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BIAB - Full Volume and pH

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brew-bandit

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How do you control mash pH on a full volume BIAB mash?

Looking at a BrunWater it seems the pH will go up a good amount if you do full volume.
 
Acidulated malt is my weapon of choice. Usually 1-2% of total grain bill will do it.

That or 88% lactic acid. Or, you can use phosphoric acid (which has less flavor, but requires more to achieve the same pH.)

Brew on :mug:
 
I use cacl2 and gypsum in all of my brews. Lighter grain bills are supplemented with 88% lactic acid.
 
Buuuuuuump....

For any of the methods described, do you use a standard amount and not worry about checking pH? Or do you use a calculator to get your pH as close as you can, then not worry about it? OR, do you use a calculator to get your calculator to get close, check pH during mash and adjust as needed with more of whatever your method of choice may be?

My first BIAB was the Centennial Blonde, and the thread warns that it is a thin mash and can have pH issues at full boil. Sure enough, the OG sample tasted pretty astringent. I'll see how it tastes when finished, but let's just say I want to control this better from now on!

Ike
 
@skydiver30960

I use acid malt but have also used lactic acid.

Mash acidification requirements are calculated with Bru'n water

Mash Acidification Alt.png

The actual mash pH is measured with a Hach Pro+ 30 minutes into the mash

Mash pH.jpg

Measured and planned pH are compared, any adjustments to the needed amounts of acid malt are made to subsequent mashes. On the fly adjustments are not done. (It would be too late as the mash is 30 minutes in)

The meter is calibrated on brew day and the pH measured on a cooled sample (room temperature ~75F)

DSC02412.jpg
 
What about our friend, John Palmer's post about PH and full volume mashing in BYO? According to him...

"At the end of the continuous sparging process, the mash pH typically rises to around 6 as the sugars are extracted and the buffering effect of the malt and wort is replaced by water. This rise in mash pH tends to extract greater proportions of tannins, polyphenols and silicates into the wort that have a dulling effect on the taste. Batch sparging (in which first, second and even third runnings are combined to produce the wort) can exacerbate this effect because all of the wort is drained away, including the majority of the buffering capability, before adding the next sparge volume. No-sparge brewing provides for a stable lautering pH that is not significantly different than the mash pH, due to the large buffering capacity of the malt.

The amount of water used for continuous sparging (3 to 5 gallons) is typically 1.5 times as much for the mash. When you brew with the no-sparge method, this 3 to 5 gallons is added to the mash tun at the end of the mash, before recirculation, and allows the mash tun to be simply drained to achieve full boil volume. By using more grain and adding all the water during the mash, you can relax and not worry about mash pH, astringency and undershooting your gravity."

http://byo.com/malt/item/1375-skip-the-sparge
 
What about our friend, John Palmer's post about PH and full volume mashing in BYO? According to him...

"At the end of the continuous sparging process, the mash pH typically rises to around 6 as the sugars are extracted and the buffering effect of the malt and wort is replaced by water. This rise in mash pH tends to extract greater proportions of tannins, polyphenols and silicates into the wort that have a dulling effect on the taste. Batch sparging (in which first, second and even third runnings are combined to produce the wort) can exacerbate this effect because all of the wort is drained away, including the majority of the buffering capability, before adding the next sparge volume. No-sparge brewing provides for a stable lautering pH that is not significantly different than the mash pH, due to the large buffering capacity of the malt.

The amount of water used for continuous sparging (3 to 5 gallons) is typically 1.5 times as much for the mash. When you brew with the no-sparge method, this 3 to 5 gallons is added to the mash tun at the end of the mash, before recirculation, and allows the mash tun to be simply drained to achieve full boil volume. By using more grain and adding all the water during the mash, you can relax and not worry about mash pH, astringency and undershooting your gravity."

http://byo.com/malt/item/1375-skip-the-sparge

On the red bits.

The lautering pH and mash pH are going to be identical with full volume mashing. By definition there is no possible way they could differ. Lautering with BIAB is pulling the bag and draining/squeezing.

Using more grain will increase the planned OG. If the added grain increases the percentage of roast/crystal malts, the pH will be reduced. Adding more base malt will thicken the mash somewhat so would have some effect for sure. Not much though in comparison to adding roast/crystal or acid malt.

Then you're back to the OG issue. Changing the planned beer to meet mash pH requirements. I prefer changing the mash pH to meet the requirements of the planned beer. Makes more sense to me.
 
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Measured and planned pH are compared, any adjustments to the needed amounts of acid malt are made to subsequent mashes. On the fly adjustments are not done. (It would be too late as the mash is 30 minutes in).

Why?

I remember seeing a thread where ajdelange talks about making on-the-fly pH adjustments to his mash (I can go try to dig it up, I saw it awhile ago). Besides, can't you just add time to your mash if need be? Mashing too long shouldn't have any ill effects as long as your temperature is maintained.
 
On the red bits.

The lautering pH and mash pH are going to be identical with full volume mashing. By definition there is no possible way they could differ. Lautering with BIAB is pulling the bag and draining/squeezing.

Using more grain will increase the planned OG. If the added grain was increasing the percentage of roast/crystal malts, the pH will not be buffered to any significant extent. Adding more base malt will thicken the mash somewhat so would have some effect for sure. Not much though.

Then you're back to the OG issue. Changing the planned beer to meet mash pH requirements. I prefer changing the mash pH to meet the requirements of the planned beer. Makes more sense to me.

Good points to consider.

However, this article was written long before I got into the brew game, so this is just a guess, but do you think the 20% grain bill boost was advice given before BIABers started reporting efficiencies in the 70's, and into the 80's?

:off:Gavin, do us all a favor and post your alt recipe in the database will ya? It looks delish!:off:
 
Why?

I remember seeing a thread where ajdelange talks about making on-the-fly pH adjustments to his mash (I can go try to dig it up, I saw it awhile ago). Besides, can't you just add time to your mash if need be? Mashing too long shouldn't have any ill effects as long as your temperature is maintained.

Most if not all of the reactions of importance are complete at this stage.

I'm just following the info from the brew science forum. Perhaps someone more skilled than I could make intra-mash pH adjustments but to me it does not seem feasible as the mash pH is not constant from the start to the end of the mash.

Measuring too early and making adjustments based on that figure is impractical as final (planned) mash pH has not been reached.

A test mash is often advocated by @AJDelange . An exact scale minimash. Same grist percentages and grain:water ratio. This allows refining the mash before brew day.

I miss typed in my post earlier. I have made correction.
 
Good points to consider.

However, this article was written long before I got into the brew game, so this is just a guess, but do you think the 20% grain bill boost was advice given before BIABers started reporting efficiencies in the 70's, and into the 80's?

:off:Gavin, do us all a favor and post your alt recipe in the database will ya? It looks delish!:off:

The increase in base malt is often given as a solution to the perceived (not actual) limitations of BIAB regarding its efficiency. It's not off base advice if you are using a crush more in line with a 3 vessel setup so is often decent advice. Not needed if you are taking simple measures to take advantage of an un-blockable manifold (bag) and crushing finer.

A finer crush and squeezing the bag/draining the bag massively increases conversion speed and coupled with the thinner mash increases conversion efficiency. The squeezing and/or draining gives a very high lautering efficiency.

Result: Consistent and predictable mash efficiencies 85%+

:off:Thanks for the kind words on the Alt. It is my first recipe and I do intend to post it. I was hoping to get some impartial feedback in an upcoming competition before doing so but I guess I don't need to wait. I'm really delighted with it. :off:
 
Most if not all of the reactions of importance are complete at this stage.

I'm just following the info from the brew science forum. Perhaps someone more skilled than I could make intra-mash pH adjustments but to me it does not seem feasible as the mash pH is not constant from the start to the end of the mash.

Measuring too early and making adjustments based on that figure is impractical as final (planned) mash pH has not been reached.

A test mash is often advocated by @AJDelange. An exact scale minimash. Same grist percentages and grain:water ratio. This allows refining the mash before brew day.

I miss typed in my post earlier. I have made correction.

They way I'm visualizing it, if your pH isn't low enough at the 30 minute stage, the starches aren't in solution to be converted by the amalayse. So by lowering the pH at the 30 minute mark, you're essentially just giving the amalayse something more to work on by dissolving more starches into solution.

I could be way off base though.

In either case I should be able to report some experimental results since I messed up my last mash and forgot to add the acid malt until 45 minutes in. So I added the acid malt and an additional 30 minutes to the mash. Hopefully I didn't majorly screw it up, it tasted good at pitching time and smells great.

Always amazing how forgiving beer can be!
 
They way I'm visualizing it, if your pH isn't low enough at the 30 minute stage, the starches aren't in solution to be converted by the amalayse. So by lowering the pH at the 30 minute mark, you're essentially just giving the amalayse something more to work on by dissolving more starches into solution.

I could be way off base though.

In either case I should be able to report some experimental results since I messed up my last mash and forgot to add the acid malt until 45 minutes in. So I added the acid malt and an additional 30 minutes to the mash. Hopefully I didn't majorly screw it up, it tasted good at pitching time and smells great.

Always amazing how forgiving beer can be!

30 minutes in, my single infusion mashes are all but done. The acidulated malt is just part of the regular grain bill and milled/mixed with everything else. All mashes need some form of acid. Acid in the form of lactic acid is easy to add, acid malt, crystal malts, roast malts can all provide this. Thinner mashes will dilute the acid so more is need to reach the desired pH range.

All that being said, even if you do nothing to monitor/adjust pH it will have negligible effect on the efficiency. Other factors such as milling, mash thickness, temperature and lautering efficacy play a much greater role.

pH is primarily related to the optimization of all the other things. You need all the pieces in place before worrying about the minimal effects pH will play.

largely unrelated to efficiency, tannin extraction and astringency are the real and present risks with lighter grain-bills and thinner mashes. Us BIAB'ers need to be more aware of this in the same way fly-spargers need to consider runoff pH.

even if the pH is ~5.8 to 6.0 you'll still get conversion and decent efficiency. Flavor is however likely to be adversely affected.

Again, I am far from experienced and am open to correction but I think you need to dispel the notion of a fixed mash pH. It is dynamic as the various reactions occur. That is why too early a reading of mash pH is not advised, nor intra-mash adjustments. It can lead to errors.

It's easy to test this idea. Check your mash pH at the start, middle and end of the mash on samples at room temperature.
 
How should you test ths pH with strips? At mash temp or room temperature?

The strips are unreliable. I've not used them but am again parroting the words of the water gurus here on HBT. There is a good piece on them in Bru'n water's water education section. They can be off by 0.2-0.3 and rely on color changes which are rendered useless by colored wort in many cases.

All pH readings are generally taken and reported at room temperature.

See post #11 for more details. It might answer things better.
 
For what it's worth I use 88% lactic acid for lowering the pH of my RO brewing water and add in salts and minerals to match the style of beer I'm planning to brew. I do this the night before brewing and use a pH meter to confirm the results after the water's been sitting overnight.

The next time I check the pH is when I'm pouring a glass of beer, but I don't always do that, check the finished beer's pH. I wouldn't trust anything but a recently calibrated pH meter for taking any of the readings though.
 
30 minutes in, my single infusion mashes are all but done. The acidulated malt is just part of the regular grain bill and milled/mixed with everything else. All mashes need some form of acid. Acid in the form of lactic acid is easy to add, acid malt, crystal malts, roast malts can all provide this. Thinner mashes will dilute the acid so more is need to reach the desired pH range.

All that being said, even if you do nothing to monitor/adjust pH it will have negligible effect on the efficiency. Other factors such as milling, mash thickness, temperature and lautering efficacy play a much greater role.

pH is primarily related to the optimization of all the other things. You need all the pieces in place before worrying about the minimal effects pH will play.

largely unrelated to efficiency, tannin extraction and astringency are the real and present risks with lighter grain-bills and thinner mashes. Us BIAB'ers need to be more aware of this in the same way fly-spargers need to consider runoff pH.

even if the pH is ~5.8 to 6.0 you'll still get conversion and decent efficiency. Flavor is however likely to be adversely affected.

Again, I am far from experienced and am open to correction but I think you need to dispel the notion of a fixed mash pH. It is dynamic as the various reactions occur. That is why too early a reading of mash pH is not advised, nor intra-mash adjustments. It can lead to errors.

It's easy to test this idea. Check your mash pH at the start, middle and end of the mash on samples at room temperature.

Thanks for the info, it sounds like I've been thinking about it all wrong. I had it lodged in my brain that mash pH needed to be between 5.2 and 5.3 after reading all the water chemistry threads (or at least a hundred odd pages of it).

So when you BIAB what are your pH benchmarks that you shoot for?

Mid-mash, post boil, and completed beer?
 
Thanks for the info, it sounds like I've been thinking about it all wrong. I had it lodged in my brain that mash pH needed to be between 5.2 and 5.3 after reading all the water chemistry threads (or at least a hundred odd pages of it).

So when you BIAB what are your pH benchmarks that you shoot for?

Mid-mash, post boil, and completed beer?

It doesn't matter what you are using for a manifold, it's the mash thickness or lack therof that is the issue with full volume mashing. The target mash pH should be the same regardless of your sparging /no sparging (ie using a thicker mash).

As far as I know, there is no difference there. Again a brewer with more knowhow hopefully will correct me if I'm blowing smoke. Sparge water acidification is a separate issue that I have no experience with.

I generally shoot for 5.4+/- 0.1 as this is a good happy medium for alot of styles. I just got the upgraded Bru'n Water and it gives more detailed recomendations depending on the style.

My target pH can be tweaked a bit as I wouldn't want to overpower a recipe with too much acidulated malt. the most I have used so far has been ~6%. This figure will seem very high if you speak to brewers not doing full folume mashing. Usually 1-2% is more applicable with thicker mashes.

While not suggesting it as routine, the braukaiser has shown that even in higher amounts (up to ~13%) acid malt is impossible or extremely difficult to detect. Other brewers report favorable flavors imparted by an appropraite use of acid malt. It may also play a role in head retention.

I only measure mash pH at about 30 minutes in as I don't plan on any corrective measures. If my adjustments did not result in the desired pH I note it and tweak the amount in the future. With this approach I am getting very close between measured and planned pH values.

A better approach from an accuracy standpoint would be a test mash. Something I will try for sure at some point.

I don't measure strike water pH as it is not useful to know. Mash pH is minimally affected by the water pH.

Nor do I measure kettle or beer pH. These could give the brewer some usable data. I'm just not sure what I would do with it, so I don't measure it. Perhaps as I learn more these numbers may become more important to me.

The mash pH target is not set in stone. If someone were brewing the same beer over and over they could really nail down a pH which gave a taste they preferred and have that as their goal. Taste is the key objective.
 
Acidulated malt is my weapon of choice. Usually 1-2% of total grain bill will do it.

Sorry to necro a thread, but I wondered what your methodology is for deciding how much to add. I have no interest in running a chemistry lab, so looking for way to estimate. You're quite active in BIAB threads so would love to have a bit of guidance if you have the time to offer it.

Cheers!
 
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