Mash Water pH

[HopSong]

I don't yet know how this applies to me. I will be moving into BIAB and doing full boils for lower and medium gravity beers. Obviously(?), with BIAB, the volume of mashing water is very different than with conventional AG brewing.

I guess my question applies to both conventional and BIAB brewing.. and it is:

Is there a calculator of some sort that will help me determine just how much lactic acid or phosphoric acid I need to add to the batch once I know what the mash pH is?

I don't know volumes yet.. but, say for grins, I have put 8 G of water into my BK and bring it up to 160* and put my 12 lbs of grains in, stir, cover.. and check the pH in 15 minutes.. I find the pH is 5.8. Then arises the question.. is there a way to ball park the amount of LA or PH to add knowing the percentage of each to get the pH down to 5.2 for example.

Seems like I've seen people plug the numbers in and come up with "X" ml's

For my tired old brain, I can't seem to learn Martin's spreadsheet without some young person's help.. but there may be others that are "simpler"??

Thanks

 

[Spartan1979]

Try http://www.ezwatercalculator.com/

 

[Kaiser]

Is there a calculator of some sort that will help me determine just how much lactic acid or phosphoric acid I need to add to the batch once I know what the mash pH is?

You can try this one: http://www.brewersfriend.com/mash-chemistry-and-brewing-water-calculator/

I don't know volumes yet.. but, say for grins, I have put 8 G of water into my BK and bring it up to 160* and put my 12 lbs of grains in, stir, cover.. and check the pH in 15 minutes.. I find the pH is 5.8. Then arises the question.. is there a way to ball park the amount of LA or PH to add knowing the percentage of each to get the pH down to 5.2 for example.

Seems like I've seen people plug the numbers in and come up with "X" ml's

All the calculators that do mash pH prediction work on a trial and error basis. That is you adjust the acid additions until the mash pH prediction matches what you want. I know it’s more work but after a while you get a feel for how much to start with.

[quote
For my tired old brain, I can't seem to learn Martin's spreadsheet without some young person's help.. but there may be others that are "simpler"??

try the Brewer’s Friend calculator. It can do a lot more than just the basics but by default all those advanced sections are hidden. You only have to open the Grist section to enter details about your grist. And if you plan to add acids you need to open the Acids section. Since you are BIAB you don’t have to worry about sparge water. Just set total water to the same volume as the mash water and set sparge water to 0.

Kai

 

[ajdelange]

Yes, there is a simpler way and that's not to do any calculations at all. The basics are set forth in the Primer in the Stickies. The general idea is that you get the alkalinity out of the water by diluting it with RO to the point that the alkalinity is no longer significant or that you use 100% RO water. You then, based on the type of beer, use a specified amount of sauermalz (acidulated malt) usually 1 - 3% on the assumption that base malt will, with low ion water, come to a pH of about 5.7 and that you want to be about 0.3 lower than that. If you use darker malts you use less sauermalz up to light gravity stouts where you use no sauermalz. Heavier stouts: you are on your own. These may require that you add alkalinity.

This approach will usually get you a good beer. It's more or less the way people brewed in the days before they had computers and it's the way I brew now but I have done thousands of spreadsheet calculations and have the benefits of that experience.

A better approach is to take the grist you propose to use, put a pound of it in a pot with 3 pints of water, heat to strike temp and measure the pH with a good meter. Now add acid or base until the desired pH is reached. It takes a fine hand and you may overshoot. If you do start over until you get the hang of it. Keep track of the total acid required and scale that from 1 pound of grist to your full batch size. You are measuring the 'alkalinity of the mash.

 

[HopSong]

Thanks guys.. I'll re-look at BF and also try AJ's suggestion.

 

[WoodlandBrew]

What works for me is to mash in. Measure pH and add 88% lactic acid to achieve the pH I want.

This simple equation on this post is what works for me:
http://woodlandbrew.blogspot.com/2012/10/mash-ph.html

 

[mmonacel]

Quick question - my 10g MLT has a false bottom which has 1 gallon below the FB. When putting in total mash water for these calculators should I put in the full amount of water that's in the MLT or subtract 1g since it's not really in contact with the grains during the primary mash?

Edit: Actually after reading WoodlandBrew's link I see that the amount of water is pretty irrelvant. Using EZ Water Calc I can see that a gallon change in mash water for a given recipe only changes the pH by about .02.

 

[mmonacel]

What works for me is to mash in. Measure pH and add 88% lactic acid to achieve the pH I want.

For a process such as this I always wondered how effective it is since by the time you mix grain and water and let things settle for a few min to even out, you've already started the conversion process. By the time you've taken your wort sample, cooled it, and then tested it presumably about 15 min has already gone by (at least for me). At that point a great deal of conversion has already happened right? Is it already largely too late at that point to significantly effect the mash dynamics since from what I read (and my experience) almost all conversion is typically done in the first 20 min or so.

 

[WoodlandBrew]

Quick question - my 10g MLT has a false bottom which has 1 gallon below the FB. When putting in total mash water for these calculators should I put in the full amount of water that's in the MLT or subtract 1g since it's not really in contact with the grains during the primary mash?

It's the pH of the solution that is being calculated, which includes the water below the false bottom. So in theory, yes it should be included. However, in practice I don't think you'll see much difference.

 

[WoodlandBrew]

For a process such as this I always wondered how effective it is since by the time you mix grain and water and let things settle for a few min to even out, you've already started the conversion process. By the time you've taken your wort sample, cooled it, and then tested it presumably about 15 min has already gone by (at least for me). At that point a great deal of conversion has already happened right? Is it already largely too late at that point to significantly effect the mash dynamics since from what I read (and my experience) almost all conversion is typically done in the first 20 min or so.

That has not been my experience. If I am doing a protein rest then the adjustment occurs before the saccharification rest. There is more conversion earlier in the mash, but the five or ten minuets it takes to measure, adjust, and check is just a fraction of the 60 minute mash. Also, the pH adjustment is to aid in the conversion. Worst case is the first 10 minutes convert a little slow.

I would not consider it too late in the least.

 

[Inhiding]

I may be wrong but what I thought the intent of the OP was how much acid to add to X amount of wort/water/whatever at 5.8 pH to get down to 5.3 or wherever.

I have the same question. Is there a calculator or equation to tell one how much acid to add to lower pH a certain amount of points?

 

[ajdelange]

The reason for the test mash is so that you will be so close in the real mash that an adjustment won't be needed or will be a small one. Experience will also enable one to hit the target in the mash tun.

 

[Kaiser]

I may be wrong but what I thought the intent of the OP was how much acid to add to X amount of wort/water/whatever at 5.8 pH to get down to 5.3 or wherever.

I have the same question. Is there a calculator or equation to tell one how much acid to add to lower pH a certain amount of points?

The original question was about mash pH. The water pH reduction is generally only of interest for sparge water. most calculators can do that.

Kai

 

[HopSong]

Braukaiser has a nice chart that is pretty simple..

WoodlandBrew.. questions on yours. I'd guess it makes no diff if it's 88% Lactic or 88% Phosphoric..?? Also, you have up to 10# grist.. so, I guess that if you have 14# it 's the number for 10# + the number for 4# added together.. ?

A couple of good solutions to get me closer to the final mark..

Thanks again.

 

[WoodlandBrew]

Braukaiser has a nice chart that is pretty simple..

WoodlandBrew.. questions on yours. I'd guess it makes no diff if it's 88% Lactic or 88% Phosphoric..?? Also, you have up to 10# grist.. so, I guess that if you have 14# it 's the number for 10# + the number for 4# added together.. ?

A couple of good solutions to get me closer to the final mark..

Thanks again.

Phosphoric acid is actually much stronger than lactic. This is just for Lactic acid. About adding the two columns: yes, that will work fine. You probably want to start with half the recommended and see where that gets you.

 

[ajdelange]

Phosphoric acid is stronger than lactic (pK1 = 2.12 vs pK = 3.86) but both are 'strong' acids in this application because both those pKs are appreciably less than the target pH. To neutralize 100 ppm alkalinity would require 196 mg/L (2 mmol/L) phosphoric acid and 219 mg/L (2.4 mmol/L) lactic. Thus you need 20% more lactic, on a molar basis and that is because of the strength difference so perhaps it would be better to say phosphoric is strong and lactic almost strong. But you would need 2.46 mL of 88% phosphoric and 3.96 mL of lactic acid to neutralize the 100 ppm alkalinity in 5 gal. That's 61% more. This is because 88% lactic acid solution is appreciably less dense than 88% phosphoric.

And perhaps that is what was meant when 'strength' was mentioned but to a chemist (even amateur ones like me) 'strength' refers to pK.

 

[Demus]

Not a direct quote but Palmer says PH is more about being in the right ballpark, NOT on a specific base. In other words, 5.2 to 5.8 is the acceptable range, and if you're in it you should be fine. For BIAB and even batch sparging, acid additions can easily be avoided by predicting the mash PH based on water profile and grain bill like the above spreadsheets do. The main water parameters that effect PH are bicarbonate(total alkalinity), calcium and magnesium. Knowing these and your grain bill you should be able to save the time money and energy of measuring and adjusting PH. Unless of course you just enjoy being precise for precision's sake. If you fly sparge down to maximum efficiency, you may need acid additions as your spent grains lose buffering power toward the end of your sparge. This is one of the many reasons I batch sparge

 

[ajdelange]

It's true that there is no optimum pH but 5.2 - 5.8 is pretty wide. I think many of us have discovered the dramatic benefits of being in the 5.2 - 5.5 band. It usually takes some acid to get into this band. even with 0 alkalinity, and that is why German breweries use sauergut or sauermalz and British ones CRS.

 

[mabrungard]

Well, no single optimum. However, there are tighter ranges within the acceptable mash pH range that can help create certain flavor or perceptions in the finished beer. Biasing the pH to one end or the other will make substantially different beers.

You probably won't hear Palmer recommending such a wide range of acceptable mash pH in the future. There are advantages to tightening that up to the range that AJ mentioned.

 

[tonyolympia]

This is turning into a wide-ranging discussion, so I hope this question is appropriate...

My water is low in most ions but a bit high in bicarbonates (72 ppm). I'm using Bru'n Water to plan water treatments for a 100% pale malt beer I'm brewing soon (the Fuller's 1897 IPA, as featured in Mitch Steele's book of the same name). I was prepared to dilute with RO or use acid in the mash, but I saw that without doing either, I could bring my predicted mash pH down to 5.4 just by adding the gypsum and CaCl that I planned to add anyway.

Is this a commonly understood thing in water treatment, that you can use the flavor ions to drive mash pH? Because the pH prediction surprised me--I wasn't even shooting for obscene levels in my water. About 140 ppm calcium and 250 ppm sulfate.

If I understand this right, it seems like a tremendously convenient way to brew hoppy pale beers with my existing carbonate water, and not worry about acid or dilution with RO.

 

[Demus]

This is turning into a wide-ranging discussion, so I hope this question is appropriate...

My water is low in most ions but a bit high in bicarbonates (72 ppm). I'm using Bru'n Water to plan water treatments for a 100% pale malt beer I'm brewing soon (the Fuller's 1897 IPA, as featured in Mitch Steele's book of the same name). I was prepared to dilute with RO or use acid in the mash, but I saw that without doing either, I could bring my predicted mash pH down to 5.4 just by adding the gypsum and CaCl that I planned to add anyway.

Is this a commonly understood thing in water treatment, that you can use the flavor ions to drive mash pH? Because the pH prediction surprised me--I wasn't even shooting for obscene levels in my water. About 140 ppm calcium and 250 ppm sulfate.

If I understand this right, it seems like a tremendously convenient way to brew hoppy pale beers with my existing carbonate water, and not worry about acid or dilution with RO.

That is convenient, and probably all you need to worry about. These different water parameters drove different beer styles in different parts of the world. Here in the modern world, we need only modify our brewing water appropriately for the grain bill. If you want to brew a pale ale with soft, alkaline water, you may have issues without acid additions, but the salts you add for the proper flavor conveniently put you in the right target mash PH...

 

[ajdelange]

The principle that calcium (and to a lesser extent) magnesium react with malt phosphate to release mash pH lowering acid is indeed well known but it often (or even perhaps usually) cannot be relied upon to produce enough acid to lower pH into the desired range. In these cases acid must be obtained from elsewhere as from dark malt, sour malt, sauergut or acid from a bottle. If you are fortunate enough to be able to hit pH with the minerals you want to match your flavor profile you are a fortunate man indeed.

 

[helibrewer]

I use AJ's method: RO water, acidulated malt, then salts for the hardness and SO4:CL I'm looking for.

I have found it very easy to get a nice mash pH this way since you don't have to overcome any existing alkalinity. The acidulated malt has plenty of power in RO water.

 

[Spartan1979]

It's true that there is no optimum pH but 5.2 - 5.8 is pretty wide. I think many of us have discovered the dramatic benefits of being in the 5.2 - 5.5 band. It usually takes some acid to get into this band. even with 0 alkalinity, and that is why German breweries use sauergut or sauermalz and British ones CRS.

The 5.2- 5.5 is at room temperature, correct? What are the benefits to being in this band compared to 5.6-5.8?

 

[Kaiser]

The 5.2- 5.5 is at room temperature, correct? What are the benefits to being in this band compared to 5.6-5.8?

You'll get a lower mash pH and are less likely to extract excessive tannins during sparging.

This section has a nice summary of the benefits: http://braukaiser.com/wiki/index.php?title=How_pH_affects_brewing#enzymatic_activity

Kai

 

[ajdelange]

The 5.2- 5.5 is at room temperature, correct? What are the benefits to being in this band compared to 5.6-5.8?

Yes, room temperature.

As to the benefits: "All the flavors seem brighter." I put that in quotes because those aren't my words but I can't think of way to say it better.

 

[Demus]

Yes, room temperature.

As to the benefits: "All the flavors seem brighter." I put that in quotes because those aren't my words but I can't think of way to say it better.

I don't think this is correct. When would your mash be at room temperature? I'm no expert, but have read at least 6 home brewing books and plenty of articles as well brewed about 20 AG batches now. Everything I've read about mash PH is at mash temperature. The temperature itself influences the PH as well as the grain bill so measuring PH at any other time wouldn't be accurate...

 

[ajdelange]

When brewers started measuring pH they didn't slip a pen-sized device out of their shirt pockets and plunge it into wort or mash. They took a sample to the brewery's lab. By the time the sample got there it had cooled. Not to mention the fact that in those early days the reference electrode involved calomel which melts at mash and wort temperatures. As with other aspects of beer measurement standard practices evolved and were written down. The standards in the US are promulgated by the ASBC. Their "Methods of Analysis" call for wort to be measured at laboratory temperature. While calomel (mercuric chloride) is no longer used in electrodes they are still subjected to stresses from heating and cooling. It is better for them, in the sense that they will last longer, if they are not subjected to those stresses and so benefit from this practice but that's not the reason for it. The reason is that it provides a common reference. If one says 'at mash temperature' then one has to say what mash temperature that is. Beta glucan rest at 105 °F, protein rest at 125 °F, saccharification rest at 145 °F? Thus published pH results are for room temperature unless otherwise specified. It is true that this isn't the pH of the mash in the mashtun nor the wort in the kettle but you don't really care what those are. You are interested in finding out what number range that you can measure via the standard practice gives you good beer.

Now none of this means that standard practices can't be violated. Most texts don't specifically say what temperature they are referring to but given the practical considerations discussed above they are most probably talking lab temperature. Jean DeClerck specifically mentioned in his two volume text that all pH measurements are lab. Gordon Strong, in his book, says that he uses mash temperature pH.

 

[Demus]

It is true that this isn't the pH of the mash in the mashtun nor the wort in the kettle but you don't really care what those are. You are interested in finding out what number range that you can measure via the standard practice gives you good beer.

Now none of this means that standard practices can't be violated. Most texts don't specifically say what temperature they are referring to but given the practical considerations discussed above they are most probably talking lab temperature. Jean DeClerck specifically mentioned in his two volume text that all pH measurements are lab. Gordon Strong, in his book, says that he uses mash temperature pH.

I guess we'll have agree to disagree; the PH in the mash tun is the ONLY time it matters. Historical lab practices and probe materials don't change the fact that it's the mash PH, at whatever the mash temperature happens to be, that effects the outcome of the mash.
I also disagree with your assumption that texts are referring to lab temperature. We're talking about MASH PH, not LAB PH. everything I've read was pretty clear on this point...

 

[afr0byte]

I guess we'll have agree to disagree; the PH in the mash tun is the ONLY time it matters. Historical lab practices and probe materials don't change the fact that it's the mash PH, at whatever the mash temperature happens to be, that effects the outcome of the mash.
I also disagree with your assumption that texts are referring to lab temperature. We're talking about MASH PH, not LAB PH. everything I've read was pretty clear on this point...

So, kettle pH doesn't matter in terms of the hop profile? The finished pH of the beer doesn't matter in terms of shelf life? You also didn't seem to address his comments about what temperature is the mash pH supposed to be taken at?