Lactic Acid

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Is there anything to watch out for using lactic acid to reduce alkalinity?

I'm finally getting round to planning my first brew with the local St Albans tap water (Ca 145, Na 30, HCO3 333, SO4 42, Cl 55, NO3 31). I thought I'd aim for a 'London' profile in order to brew a Best Bitter style ale using WY1469 - comments are welcome as I'm still very new at this.

I need to get the alkalinity down, but it seems that doing this with just AMS might push the sulphate and chloride a bit high. So I think I need to use a combination of acids. I've heard phosphoric works well but I couldn't get any... however I've managed to get my hands on some un-perfumed 80% lactic.

IMG_5201.JPG


Bru'n water seems to suggest that adding roughly equal volumes of AMS and lactic will do the trick for the profile (see below); but has anyone else tried using it and is it likely to add any weird flavours or other effects? Thanks for any tips...

1603882277079.png
 
From this experiment on Brülosophy it seems that using lactic acid can at least produce drinkable beer...:laugh8:
Phosphoric did slightly better in the tests, but the concentrations were quite high.
I'm thinking of making up a small batch of water treated with my AMS + lactic and see if it tastes of anything... good idea?
 
Your lactic acid looks an odd colour, its always been clear for me.

That aside, there is a flavour threshold for lactic acid. Most of the time this isn't a problem and sometimes can be pleasant in some beers, but it may be unwanted in others and some yeasts are lactic acid producers so the two combined can make the lactate obvious in taste.

I have taken to mashing at 5.4 pH for most beers now, then adding additional acid just before copper finings to get the wort to 5.0 5.1 or thereabouts as the finings work better there, but you get better hop utilisation at higher pH. Like most things in brewing you always have to compromise.
 
I exclusively use lactic and have never noticed the taste but then I start with Ashbeck so the amounts I add are minimal. The most being 0.14ml/l of 80% strength to an EBC 5.7 lager.

Brunwater will tell you on the Adjustment Summary page what the ppm lactate addition is and whether it's expected to be under the taste threshold.
 
Are you sure that lactic acid is food grade? Isn't Origins a cosmetics company?
 
Isn't Origins a cosmetics company?
Good question Steve. In response to a question about whether the product is 'food grade', the seller said:

"we do not hold a food license, however, this product is 100% pure and does not have anything added to it.
We hope this assists."


Well I suppose one can read into that what one will... however given the pH it should be microbiologically safe, and at the dilutions I'm using it seems unlikely to introduce any significant chemical contamination.

My only concern was really whether it was perfumed; but there doesn't seem to be any odour to it so I'm hoping not.

What do you reckon?
 
My only concern was really whether it was perfumed; but there doesn't seem to be any odour to it so I'm hoping not.

What do you reckon
I'm not sure to be honest, but as @Hanglow says it looks an odd colour, lactic acid should be clear.

Regarding your first post, I wouldn't be at all concerned about using AMS for a bitter, especially with your starting profile.

If I'm reading your screenshot correctly it looks like the target profile is 70 calcium, 40 sulphate, 38 sulphate, and 168 bicarbonate? That's not a great profile for a bitter in my opinion. I'd be looking for something more like this personally (note this may not be possible depending on the staring profile, but something along these lines would be an improvement):
150 calcium
250 sulphate
130 chloride
35 alkalinity
 
something along these lines would be an improvement: Ca 150, SO4 250, Cl 130, ALK 35
Thanks @strange-steve that's really helpful.

OK two options (both with an estimated mash pH of around 5.2): [update: I can do better than this - see below]
  1. Ca 164, Mg 10, Na 32, SO4 193, Cl 96 (1.3ml CRS, 0.08g gypsum, 0.1g epsom)
  2. Ca 216, Mg 10, Na 32, SO4 251, Cl 133 (1.1ml CRS, 0.2g gypsum, 0.1g epsom, 0.09 CaCl2)
Which would you prefer? The first matches your sulphate/chloride ratio but with lower ppm, and approximates the calcium; the second is a lot closer but pushes the Ca (I could increase the Na or Mg instead I guess).
 
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OK, by combining acids I can get closer. With 1ml CRS, 0.11ml lactic (80%), 0.1g gypsum, 0.1g epsom I get Ca 168, Mg 10, Na 32, SO4 247, Cl 127 (and ALK 35)

For what it's worth my approach was:
  1. add CRS to hit the desired chloride
  2. add lactic until the bicarbonate is correct
  3. add a bit of epsom to get some sulphate without introducing too much Mg
  4. make up the rest of the sulphate with gypsum while keeping an eye on the Ca
I can see that Bru'n Water's "Mashing Water Profile" is different to the "Finished Water Profile"... I guess it's because it lets me use a different treatment for the sparging water - but I'm not sure why I would want to do that...?
 
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I'm with Steve on this, I don't see any reason why you wouldn't just use AMS/CRS. On its own it'll give you the slight sulphate balance. The amount of sulphate/chloride in the finished beer will at least double what you're adding anyway.
 
I should have clarified, when I said 35 ppm alkalinity that was as CaCO3, which is ~43 ppm bicarbonate, and that is only an estimate. Since you're using software, target a bicarbonate level to hit a pH of about 5.4
 
I'm with Steve on this, I don't see any reason why you wouldn't just use AMS/CRS.
Cheers Jocky ... to be honest I feel like Mickey Mouse in 'Fantasia', messing with magic I don't understand :laugh8:
The only reason I'm now planning to use some lactic is because (according to Bru'n Water, at least) it lets me get closer to the profile he recommends without taking the calcium so high - but what would you recommend with my water?

1603908282728.png
 
I should have clarified, when I said 35 ppm alkalinity that was as CaCO3, which is ~43 ppm bicarbonate, and that is only an estimate. Since you're using software, target a bicarbonate level to hit a pH of about 5.4
Yeah, that's OK Steve, I worked out that in order to achieve the 35ppm ALK I needed to make the Bicarb 43ppm, and then I played with the Na/Mg to balance the ions (gee, listen to me trying to sound like I know what I'm taking about...)

My water adjustment sheet looks like this:
072c1741-4771-4935-a89d-83c5142ff96f_l.png
 
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Yeah, that's OK Steve, I worked out that in order to achieve the 35ppm ALK I needed to make the Bicarb 43ppm, and then I played with the Na/Mg to balance the ions (gee, listen to me trying to sound like I know what I'm taking about...)

My water adjustment sheet looks like this:
072c1741-4771-4935-a89d-83c5142ff96f_l.png
That looks like a fairly decent bitter profile to me. My only observation would be that the estimated pH is a touch low, I'd prefer about 5.4 personally.
 
That looks like a fairly decent bitter profile to me. My only observation would be that the estimated pH is a touch low, I'd prefer about 5.4 personally.
You're right... and so is @JockyBrewer (thanks both)
If I remove the lactic completely from both the mash and the sparge, I now get this (which gives me the pH bang on 5.4) athumb..

da1465ed-9076-451b-8a3d-1bad90c79763_l.png
 
Hate to derail but is there any reason not to use citric acid, either in this recipe or generally, if you don't want to add extra sulphates and chlorides?
 
That looks good. I don't think you need to worry about the level of ions treating your water with CRS/AMS exclusively, BnW is quite conservative compared to British brewing practices.

The ions are on the high side, but far from excessive. My water supply alkalinity is normally around 250ppm as CaCO3, which leaves me with around 300ppm bicarbonate and around 115ppm calcium, and I've had as much as 300ppm chloride (AMS treatment + some calcium chloride in the kettle) in a gold medal winning stout.

Obsessing over water profiles doesn't really matter until you have a fairly set recipe that you can brew repeatedly, and even then it's a relatively minor tweak.
 
Hate to derail but is there any reason not to use citric acid, either in this recipe or generally, if you don't want to add extra sulphates and chlorides?

You need quite a lot of citric or lactic acid to treat British water generally (unless you live in one of the less common soft water areas), and it will go above the taste threshold quite easily. Overall you can add much more AMS/CRS before it becomes a problem. I'm yet to meet or hear of anyone that says they added an amount of AMS/CRS to the point that they could taste it in the water, whereas I have with lactic acid (several times), and I think that citric would be an even more extreme than that.

There's really no good reason to use citric or lactic acid when AMS/CRS is available.
 
I have thought about treating my water with citric acid before in a fruity pale ale. It might go with that, otherwise I think it would taste a bit odd. Probably not as bad as using acetic though!

If you really want to get into acidification, look into making a sauergut reactor. Biological acidification has other benefits (as well as being reinheitsgebot compliant), plus if you like good german beers it's one of those elusive essential flavours you get in some of the better ones.
 
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