Adjusting pH with lactic acid

Discussion in 'General Brewing Discussions' started by Christopher Brown, Mar 14, 2019.

  1. Christopher Brown

    Christopher Brown New Member

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    Does lactic acid make your beer sour?
     
  2. Nosybear

    Nosybear Well-Known Member

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    It does, if you use enough of it. As a water adjustment, no. But you can make a tart beer if you add enough of it.
     
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  3. Christopher Brown

    Christopher Brown New Member

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    Just trying to bring my beer from 5.8 pH to 5.4
     
  4. J A

    J A Well-Known Member

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    You won't add much to get that adjustment. You'd never taste it. If you're concerned you can use phosphoric acid which is flavorless.
     
  5. Nosybear

    Nosybear Well-Known Member

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    If you've already boiled it, don't do anything yet. Sample it before you package and if it has a lifeless flavor, add acid to taste.
     
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  6. Craigerrr

    Craigerrr Well-Known Member

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    I typically add X amount of lactic to my total water volume before heating up to strike temperature, based on the water calculator results to get to the desired mash temp.
     
  7. Yooper

    Yooper Administrator
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    It depends on your water, and the amount you're using. As an experiment, I took my sparge water and added enough lactic acid to bring the sparge pH to under 6. It ended up being about 1 ml per gallon that I had to use. Then, I tasted the water. At that amount in my water source, I could not taste anything at all except water.

    You could try that with your source water, but in my case I can easily use 1 ml per gallon without reaching the taste threshold.
     
  8. Conchobar

    Conchobar New Member

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  9. Conchobar

    Conchobar New Member

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    I read somewhere, probably here, that lactic acid should be kept under 5% or you begin to detect the taste.
     
  10. Yooper

    Yooper Administrator
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    I think what I “know” is that 3% of the grainbill as acidulated malt is not detectable, or at least it’s not detectable as tangy, and instead maybe just a depth of flavor, but I don’t know about the 5% of lactic acid.

    If you have RO water and add 5% lactic acid, I would be willing to bet you could taste it.
     
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  11. Nosybear

    Nosybear Well-Known Member

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    Lactic acid add (assuming 88% lactic acid solution) for water adjustment is down in the milliliter range. If you want to acidifiy a beer, say a Gose, you want the flavor. I assume with 5% you're talking about acidulated malt? I add up to 5% of the grain bill as acidulated at times and have never noticed tanginess, maybe just a hint of refreshing tartness....
     
  12. J A

    J A Well-Known Member

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    Since the OP has mentioned "beer" instead of wort he may be wanting to add directly to a finished beer? I added about a teaspoon and a half to a refermented beer to create a sour and it was enough to impart a light, definite sour flavor but not a really tart sour. That's a rate of less than 1.5 ml per gallon but I didn't measure the ph. There should be a chart or calculator to tell you exactly what your per-gallom requirement would be to lower the PH by .4.
     
  13. Nosybear

    Nosybear Well-Known Member

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    pH on finished, uncarbonated beers is generally somewhere in the neighborhood of 4.2. Sours are generally somewhere south of 3.8 but since the pH scale is logarithmic, that's a lot more acid than 4.2. The chart or calculator idea.... Complex. You could get it with titration but that requires some knowledge of chemistry. The best instrument for this is simply your tastebuds. Take a sample and add acid. If you like it better, add a proportional amount to the beer and resample. You can do this at packaging to "tweak" the outcome even if it isn't sourness you want.
     
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  14. Conchobar

    Conchobar New Member

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    Are you using gypsum or calcium chloride or just lactic acid?
     
  15. I_playdrums

    I_playdrums Well-Known Member

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    Buy a ph meter for the best accuracy. Online calculators are merely a suggestion.
     
  16. J A

    J A Well-Known Member

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    When I made my comments, I wasn't thinking about the numbers...at 5.8, of course the OP must be referencing wort and not beer.
    @Christopher Brown, I bring my sparge water down at least that much with less than .5ml per gallon - far less than the flavor threshold.
     

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