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General Category => All Grain Brewing => Topic started by: bassriverbrewer on February 15, 2011, 09:33:16 PM

Title: Acidifying the mash
Post by: bassriverbrewer on February 15, 2011, 09:33:16 PM
Has anyone ever tried using acids other than lactic to acidify a mash such as citric,malic or tartaric acid? Just curious
Title: Re: Acidifying the mash
Post by: mabrungard on February 15, 2011, 10:08:36 PM
That is an interesting thought.  These are somewhat more flavorful acids and you can typically find them in a homebrew shop that deals with wino's.  Other than their flavor contributions, I can't see a reason not to consider using them.  In some cases, these acids might have a flavor component that you might want in your beer. 

I look forward to hearing from those who have used these acids in beer usage.
Title: Re: Acidifying the mash
Post by: lonnie mac on February 15, 2011, 10:15:37 PM
Funny, I have never used lactic. I have most always used citric. It takes sooooo little to drop the ph that I can't see it imparting a flavor component to any beer. Years ago, I used phosphoric and that worked very well too but the citric was more readily available.
Title: Re: Acidifying the mash
Post by: bassriverbrewer on February 15, 2011, 11:55:43 PM
how much do you use and how much of a drop in ph do you get?
Title: Re: Acidifying the mash
Post by: lonnie mac on February 16, 2011, 12:55:59 AM
how much do you use and how much of a drop in ph do you get?


I can't say how much as I don't measure. I acidify 20 gallons of my total brew day water at once in one container and monitor the PH actively. I add just literally a pinch at a time and watch the PH fall until I get it to where I want it. Usually right around 6.0.
Title: Re: Acidifying the mash
Post by: alikocho on February 21, 2011, 10:27:17 PM
I'm pretty certain that Charlie Papazian mentions using citric acid at some point in the Complete Joy of Homebrewing. I don;t have a copy to hand to check, but I seem to remember it....
Title: Re: Acidifying the mash
Post by: nateo on February 22, 2011, 04:50:53 AM
Here's a link to some questions about using lactic acid, and the byproducts from doing so:
http://www.homebrewtalk.com/f128/alkalinity-lactic-acid-222141/

Take careful note of what AJ Delange says.
Title: Re: Acidifying the mash
Post by: frteach on February 22, 2011, 11:29:15 PM
I generally do a lot of sour mashing since I learned how.  Upstate NY has pretty good water for hitting target ph, but I still do it anyways.   I always do a sour mash with any recipe requiring wheat. I think it can really mellow the tartness of wheat and still not be sour-sour.  Manhattan judges never detected any lactic acid traits in my beer.  I don't want it do be too sour but it does take a little off the edge of the tart wheat flavor.  From several books, sour mashing was popular for acidifying a mash. 

If it helps, what I do, depending on the grain bill and style, I like to do a 5% minimash 1-3 days before the main mash depending on if I want sour or just acid.  Mash the 5% as usual then rest to 90 degrees, pitch about 2oz of unmashed grain on top, put lid back on overnight.  One person in my club said he did it in a kettle and put 4 brewbelts on it.  My acidity tests show 1lb after 1 day usually makes 5.0. (store spring water here is 5.5) Next day prepare the full grain bill and add the acid mash to the grains and water, then mash the whole thing.  There isn't enough contact time for a new fermentation on the big mash and boiling is going to take care of the critters.

My lambics & sours I do 20% for 2-3 days and still pitch WY3278 or High grav and IMHO, sour mashing is a very good way of acidifying a mash and is more controllable than some think. 
Title: Re: Acidifying the mash
Post by: Kaiser on February 23, 2011, 03:21:09 AM
I can't say how much as I don't measure. I acidify 20 gallons of my total brew day water at once in one container and monitor the PH actively. I add just literally a pinch at a time and watch the PH fall until I get it to where I want it. Usually right around 6.0.

What you are doing is to partially neutralize the alkalinity of the water. Depending on your water that may not take much acid at all. It's different when you are adding malt and the acid is used to drop the mash pH significantly.

Kai
Title: Re: Acidifying the mash
Post by: gmac on March 14, 2011, 09:28:43 PM
I can't say how much as I don't measure. I acidify 20 gallons of my total brew day water at once in one container and monitor the PH actively. I add just literally a pinch at a time and watch the PH fall until I get it to where I want it. Usually right around 6.0.

What you are doing is to partially neutralize the alkalinity of the water. Depending on your water that may not take much acid at all. It's different when you are adding malt and the acid is used to drop the mash pH significantly.

Kai

I couldn't find lactic or phosphoric acid around here so I got citric from a wine shop.  Is it better to lower the water pH prior to mashing as noted above or should I add it to the mash (will certainly take me some trial and error to get that right)? 
Title: Re: Acidifying the mash
Post by: denny on March 14, 2011, 09:35:29 PM
I couldn't find lactic or phosphoric acid around here so I got citric from a wine shop.  Is it better to lower the water pH prior to mashing as noted above or should I add it to the mash (will certainly take me some trial and error to get that right)? 

Mash pH is what matters, not water pH.  Mash in, read the pH, and adjust as necessary.
Title: Re: Acidifying the mash
Post by: mabrungard on March 14, 2011, 09:52:10 PM
Yes, water pH is less the issue for mash use.  It is water alkalinity that is the primary concern which drives mash pH.  Fortunately, Bru'n Water is a tool that enables brewers to adjust their water alkalinity prior to doughing in to improve the probability that they will hit their desired mash pH.  

I personally adjust alkalinity of my mash water with acid prior to doughing in, but it should be roughly equivalent to adding the acid after doughing in and the volume of acid added should be equal.  Your choice.  I do recommend that even when calculating what the acid amount is with Bru'n Water, you should reserve a bit of the acid and check the mash pH after a few minutes and see if you still need to add the remainder.  

The acidification calculator used in Bru'n Water is directly from the work by AJ Delange and I've used it for years.  It is quite accurate as long as you know your water alkalinity and acid type and strength.
Title: Re: Acidifying the mash
Post by: gordonstrong on March 28, 2011, 12:24:09 AM
Late reply, but I use phosphoric acid exclusively.  You can buy it online from mail order homebrew shops if you can't get it locally.  Several places carry it.
Title: Re: Acidifying the mash
Post by: denny on March 28, 2011, 03:56:25 PM
Late reply, but I use phosphoric acid exclusively.  You can buy it online from mail order homebrew shops if you can't get it locally.  Several places carry it.

Gordon, what differences have you found between phosporic and lactic acids that made you choose phosporic?
Title: Re: Acidifying the mash
Post by: gordonstrong on March 28, 2011, 04:05:21 PM
Never used lactic, so I can't compare.  I just know that it's an off flavor in beer, so I try to avoid using it in case it has any flavor carry-over.  I figured that phosphoric acid has more common elements with beer ingredients (malt, specifically) than lactic (which is a milk souring acid), so I tried to keep it in the family.  Not saying other ways are wrong, just what I do.
Title: Re: Acidifying the mash
Post by: denny on March 28, 2011, 04:06:29 PM
Thanks, that's what I was wondering.
Title: Re: Acidifying the mash
Post by: Tristan on April 03, 2011, 07:20:26 PM
Anyone use hydrochloric?  I haven't heard of a lot of people using it and I'm curious as to why. 

I've been using lactic acid in very small quantities (maximum of 3-4ml in 6 gallon batches) and I don't taste a flavor carry over.  I've read that phos precipitates calcium and my water is low to begin with (23ppm) so I'm a bit reluctant in buying it.
Title: Re: Acidifying the mash
Post by: johnf on April 03, 2011, 11:32:05 PM
Anyone use hydrochloric?  I haven't heard of a lot of people using it and I'm curious as to why. 

I've been using lactic acid in very small quantities (maximum of 3-4ml in 6 gallon batches) and I don't taste a flavor carry over.  I've read that phos precipitates calcium and my water is low to begin with (23ppm) so I'm a bit reluctant in buying it.

British breweries use a product called CRS which is hydrochloric and sulfuric blended.

I think the primary reason homebrewers aren't using it is that it is a strong acid and risky to handle.

Title: Re: Acidifying the mash
Post by: mabrungard on April 04, 2011, 01:34:29 AM
Hydrochloric acid is fine for acidification.  It is typically available in pretty high strength, so you might have to be very careful with measurement and handling. 

I see that you've been listening to Palmer regarding phosphoric acid and calcium precipitation.  AJ DeLange debunked that myth a few months ago.  The mash is teeming with phosphates and the minor addition of phosphoric acid does little to change the potential for calcium precipitation.  It does not happen.  Using phosphoric acid is fine for mash acidification.  Phosphoric acid has very little taste effects on the beer.
Title: Re: Acidifying the mash
Post by: hopfenundmalz on April 04, 2011, 01:50:22 AM
I have been using Phosphoric acid to adjust the pH downward.  Glad to read I was not having problems.  I was worried there for a second.

The beer has been turning out pretty good.
Title: Re: Acidifying the mash
Post by: gordonstrong on April 04, 2011, 02:43:13 AM
I honestly don't know where some of these goofy ideas come from.  People are going along fine, then someone says something on the internet, and all of a sudden everyone is dumping olive oil in their beer.  If your processes are working for you, stop looking for evidence to change to something else.  In this case, it should be pretty evident whether you accidentally dropped all the calcium out of your wort.  If you don't have the signs of it, then chances are it didn't happen.  Theoretical is one thing, but if you have actual empirical evidence to the contrary, just believe your own senses. 
Title: Re: Acidifying the mash
Post by: Tristan on April 04, 2011, 03:06:57 AM
I see that you've been listening to Palmer regarding phosphoric acid and calcium precipitation.  AJ DeLange debunked that myth a few months ago. 

Good to know!

I honestly don't know where some of these goofy ideas come from.  People are going along fine, then someone says something on the internet, and all of a sudden everyone is dumping olive oil in their beer.  If your processes are working for you, stop looking for evidence to change to something else.  In this case, it should be pretty evident whether you accidentally dropped all the calcium out of your wort.  If you don't have the signs of it, then chances are it didn't happen.  Theoretical is one thing, but if you have actual empirical evidence to the contrary, just believe your own senses. 

I agree, with the exception of when a piece of information comes from a credible source such as John Palmer (where the phos reference comes from).  If someone sees a wild theory online there is good reason to doubt it, but when it comes from a credible source there is less of a reason for dispute.   

Good point on continuing a process that works.  I don't have the most refined palate so it may just be that the lactic is adding  a flavor I can't detect.  If I can find a more neutral acid (like phos) to use I'd really like to try it.  Most of the local breweries are using phosphoric.

Everyone's process and understanding keeps evolving as more information becomes available.  I figure if I can find a better method for acidifying the mash then why not consider alternatives?  Gordon, I'm sure that's one of the reasons you're publishing a book; which by the way, I can't wait to get my hands on!
Title: Re: Acidifying the mash
Post by: malzig on April 04, 2011, 10:52:32 AM
I honestly don't know where some of these goofy ideas come from.
Probably from this infamous reaction:
2 H3PO4 + 3 Ca(OH)2 –> 6 H(OH) + Ca3(PO4)2
Title: Re: Acidifying the mash
Post by: mabrungard on April 04, 2011, 02:08:05 PM
To be clear, I am not saying that the calcium phosphate precipitation reaction does not take place. 

The gist of my message above is that adding phosphoric acid does not appreciably change the amount of phosphate ion in the mash.  This is due to the malt contributing on the order of 1% phosphate to the mash (this is about 10,000 ppm) and an acid addition only being maybe a 100 ppm.  So the added phosphate doesn't really change things appreciably.  Therefore, the additional potential to precipitate out more calcium is pretty small.
Title: Re: Acidifying the mash
Post by: gordonstrong on April 04, 2011, 03:01:35 PM
To be clear, I am not saying that the calcium phosphate precipitation reaction does not take place. 

Right; neither am I.  But what's that got to do with what's actually taking place in the mash?  The "goofy idea" is that you can take a perfectly reasonable concept and then totally misapply it in practice.  Just because a basic fact is true doesn't mean that subsequent statements are also true, particularly if they ignore physical evidence to the contrary.  This isn't a new problem; it's been around long enough that there is a Latin term for it: non sequitur.  It's also how people wind up with beers that taste like Alka Seltzer.
Title: Re: Acidifying the mash
Post by: denny on April 04, 2011, 03:36:10 PM
I honestly don't know where some of these goofy ideas come from.  People are going along fine, then someone says something on the internet, and all of a sudden everyone is dumping olive oil in their beer.  If your processes are working for you, stop looking for evidence to change to something else.  In this case, it should be pretty evident whether you accidentally dropped all the calcium out of your wort.  If you don't have the signs of it, then chances are it didn't happen.  Theoretical is one thing, but if you have actual empirical evidence to the contrary, just believe your own senses. 

Gordon, I love you....no, not like THAT!  ;)
Title: Re: Acidifying the mash
Post by: denny on April 04, 2011, 03:39:22 PM

I agree, with the exception of when a piece of information comes from a credible source such as John Palmer (where the phos reference comes from).  If someone sees a wild theory online there is good reason to doubt it, but when it comes from a credible source there is less of a reason for dispute. 

Even when something comes from a "credible source" you do yourself a disservice to blindly accept it without trusting your own observations and experience.  Although the source may have established credibility in the past om some things, there's no absolute guarantee that source is accurate on all things all the time.  You need to use your own experience and common sense to see how that advice relates to you.
Title: Re: Acidifying the mash
Post by: tschmidlin on April 04, 2011, 04:07:22 PM

I agree, with the exception of when a piece of information comes from a credible source such as John Palmer (where the phos reference comes from).  If someone sees a wild theory online there is good reason to doubt it, but when it comes from a credible source there is less of a reason for dispute.

Even when something comes from a "credible source" you do yourself a disservice to blindly accept it without trusting your own observations and experience.  Although the source may have established credibility in the past om some things, there's no absolute guarantee that source is accurate on all things all the time.  You need to use your own experience and common sense to see how that advice relates to you.
Or to put it another way, just because a reaction happens in a test tube doesn't mean it happens (or matters) under relevant conditions.  It's a big problem in medical research, one that too many people forget.  Ultimately your in vitro results have to be tested in situ.
Title: Re: Acidifying the mash
Post by: ccarlson on April 04, 2011, 04:14:10 PM
I agree. It's like my experience with Fermcap. Many experts on here recommended it, I bought a BIG bottle of it and it's a total waste of money, in my opinion. However, I have no one to blame by myself for buying the large size.
Title: Re: Acidifying the mash
Post by: tschmidlin on April 04, 2011, 04:25:25 PM
I agree. It's like my experience with Fermcap. Many experts on here recommended it, I bought a BIG bottle of it and it's a total waste of money, in my opinion. However, I have no one to blame by myself for buying the large size.
Give it another try, it works for many of us in practice.  Feel free to ask for usage recommendations if you think that will help.  If it still doesn't work for you . . . where do you live?  If you're close I'll buy it off of you, I love the stuff. :)  I use it in the boil and during fermentation.
Title: Re: Acidifying the mash
Post by: ccarlson on April 04, 2011, 04:36:00 PM
Thanks, but I already threw it away. I tried it several times and with different amounts, some at almost double the recommended ones. It would help a little but not enough that I felt was worth having something more than the 4 basic ingredients in my beer.
Title: Re: Acidifying the mash
Post by: tschmidlin on April 04, 2011, 04:37:25 PM
Bummer.   Sorry it didn't work for you.
Title: Re: Acidifying the mash
Post by: Tristan on April 04, 2011, 06:55:09 PM
Tom, Gordon, Martin and Denny, thanks for the well stated points and advice!  Sometimes I have a tendency to focus on the wrong things in brewing and over look the things that matter most.  When I run out of lactic acid I'll give phosphoric a shot!
Title: Re: Acidifying the mash
Post by: malzig on April 05, 2011, 03:55:11 AM
To be clear, I am not saying that the calcium phosphate precipitation reaction does not take place. 
Right; neither am I.  But what's that got to do with what's actually taking place in the mash?  The "goofy idea" is that you can take a perfectly reasonable concept and then totally misapply it in practice.  Just because a basic fact is true doesn't mean that subsequent statements are also true, particularly if they ignore physical evidence to the contrary.  This isn't a new problem; it's been around long enough that there is a Latin term for it: non sequitur.  It's also how people wind up with beers that taste like Alka Seltzer.
Calcium is typically limited in tap water around here and I see plenty of beers that exhibit the physical evidence that they probably would have benefited from a little more Calcium.  I couldn't, in good conscience, recommend that brewers here add more phosphate, instead of Calcium Chloride or Sulfate.

I'd be curious to see the evidence that Phosphoric Acid doesn't remove calcium from the mash, though.
Title: Re: Acidifying the mash
Post by: tschmidlin on April 05, 2011, 04:33:57 AM
I couldn't, in good conscience, recommend that brewers here add more phosphate, instead of Calcium Chloride or Sulfate.
I'm sorry, maybe I'm misunderstanding . . . why is it either/or?  Why can't it be both?  If you had water that was low in calcium but high in bicarbonate, couldn't you add CaCl to bump up the Ca while adding phosphoric acid to acidify the mash in a pale beer?  Although if your water lacks calcium then maybe it is low in lots of things and doesn't actually need acidification anyway.

As far as phosphoric acid not removing calcium from the mash, I think the point is that there is already a lot of phosphate in the mash from the malt, so adding a little more isn't going to impact the precipitation much.  So it's not "does it or doesn't it", but "does it matter"?  I never acidify my mash and always add calcium, so I don't really know, but Martin and Gordon's points make sense from a chemistry standpoint.
Title: Re: Acidifying the mash
Post by: gordonstrong on April 05, 2011, 10:56:28 AM
If you throw a rock in the ocean, does it raise the water level?  Then my God, we're all going to be flooded!

See the analogy?

Phosphoric acid removing calcium doesn't mean that you don't have calcium for brewing.  The evidence is that the resulting beer doesn't show any signs of a calcium deficiency.
Title: Re: Acidifying the mash
Post by: malzig on April 05, 2011, 11:23:01 AM
I would rarely need to add acid after adding an appropriate amount of calcium, so it would mostly be an either-or situation.  Also, our local water has about 4 ppm calcium.  Maybe that's why adding something that would remove additional calcium seems like a goofy idea, to me.  But it also means I don't have any personal experience with the effects of adding phosphoric acid, either.

I worry that this argument sounds an awful lot like the "malt converts completely in xx minutes" argument.  Well, your mash may convert that fast, but his doesn't.  You may find that removing additional calcium by adding phosphoric acid doesn't hurt your beer, but that might not be true for the guy with 4, 10 or maybe even 50 ppm calcium in his water.

Really, I have no problem with adjusting the pH with phosphoric acid.  Just the statement that it doesn't precipitate calcium without any evidence to support that claim.

The stoichiometry is relatively simple, so we can figure out how much calcium could be lost, which might be helpful.  How much phosphoric acid are you typically adding?
Title: Re: Acidifying the mash
Post by: gordonstrong on April 05, 2011, 11:54:48 AM
Maybe 1/4 to 1/2 a tsp in 5 gallons of RO water.
Title: Re: Acidifying the mash
Post by: johnf on April 05, 2011, 12:24:28 PM
I would rarely need to add acid after adding an appropriate amount of calcium,

That sounds odd to me. I usually brew with RO water adjusted to 50 ppm Ca with CaCl or more. I have to add acid to most mashes to get a pH around 5.4 (measured by a freshly calibrated pH meter).

I don't think anyone is saying adding marginal phosphoric acid precipitates no marginal calcium but rather that it is immaterial. When you have breweries like Sierra Nevada produces hundreds of thousands of barrels of technically great beer made with phosphoric acid that displays no symptoms of low calcium, the burden of proof for the claim that phosphoric acid should not be used lies with the claimant.
Title: Re: Acidifying the mash
Post by: Tristan on April 05, 2011, 01:00:02 PM
I can see where both sides are coming from and can see the validity of a "fart in the wind" argument.  Maybe that's where the sulfur comes from on all my beers with WLP830?  It's gonna take lagering for that aroma to dissipate.  Now that you've all told me to challenge everything, I don't believe any of you!   ;D

Maybe 1/4 to 1/2 a tsp in 5 gallons of RO water.

What concentration?  I can find 10% Phos at my local shop, but not 75% that most of the brew pubs would use.  I wonder if this is another safety consideration for the home brewer?  
Title: Re: Acidifying the mash
Post by: mabrungard on April 05, 2011, 01:54:23 PM
I would rarely need to add acid after adding an appropriate amount of calcium, so it would mostly be an either-or situation.  Also, our local water has about 4 ppm calcium.  Maybe that's why adding something that would remove additional calcium seems like a goofy idea, to me.  But it also means I don't have any personal experience with the effects of adding phosphoric acid, either.

The calcium precipitation reaction is dependent upon the concentration of calcium in the water.  And the reaction takes a percentage out, not a fixed amount.  So that nice 4 ppm Ca water would not be losing much and it clearly needs supplemental Ca to support good fermentation and clarification.  The bottom line is that this water needs calcium to bring it into a suitable range for brewing and any minor loss due to phosphate precipitation can be ignored. 

By the way, one of my clubmates found that DudaDiesel sells food grade 75% phosphoric acid for about $14/ qt.  In these small quantities, it does not incur the hazardous goods shipping surcharge. 
Title: Re: Acidifying the mash
Post by: Tristan on April 05, 2011, 03:07:02 PM
By the way, one of my clubmates found that DudaDiesel sells food grade 75% phosphoric acid for about $14/ qt.  In these small quantities, it does not incur the hazardous goods shipping surcharge. 

Thanks for the information Martin.  I saw this come up on a Google search last night and thought about pulling the trigger.  It's good to know someone else in the brewing community has experience with this vendor.
Title: Re: Acidifying the mash
Post by: johnf on April 05, 2011, 03:29:55 PM
My LHBS sells 75%. I don't think it is dangerous to handle per se (certainly safer than strong acids, but don't give it to your 5 year old to play with). I think it is more the hazardous material shipping restrictions Martin sites which tend to drive up the cost a bit (same reason it is hard to get Acid #5 or similar, though that is genuinely more dangerous than 75% phosphoric).

Another advantage to the 10% stuff is that you will be adding more of it and so maybe you are measuring with teaspoons and tablespoons rather than pipettes. I think a lot of people would prefer working with larger quantities.

I'm an acid malt fanboy myself though I might experiment with other methods of acidification.
Title: Re: Acidifying the mash
Post by: gordonstrong on April 05, 2011, 09:03:45 PM
Maybe 1/4 to 1/2 a tsp in 5 gallons of RO water.

What concentration?  I can find 10% Phos at my local shop, but not 75% that most of the brew pubs would use.  I wonder if this is another safety consideration for the home brewer?  

I generally use this: http://www.northernbrewer.com/brewing/review/product/list/id/451/category/61/
Title: Re: Acidifying the mash
Post by: mabrungard on April 05, 2011, 09:33:24 PM
Maybe 1/4 to 1/2 a tsp in 5 gallons of RO water.

You don't have to add acid willy nilly.  Bru'n Water includes AJ DeLange's very capable water acidification calculator.  If you know your water profile, the acid type and strength, you can calculate what your addition is fairly precisely.  I've been using that calculator for a decade and its correct every time.
Title: Re: Acidifying the mash
Post by: gordonstrong on April 05, 2011, 09:39:40 PM
Maybe 1/4 to 1/2 a tsp in 5 gallons of RO water.

You don't have to add acid willy nilly.  Bru'n Water includes AJ DeLange's very capable water acidification calculator.  If you know your water profile, the acid type and strength, you can calculate what your addition is fairly precisely.  I've been using that calculator for a decade and its correct every time.

It's not willy nilly.  It's until I hit a certain pH target.  It's just that the amount of acid varies since RO water doesn't always have the same mineral profile.  The problem is that I don't know my water profile every time.  It changes.  So rather than analyzing my water every time I use it, I measure the pH, which is what I really care most about anyway.
Title: Re: Acidifying the mash
Post by: narvin on April 08, 2011, 05:04:04 AM
So, using phosphoric acid results in an insignificant amount of phosphate compared to what's already in the mash.  Seems like this would have no flavor impact on the finished beer.   What's the advantage of using slaked lime to remove bicarbonates instead?  Seems like a lot of work (precipitating the chalk overnight, racking off of it) for a process that also removes Calcium.
Title: Re: Acidifying the mash
Post by: tschmidlin on April 08, 2011, 06:02:02 AM
So, using phosphoric acid results in an insignificant amount of phosphate compared to what's already in the mash.  Seems like this would have no flavor impact on the finished beer.   What's the advantage of using slaked lime to remove bicarbonates instead?  Seems like a lot of work (precipitating the chalk overnight, racking off of it) for a process that also removes Calcium.
I'm not sure I understand your question . . . you would use them for different reasons.  Adding phosphoric acid will drop the pH.  Adding slaked lime will raise it.

Slaked lime is calcium hydroxide, so you are adding calcium anyway.  If the increase in pH precipitates CaCO3, well, one of the water chemists can probably explain if there is a net increase/decrease/no change in the amount of calcium, I don't know. :-\
Title: Re: Acidifying the mash
Post by: gordonstrong on April 08, 2011, 12:53:12 PM
Slaked lime is sometimes used to precipitate temporary hardness from water.  It's an alternative to boiling.  I have horrible water, full of carbonates.  That's what I get for living on top of a huge chunk of limestone.  So I've tried all sorts of things, including both methods.  They take time, energy, and labor.  And they still aren't all that effective.  So I solve the problem by buying RO water.

I use phosphoric acid to adjust the pH of RO water.  Yes, adding lime to water with temporary hardness will lower pH because of the reactions that result in precipitate.  Just like adding gypsum to a mash lowers pH because of the reactions it causes.  But if you have RO water, there is nothing to react with.  The only way you lower pH is to add an acid.

So I add an acid when I want to lower the pH.  If I wanted to change the mineral content, then I'd do something else.

I'm more interested in engineering beer than engineering water.  What happens along the way is of less concern to me as long as the outcome is something I can predict and control.
Title: Re: Acidifying the mash
Post by: mabrungard on April 08, 2011, 04:26:01 PM
So, using phosphoric acid results in an insignificant amount of phosphate compared to what's already in the mash.  Seems like this would have no flavor impact on the finished beer.   What's the advantage of using slaked lime to remove bicarbonates instead?  Seems like a lot of work (precipitating the chalk overnight, racking off of it) for a process that also removes Calcium.

Slaked Lime actually significantly increases water alkalinity initially.  It is added to increase the pH of the water to above 10 where calcium carbonate becomes insoluble.  Increasing the pH to above 11 will also reduce the solubility of magnesium.  That undesirable hardness precipitates out of solution and the clear water is decanted off the sediment.  

That clear water still has significant alkalinity.  Either CO2 is bubbled through the water to help reduce the water pH (it adds carbonic acid) or an acid such as hydrochloric, sulfuric, phosphoric, or lactic is added to bring the pH (and alkalinity) to a reasonable level.  

This process is only partially effective at removing calcium or magnesium.  If the water had mostly temporary hardness, you can typically only bring the Ca to 30 ppm and the Mg to 10 ppm with Lime softening.  If it has a lot or permanent hardness, then the Ca and Mg will be higher.

Phosphororic acid is relatively tasteless in beer for the reason you cite.  

Unlike Gordon, I am interested in both engineering water and beer.  In both cases, they are my profession.
Title: Re: Acidifying the mash
Post by: narvin on April 09, 2011, 06:20:00 AM
I'm really just looking for alternatives to carting home 15 gallons of RO water when I want to brew a pilsner.  It's mostly the bicarbonates I want to eliminate, since the other mineral levels are fine for a German pils.  I have 10% phosphoric acid that I bought from NB a few years ago... never used it much thanks to some "advice" that's been going around  :)