5.40 pH the drop during the boil is 0.10 points, to 5.30 post boil and cooling
4) For a mash acidified to 5.20 pH the drop during the boil is 0.01 points, to 5.19 post boil and cooling

The more one acidifies the mash up front, the less the fall in pH witnessed during the boil, until at some juncture of early acidification there is no drop in pH during the boil.

So there is confirmation of the suspicion implied in my question (1) above (#22.) Those figures are not identical to but on the general order of my experience with mashes in the range of 5.4-5.6, and of course we must remember that that data is from one series of trials with many variables we will not match in any real situation. But it does show the difficulty in predicting acid requirements for this purpose.

 

[couchsending]

We also learn that the final beer pH is essentially identical for all of the above cases 1 through 4.

But here's the scary part:

It seems potentially safer to not acidify much up front in the mash if this is the potential consequence.

This goes against everything I’ve ever read. Higher pH in the mash will more likely lead to astringency.

 

[Silver_Is_Money]

The safest overall bets may be to target 5.6 pH for the mash and 5.2 pH post boil and cooling (albeit with the adjustment aiming at 5.2 pH being made pre-boil, such as to benefit the hops).

????????????

 

[Silver_Is_Money]

This goes against everything I’ve ever read. Higher pH in the mash will more likely lead to astringency.

Would that be during the mash, or during run-off (a stage of lautering)? Or is one leading to the other?

 

[enkamania]

The safest overall bets may be to target 5.6 pH for the mash and 5.2 pH post boil and cooling.

????????????

This is what I’m trying this weekend.

 

[couchsending]

The safest overall bets may be to target 5.6 pH for the mash and 5.2 pH post boil and cooling.

????????????

I would say definitely not unless you’re going to adjust before the boil.

The difference in hoppy beers especially between 5.6 and 5.2 at the start of the boil is dramatic. The bitterness of very different.

 

[kingmatt]

But here's the scary part:

It seems potentially safer to not acidify much up front in the mash if this is the potential consequence.

So would that be strictly defined as adding acid (lactic, phosphoric, citric etc) to the mash, or ANY attempt to adjust mash ph (salt additions, cutting with distilled, acid malt etc)?

 

[couchsending]

Would that be during the mash, or during run-off (a stage of lautering)? Or is one leading to the other?

One is leading to the other.

 

[Silver_Is_Money]

So would that be strictly defined as adding acid (lactic, phosphoric, citric etc) to the mash, or ANY attempt to adjust mash ph (salt additions, cutting with distilled, acid malt etc)?

The article referenced (linked) in post #29 above states specifically "two cases of the acidified mashes". Acid malt would be a means to acidify the mash. I doubt that mineralization was being considered here, though clearly I can not enter the mind(s) of the one(s) who penned the content found within the linked dissertation, and in addition the article only came to me today when its link was provided in post #29, so my thoughts as to its potential ramifications and consequences are and must be seen at this juncture as mere speculation on my part. All of this (I.E., what is gleaned and/or surmised from the dissertation) must remain in the realm of speculation until independently verified or falsified via experimentation (actual practice).

 

[kingmatt]

I brewed a double IPA today shooting for the Pliny numbers posted above (5.45 mash, 5.24 pre-boil, 5.07 knockout). I adjusted my mash pH to 5.44 and my pre-boil pH to 5.25 with 85% phosphoric acid. I checked my pH at 10 minutes left in the boil and was surprised to see that it had dropped to 5.02, even with 8oz of hops.

I hit my SG dead on and had a great, compact cold break. I will post back with how the beer turns out.

 

[couchsending]

I brewed a double IPA today shooting for the Pliny numbers posted above (5.45 mash, 5.24 pre-boil, 5.07 knockout). I adjusted my mash pH to 5.44 and my pre-boil pH to 5.25 with 85% phosphoric acid. I checked my pH at 10 minutes left in the boil and was surprised to see that it had dropped to 5.02, even with 8oz of hops.

I hit my SG dead on and had a great, compact cold break. I will post back with how the beer turns out.

What was your Ca target for this beer?

Anyone know if the acid variety would cause a bigger drop in pH during the boil? Phosphoric vs. Lactic?

Not sure if this was covered in the study someone just linked but from what I’ve read recently the more Ca in the mash the more phosphates are precipitated and hence less buffer so you will get a larger pH drop during fermentation. So presumably less buffer during the boil as well? Bigger pH drop there?

 

[kingmatt]

What was your Ca target for this beer?

Anyone know if the acid variety would cause a bigger drop in pH during the boil? Phosphoric vs. Lactic?

Not sure if this was covered in the study someone just linked but from what I’ve read recently the more Ca in the mash the more phosphates are precipitated and hence less buffer so you will get a larger pH drop during fermentation. So presumably less buffer during the boil as well? Bigger pH drop there?

My target Ca was relatively high at 97 ppm.

 

[couchsending]

My target Ca was relatively high at 97 ppm.

Just adding to mash and sparge or did you add Ca salts to the kettle?

 

[kingmatt]

Mash and sparge

Just adding to mash and sparge or did you add Ca salts to the kettle?

 

[Silver_Is_Money]

That's a great resource. In Table XI we learn that:

1) For an unacidified mash at 5.73 pH the drop during the boil is 0.25 points, to 5.48 post boil and cooling
2) For a mash acidified to 5.59 pH the drop during the boil is 0.18 points, to 5.41 post boil and cooling
3) For a mash acidified to 5.40 pH the drop during the boil is 0.10 points, to 5.30 post boil and cooling
4) For a mash acidified to 5.20 pH the drop during the boil is 0.01 points, to 5.19 post boil and cooling

The more one acidifies the mash up front, the less the fall in pH witnessed during the boil, until at some juncture of early acidification there is no drop in pH during the boil.

If (as it appears) 5.2 pH is an ideal target for allowing the hops to shine, and at the juncture of 5.2 pH there is anticipated to be no further drop in pH across the span of the boil, then the process might be sitting right in front of us:

1) For the case of a mash that is anticipated to be in a state wherein mash pH will be no higher than 5.8 (or perhaps even pH 5.9) and no lower than 5.2 as measured at room temperature), do nothing to adjust the mash pH. The vast majority of beers will be found to reside within this category.
2) If the mash is anticipated to measure at above 5.8 (or perhaps even pH 5.9) or below 5.2 pH (as measured at room temperature) adjust in advance to hit (a room temperature measured) 5.5 to 5.6 pH during the mash.
3) Cool a pre-boil (fully post all stages of lautering/sparging) sample and take its pH at 20 degrees C.
4) Adjust (if necessary) to bring the Wort to pH 5.2 at this stage. Then proceed to the boil step.
5) That's it, there is no step 5, as the Wort should remain at ~5.2 pH throughout the boil, and the hops should be happy.

Thoughts on this are welcome.

 

[bierhaus15]

Sort of a mini rant and oversimplification, but IMMO, it is worth noting that much of the data on "ideal mash pH" comes from sources that were working on very different issues than what the average home brewer or IPA brewer is trying to solve for today. When Kunze and Narziss were working on this, the name of the game was making extremely clear, haze stable, and light colored pils of low gravity worts and optimizing mashes that had a very high pH due to using very pale and low-kilned, lager malts. Moreover they were largely concerned with the optimization of malt extraction-lauter efficiency, fermentability, viscosity, and achieving very low beer color. All while held to the restrictive standards of the RGB and without the use of most mash/kettle additives.

Per hopping, "smooth bitterness" is still the ideal within German brewing. When Kunze says to acidify the boil within the last 30 minutes of the boil, it is because they want to reduce isomerization - not to make the hop character shine - and ensure proper DMS removal... and ensure FAN and TSN levels provide high fermentability/pH drop using lager yeasts. That is not to say these are bad practices at all, but the reasons for doing so were not to make the best Pliny the Elder clone.

A very simple summary of German process could be to target mash pH of 5.5-5.6 (for attenution, protein break, wort viscosity, lauter effeciency and low color) with some form of lactic acid in the mash and then acidify in kettle to 5.0-5.2 for the aforementioned reasons. Final beer pH should be around 4.4-4.5.

In contrast, US/UK systems for pH control are different. Pale malts provide a higher pH drop in the mash due to kilning and the use of high Ca promotes a lower mash pH and ensures lauter pH stays constant. Compared to German process where you can see a swing in lauter pH, requiring reduction, 100-200 ppm mash Ca is normal and ensures the pH does not spike and the boil is at a relatively constant pH; 5.2-5.4. Bitterness is not a huge issue either, given the varieties used, and cultural tolerances for bitterness and hop character. Kettle pH reductions can be up to 0.3 pH, as Bamforth states, and is not uncommon. Final beer pH is lower, 4.0-4.4. Add in 5-10+% caramel/specialty malts and people often say, "what bitterness."

 

[dmtaylor]

This goes against everything I’ve ever read. Higher pH in the mash will more likely lead to astringency.

What if... everything you've ever read is wrong?!:

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

 

[brewbama]

What if... everything you've ever read is wrong?!:

There’s a whole lotta truth there.

The same ideas useful for one condition gets repeated often enough until it become the best practice for every condition.

Given your system, processes, recipe, water, equipment profile, mash schedule, etc, etc you could produce results contrary to what someone else experienced using a completely different set of variables.

Measure for yourself.

 

[couchsending]

What if... everything you've ever read is wrong?!:

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

It’s not.

 

[hopjuice_71]

Kettle pH reductions can be up to 0.3 pH, as Bamforth states, and is not uncommon. Final beer pH is lower, 5.0-5.4. Add in 5-10+% caramel/specialty malts and people often say, "what bitterness."

Just for clarification, did you mean 4.0-4.4?

 

[bierhaus15]

Just for clarification, did you mean 4.0-4.4?

Oops, yes.

 

[Clyde McCoy]

I don’t think you’ll find consensus on this anywhere. I’d suggest brewing the same beer twice, one with pre boil pH starting around 5.4 and one starting at say 5.0 and see what the difference is.

I’ve done a lot of digging on this topic and found plenty of info and opinions for sure but never performed the test myself.

On beers with Pilsner malt I always aim for a higher boil pH. I boil at low temps due to elevation so DMS is a bigger issue for me than if I was at sea level. The half life of the DMS precursor is twice as long at 200* compared to 212. A low boil pH lengthens that time even more. 5.4-5.5 Is what I shoot for. Plus I think with such soft water profiles the higher pH helps with a sharper bitterness especially when using lower alpha hops like say Saaz for all additions. Just make sure to lower close to 5.2/5.0 for the last 10 of the boil.

If not using Pilsner malt and in hoppy beers I’ll shoot for closer to 5.2 or potentially even lower at the start (depending on the style). Also make sure you adjust at the end. Especially with hoppy beers the hops increase pH or prevent the natural pH drop that occurs during boiling if you’re adding a lot of hops to the kettle.

There’s a line in Phil Markowski’s book on Saisons where Yvan De Baets chastised Orval for lowering their pH in the boil from 5.4 to 5.0. He said it changed the beer and reduced the bitterness too much. He likes his bitter beers.

There’s a photo of a brew log you can find online for Pliny. Start of the boil pH is 5.24, end is 5.07. Mash pH is 5.45. Acid additions are used after mash and at end of the boil.

Heard Chad Yakobsen talk about making sure KO pH is 4.9-5.1 for all beers.

Heard Henry from Monkish talk about making sure KO pH is close to 5.0 for highly hopped beers.

Most lager brewing texts talk about KO pH needs to be 5.2-5.0.

Yeast supposedly will reach a certain pH regardless of its starting value (I have not tested this either) but the premise behind adding acid to lower the pH of the wort is so the yeast can get to that lower pH faster so you have a quicker start to fermentation and an overall healthier ferment. Don’t quote me on that, someone smarter should probably chime in on this (or all of it).

Following up on this,

My understanding is that you want a mash pH of 5.2–5.4 to maximize the activity of the amylases responsible for saccharification and liquification. John Kimmich suggests a pH of 5.1-5.3 at mash temperature, which isn't far off 5.2-5.4 measured at 68F.

In terms of pre-boil pH, again a pH of 5.2-5.4 seems desirable, as much lower than that, and you'll reduce hop utilization, but much higher and the hop utilization increases, but the bitterness is harsher.

Based on the brewers you're quoting, it seems that an end of boil pH of 5.0-5.2 promotes fermentation.

Somewhat related,

Here's a photo of the pH meter at Hill Farmstead where it reads pH 5.16 https://brewbokeh.com/images/place-hillfarmstead19.jpg

And here at 1:34, you can see Shaun Hill tasting what I presume is the sweet wort (?) (near mash temperature?); the meter reads pH 5.19

 

[dmtaylor]

And here at 1:34, you can see Shaun Hill tasting what I presume is the sweet wort (?) (near mash temperature?); the meter reads pH 5.19

Presume anything you want. Everybody else does.

 

[Clyde McCoy]

Presume anything you want. Everybody else does.

No need for the saucy attitude, chief. Presume was followed by not one, but two question marks.

Finished beer is far lower pH. Hopped wort tastes terrible. What do you think he's tasting?

 

[dmtaylor]

Finished beer is far lower pH. Hopped wort tastes terrible. What do you think he's tasting?

I'm not really sure. It seems likely that it is raw wort since the pH isn't mid 4's, but that's only a guess. More importantly, we have no idea what temperature it is.

And if you think that's saucy, you ain't seen nothing. In real life I'm a fairly huggable guy. Hugs to you.

 

[Dgallo]

I'm not really sure. It seems likely that it is raw wort since the pH isn't mid 4's, but that's only a guess. More importantly, we have no idea what temperature it is.

And if you think that's saucy, you ain't seen nothing. In real life I'm a fairly huggable guy. Hugs to you.

You seem like a good hugger to me... just saying

 

[couchsending]

In terms of pre-boil pH, again a pH of 5.2-5.4 seems desirable, as much lower than that, and you'll reduce hop utilization, but much higher and the hop utilization increases, but the bitterness is harsher.

A boil pH around 5.4 makes sense if you’re trying to maximize IBUs from a certain amount of hops... however if we’re talking modern hoppy beer that is dry hopped (often at excessive levels) then there are so many other variables at play when it comes to bitterness or the perception of bitterness.

I don’t think you can draw anything from those videos or photos. There is an old Pro Brewer post where Shaun says that pre and post boil pH are the most important... however who knows if he still feels that way or not. He did say they dumped an insane amount of beer when they expanded and that he had to relearn everything he thought he knew about brewing....

If you’re adjusting at different times throughout the process I personally think that room temp mash pH anywhere from 5.3 to 5.5 is fine. Lower might be better but again that depends on so many other variables like grain bill, water chemistry, process, equipment, etc etc etc.

 

[Silver_Is_Money]

The real key is to adjust whereby to have post boil and cooling (and thereby room temperature measured) Wort pH sitting at around 5.1 to 5.2 heading into fermentation. Some even say 5.0 pH here. That makes the range of acceptability 5.0 to 5.2 pH.

 

[Clyde McCoy]

I'm not really sure. It seems likely that it is raw wort since the pH isn't mid 4's, but that's only a guess. More importantly, we have no idea what temperature it is.

The pH meter he's using is an OAKTON Economy pH 11 (confusing name). The bottom number indicates the temperature.

As far as I can tell,

Photo: pH 5.16, temp 19.8C
Video: pH 5.19, temp 27.9C

We don't know what he's tasting, so these numbers are of limited value, but perhaps these give some insight into the process of someone who is very secretive about techniques. I do find it curious that the two values are so similar.