Ideal pre and post boil PH

[kingmatt]

Hi all,

I know that a lot of emphasis is placed on dialing in an ideal PH range (usually 5.2-5.4) in the mash but I have been having a hard time finding consensus information on ideal pre-boil and post-boil PH ranges.

Some information I found indicates you want a lower pre-boil PH (around 5.2) to precipitate a better hot break and reduce extraction of harsh bitterness from your hops. I have also read that the lower PH tends to "mute" hop character in hoppy beers like pales and IPAs while making hop character in less hoppy beers (like lagers) more defined and crisper overall, which is a bit confusing to me.

In a beer like a double IPA (which I will be brewing this weekend) would it be better to shoot for a lower boil PH and increase my hop additions (if so, by how much?) to get the benefits of the better hop break and less harsh bitterness while still maintaining the high hop flavor/aroma character of the style? Or should I shoot for a boil PH of around 5.4 for the hoppier beers and lower it for less hoppy styles?

 

[Dgallo]

Hi all,

I know that a lot of emphasis is placed on dialing in an ideal PH range (usually 5.2-5.4) in the mash but I have been having a hard time finding consensus information on ideal pre-boil and post-boil PH ranges.

Some information I found indicates you want a lower pre-boil PH (around 5.2) to precipitate a better hot break and reduce extraction of harsh bitterness from your hops. I have also read that the lower PH tends to "mute" hop character in hoppy beers like pales and IPAs while making hop character in less hoppy beers (like lagers) more defined and crisper overall, which is a bit confusing to me.

In a beer like a double IPA (which I will be brewing this weekend) would it be better to shoot for a lower boil PH and increase my hop additions (if so, by how much?) to get the benefits of the better hop break and less harsh bitterness while still maintaining the high hop flavor/aroma character of the style? Or should I shoot for a boil PH of around 5.4 for the hoppier beers and lower it for less hoppy styles?

I’m sure the stricter brewers here will provide you with lots of info on this topic but if you’re in the 5.2-5.5 range you’ll be fine. As long as your there your water profile will have a bigger impact on the harshness of the bitterness from the hops. I like to be at Cl: 150ish and So4: 100ish and Ca: 80-100

 

[couchsending]

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).

 

[Robert65]

A few conflicting considerations. Actually a higher pH, toward 5.5, gives better break coagulation. But the lower end does produce a much smoother hop bitterness, though at the expense of efficient utilization (less but more pleasant bitterness.) And if you're using kettle finings like Irish moss or Whirlfloc, these are really only effective between pH 5.0 and 5.2. Below that wort fails to fine at all, above that it's much less effective. So a strategy many brewers use is to aim for a preboil pH of 5.4-5.5, and acidify to 5.0-5.2 before adding Whirlfloc. The lower pH of the chilled wort is also beneficial to fermentation for various reasons. But @Dgallo's advice is sound. 5.2-5.5 is a good compromise, and if you have his ~100ppm Ca, you can expect the wort pH to drop by up to 0.2 during the boil, helping you to maximize all these goals in the compromise.

 

[cabron99]

Subbed.

 

[enkamania]

And if you're using kettle finings like Irish moss or Whirlfloc, these are really only effective between pH 5.0 and 5.2.

I didn't know this. I've always thrown in the whirlfloc without a care in the world.

 

[kingmatt]

Sounds like I am going to have to trial and error it to see what I like best.

I will start using the Pliny brew log numbers couchsending posted (it is a double IPA after all!) and see what that gets me. I will then try to brew the same recipe with a higher pre-boil kettle PH of around 5.4 and adjust it down to 5.0-5.2 at the end of the boil and see if I notice a difference.

 

[Robert65]

Sounds like I am going to have to trial and error it to see what I like best.

Yep, can't beat real world evidence!

 

[Silver_Is_Money]

Charles W. Bamforth states that the typical Wort pH falls by ballpark 0.3 pH units during the boil (with some variability to this drop due to the specifics of the Wort). So ballpark 5.3 to 5.5 pH as measured at room temperature post mash, lautering, sparge, and run-off, or in other words immediately pre-boil, should place most typical Wort into the ballpark of 5.0 to 5.2 pH post boil and cooling.

 

[couchsending]

Charles W. Bamforth states that the typical Wort pH falls by ballpark 0.3 pH units during the boil (with some variability to this drop due to the specifics of the Wort). So ballpark 5.3 to 5.5 pH as measured at room temperature post mash, lautering, sparge, and run-off, or in other words immediately pre-boil, should place most typical Wort into the ballpark of 5.0 to 5.2 pH post boil and cooling.

I’ve never seen pH fall .3 during any of my 90 minute boils.

 

[Robert65]

I’ve never seen pH fall .3 during any of my 90 minute boils.

0.1-0.2 seems to be my experience. I suspect it's dependent on calcium concentration and a raft of other factors. I certainly wouldn't count on it to be a major component of achieving the desired reduction, but it happens to some degree.

 

[Silver_Is_Money]

I’ve never seen pH fall .3 during any of my 90 minute boils.

Quoting Bamforth:

The pH of wort drops about 0.3 units during boiling. Lower gravity worts have a higher pH before boiling, but a substantially bigger pH drop on boiling. Whereas the differences in pH of mashes over the range of gravities 7.5 - 20 degrees Plato is relatively constant, final wort pH’s are progressively lower as the gravity increases.

 

[enkamania]

Quoting Bamforth:

Explains why I don't see those big jumps, I don't make too many low gravity beers. Is there a simple lactic acid calculator out there? I might play with lowering the ph for the whirlfloc addition.

 

[couchsending]

Quoting Bamforth:

You can quote him all you want... still never seen it in maybe 200+ batches of beer. .1-.15 is what I’ve recorded, .2 is a rarity but I’ve seen it.

MW-102 calibrated every brew always measured at room temp.

The more hops you add even less of pH drop will occur cause the hops are increasing pH. I’ve found that leaf hops increase pH even more.

 

[couchsending]

0.1-0.2 seems to be my experience. I suspect it's dependent on calcium concentration and a raft of other factors. I certainly wouldn't count on it to be a major component of achieving the desired reduction, but it happens to some degree.

Yeah I need to look back at my notes on beers with different Ca amounts to see if there’s a substantial difference. I rarely go over 100ppm Ca in anything.

On another note does timing of kettle salt additions matter? If you are adding kettle salts so more Ca actually makes it into the fermenter is it beneficial to add at the beginning or end? Always wondered that.

 

[Silver_Is_Money]

Explains why I don't see those big jumps, I don't make too many low gravity beers. Is there a simple lactic acid calculator out there? I might play with lowering the ph for the whirlfloc addition.

I have a early (Alpha, though nice looking IMHO, and amazingly simple to use) Kettle pH calculator in the works that needs testing and may (worst case scenario) potentially have it all wrong. If you dare to test it, PM me. I don't intend to give Alpha level software out indiscriminately. Perhaps I will give out 4-5 copies, then shut the door. So please only ask if you validly intend to test it.

 

[Silver_Is_Money]

If we can presume from the testimony of those who have measured it that Bamforth is wrong in presuming a drop of 0.3 pH points across the boil, and the average drop in pH across the span of the boil is more on the order of 0.15 pH points, then to target 5.1 as the midrange ideal for post boil and cooling Wort pH, and actually hit within the target window of 5.0 to 5.2 pH post boil and cooling, one needs to make pre-boil acidification adjustments that will achieve a pre-boil pH of close to 5.25 as measured at room temperature.

Does this sound about right?

 

[couchsending]

Or you can just use acid to hit your target KO pH. For some beers you might want different pH targets at different times for different reasons.

Depending on how many hops you put in the kettle or the whirlpool you might not see a drop in pH at all.

 

[Silver_Is_Money]

If you adjust to pH 5.3 pre-boil (as measured at room temp.), then if the drop across the boil is only 0.1 points you will hit 5.2 pH, and if the drop is a full 0.3 points you will hit 5.0 pH post boil and cooling. So it appears that 5.3 should be a safe target pH to adjust toward pre-boil. Slightly up from my 5.25 pH target posted above.

 

[couchsending]

If 5.3 works for the beer you’re brewing? You might want it higher, you might want it lower. All depends on your boil temp, malt, desired bitterness, etc. etc.

 

[Silver_Is_Money]

If 5.3 works for the beer you’re brewing? You might want it higher, you might want it lower. All depends on your boil temp, malt, desired bitterness, etc. etc.

The sources I've come across seem to target 5.0 to 5.2 pH post boil and cooling. 5.2 if you want your hops to pop, and 5.0 if you want somewhat more muted hops, and 5.1 to split the difference. But adjustment must be made pre-boil in order for the hops to respond as intended. An industry renowned scholar says ~0.3 pH drop across the boil, and everyone who has responded to this thread says ~0.1 to ~0.2 pH drop. 5.3 as the pre-boil target (at room temp) seems to cover all bases.

 

[Robert65]

1) is the drop during the boil consistent, independent of pre-boil pH, natural or adjusted?

2) yes, you often want different values at different stages. 5.4-5.5 in the boil will be preferred for hop utilization and break formation, while 5.0-5.2 is required before dosing for carrageenan based kettle finings to function.

 

[couchsending]

The sources I've come across seem to target 5.0 to 5.2 pH post boil and cooling. 5.2 if you want your hops to pop, and 5.0 if you want somewhat more muted hops, and 5.1 to split the difference. But adjustment must be made pre-boil in order for the hops to respond as intended. An industry renowned scholar says ~0.3 pH drop across the boil, and everyone who has responded to this thread says ~0.1 to ~0.2 pH drop. 5.3 as the pre-boil target (at room temp) seems to cover all bases.

I’ve never seen or heard anything saying 5.2 will make the hops “pop” more versus 5.0. You might get better alpha utilization at 5.2 vs 5.0 but the brewers that I quoted or sourced info
From that all make world renowned hoppy beer all target as close to 5.0 as possible (or lower).

If you were to make a modern IPA and wanted a softer bitterness but wanted to use a decent amount of hops in the kettle/WP you might want start of the boil to be closer to 5.0 and end at 5.0. Might even require some acid if using large WP additions.

If you’re brewing say a lager with all Pils and really soft water you might want to start at 5.4 or 5.5 to get faster DMS conversion and a more assertive bitterness out of the hops and then adjust to 5.0 at the very end of the boil.

Then there’s darker beers which is a whole different discussion on kettle pH.

There’s no universal set value in my mind.

 

[Dgallo]

I feel like this has gotten a little ridiculous. Hit your intended mash ph. Adjust your post boil if needed

 

[Robert65]

I feel like this has gotten a little ridiculous. Hit your intended mash ph. Adjust your post boil if needed

My practice. Mash pH is priority. pH into the kettle is what it is. Adjust at the end if post boil will likely be above 5.2.

 

[couchsending]

I feel like this has gotten a little ridiculous. Hit your intended mash ph. Adjust your post boil if needed

So you’ve tested these variables? Or simply going on faith?

 

[Dgallo]

So you’ve tested these variables? Or simply going on faith?

I’m talking about the silly back and forth. If someone wants to go close to 5.0 so be it. If someone likes it closer to 5.4 ok. Ph isn’t the only thing that effects perceived bitterness and long story short, if the op preboil is 5.2-5.4 he will be fine. Ph between 2 tenths of a point will have far less of an impact of the final outcome of a beer than other components of the brewing process

 

[Silver_Is_Money]

I’ve never seen or heard anything saying 5.2 will make the hops “pop” more versus 5.0.

I got it from the book titled "Brew like a Monk". One of the Trappist Monasteries in Belgium changed from 5.2 to 5.0 pH post-boil (pre-fermentation) and their product drew complaints of suddenly having muted the hops. 'Orval' I believe.

 

[cire]

A good range of data available here. It would seem there are more factors at play than might be first thought.

 

[Silver_Is_Money]

A good range of data available here. It would seem there are more factors at play than might be first thought.

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.

 

[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).