Lactic Acid Taste Threshold

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pacebrew

Well-Known Member
I was wondering if anyone knows, as a general rule, how many mililiters of lactic acid / x gallons, gives off a notable taste.

Im trying to lower my RA, and was wondering if anyone has any experience with this. THanks.

GilaMinumBeer

Half-fast Prattlarian
400 ppm is the taste threshold.

Lambics have anywhere from 492 to 3600ppm.

OP
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pacebrew

Well-Known Member
What does that equate to in ml/gal?

GilaMinumBeer

Half-fast Prattlarian
ppm is mg/l so you need to convert from mg/l to ml/gal. Not sure how. don;t have time to look it up.

remilard

Well-Known Member
One question you should ask yourself is, do you want to be below the flavor threshold? Lactic acid doesn't taste entirely unpleasant and where the taste threshold is and where the drinker would detect sourness are two different places.

OP
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pacebrew

Well-Known Member
im adding maybe at most 5 ml to ~5 gallons.. i dont think i will have an issue, yea, for some beers it could even be beneficial. thanks for everyones input.

GilaMinumBeer

Half-fast Prattlarian
Trouble is, you need the density of Lactic acid to make a conversion from mass to volume for calculations. I can't find it. and then the concentration will play into that as well.

dstar26t

If it's worth doing, it's worth overdoing
Density of lactic acid is 1.21 Kg/L.

So 400ppm equates to 1.25mL/gal. Please correct me if I'm wrong.

rocketman768

Well-Known Member
Density of lactic acid is 1.21 Kg/L.

So 400ppm equates to 1.25mL/gal. Please correct me if I'm wrong.
Except he's probably not using 100% lactic acid. Also, why do you want to use lactic acid over, say, phosphoric acid which has no sour taste?

dstar26t

If it's worth doing, it's worth overdoing
The density I posted is for common 88% lactic acid. Phosphoric acid precipitates calcium which screws up the mineral profile you've worked to get. I don't know how much calcium but John Palmer mentioned it before.

tonymark

Well-Known Member
I know this is an old thread, but I was trying to figure all this out myself.

Density of lactic acid is 1.21 Kg/L.

So 400ppm equates to 1.25mL/gal. Please correct me if I'm wrong.
Almost, the density of the lactic solution is 1.21 kg/l (1210 mg/ml), but the solution is only 88% lactic acid. So the 400ppm comes out to 1.42 ml/gal of the solution.

brewitall

Supporting Member
HBT Supporter
"Also, why do you want to use lactic acid over, say, phosphoric acid which has no sour taste?"

Phosphoric acid is definitely detectable and will alter the flavor of your beer. It's one of the primary tastes in Coke. I've found 10ml of 88% in the mash isn't noticeable, 20ml is noticeable but not necessarily bad, and more than that can negatively affect the finished beer.

Silver_Is_Money

Larry Sayre, Developer of 'Mash Made Easy'
Often times I think people confuse the taste one derives from Lactobacillus (the bacteria required to sour a beer such as a Lambic) with 88% Lactic Acid. There is no Lactobacillus present in Lactic Acid.

Brulosophy added 19 ml of 88% Lactic Acid to a 5 gallon batch, and as a consequence they mashed it at pH 4.45, and did so side by side with an identical batch that did not get any added lactic acid, and was mashed at pH 5.30, and in the end a panel of blind taste testers could not distinguish between them.

To me this indicates two things.

1) 19 ml of 88% lactic acid in a batch sized for 5 gallons at the finish is not detectable.
2) Mashing at an unbelievably low measured pH of 4.45 caused no ill effects to the fermentation or the resulting beer.

Lastly, both beers finished fermenting at the same pH. The yeast made this happen.

Jayjay1976

Bubblegazer
HBT Supporter
Often times I think people confuse the taste one derives from Lactobacillus (the bacteria required to sour a beer such as a Lambic) with 88% Lactic Acid. There is no Lactobacillus present in Lactic Acid.

Brulosophy added 19 ml of 88% Lactic Acid to a 5 gallon batch, and as a consequence they mashed it at pH 4.45, and did so side by side with an identical batch that did not get any added lactic acid, and was mashed at pH 5.30, and in the end a panel of blind taste testers could not distinguish between them.

To me this indicates two things.

1) 19 ml of 88% lactic acid in a batch sized for 5 gallons at the finish is not detectable.
2) Mashing at an unbelievably low measured pH of 4.45 caused no ill effects to the fermentation or the resulting beer.

Lastly, both beers finished fermenting at the same pH. The yeast made this happen.
Could this mean that mash pH isn't as important as it is frequently made out to be?
If so, this is excellent news. I bought a pH meter but absolutely dread using it.

isomerization

Well-Known Member
Could this mean that mash pH isn't as important as it is frequently made out to be?
If so, this is excellent news. I bought a pH meter but absolutely dread using it.
If you use RO water with BruN water spreadsheet, it is spot on pretty much every time (for me at least).

Jayjay1976

Bubblegazer
HBT Supporter
If you use RO water with BruN water spreadsheet, it is spot on pretty much every time (for me at least).
I've found that Bru'N water requires opposable thumbs. I ain't got those. So I use the water calc on brewersfriend.com.

So many home brewers start with straight RO, I dunno why there isn't a list of water recipes ready to go with additions stated per gallon so us simpletons can make decent water. I'm freaking tired of going into a water calc and playing centipede to try and hit all of the goddamned PPM at once before my attention span expires..
WTF?

isomerization

Well-Known Member
I've found that Bru'N water requires opposable thumbs. I ain't got those. So I use the water calc on brewersfriend.com.

So many home brewers start with straight RO, I dunno why there isn't a list of water recipes ready to go with additions stated per gallon so us simpletons can make decent water. I'm freaking tired of going into a water calc and playing centipede to try and hit all of the goddamned PPM at once before my attention span expires..
WTF?
It’s honestly not that hard, especially when using RO. Think of them more as ranges anyway. If something calls for 150 pm of Cl, shoot for 140-160.

Jayjay1976

Bubblegazer
HBT Supporter
I'm usually able to get pretty close to all of the parameters except HCO. That one is always WAAY off and I don't know what to do to fix it. Why does this require a decoder ring?

day_trippr

Moderna Or Bust! :D
Which direction "waay off"? And what are you starting with for base water?
I just looked at my last Bru'n Water sheet (it's for the raspberry hibiscus wheat simmering in primary right now) and my HCO was like negative -90, while all other metrics were pretty much nailed:

As should be evident, I started with my RO water, but I'm not sure that matters wrt HCO, which you can knock out one way or the other is desired.
Imo, the less HCO the better, unless you're brewing something reaaaally acrid...

Cheers!

isomerization

Well-Known Member
I'm usually able to get pretty close to all of the parameters except HCO. That one is always WAAY off and I don't know what to do to fix it. Why does this require a decoder ring?
HCO is not a target, literally ignore it with RO water. Basically it’s a representation of the buffering power of your water.

I see where your frustration comes from now, like rolling a stone up a hill...

HBT Supporter

Kaspersound

Member
I know this is an old thread, but I was trying to figure all this out myself.

Almost, the density of the lactic solution is 1.21 kg/l (1210 mg/ml), but the solution is only 88% lactic acid. So the 400ppm comes out to 1.42 ml/gal of the solution.
Would it be possible to share the formula? I have 80% lactic acid solution... Would it be 1.53 ml/gal of 80% ?

Silver_Is_Money

Larry Sayre, Developer of 'Mash Made Easy'
When Kai Troester rounded up a number of his friends and tested for this via adding pH neutralized Lactic Acid to actual beers, he (and they) discovered that the age old threshold information was way off, and his team of testers could tolerate much higher addition levels before detecting it. Off the top of my head, the beer in which the quantity of Lactic Acid was highest before detection was "Bud Light". Kai attributed this to none of them knowing in advance what this beer actually tasted like when free of pH regulated Lactic Acid. That in itself has profound significance.

meaulnes2

New Member
Pure lactic acid weights 1.284 g / cm3 i.e. 1.284 g/ml
Volumic weight of diluted acid at 80% is probably less than 1.284 but we can approximate it to 1.25 g/ ml

Thus if we had X ml of lactic Acid 80% into 19 l (5 US Gal.)
we have X * 1.25 * 0.8 /19 g/l i.e. (X * 1.25 * 0.8 /19) g/l i.e X * 0.0526 g/ 1060 g (we approximate density of beer to 1.06)
i.,e. X * 0.0496 g /1000 g i.e X *49.6 ppm

Thus X for 400 ppm is 400 /49.6= 8.06 (X being in ml)

400 ppm correspond to 8 ml into 5 US Gal.

Silver_Is_Money

Larry Sayre, Developer of 'Mash Made Easy'
Detection levels in beer and detection levels in water are like comparing apples and oranges.

thisone

Well-Known Member
I used 3 ml in a 2.75 gal batch and I could taste it, but barely. It was a light beer (Pre Prohibition Lager) and only noticeable once it warmed up a bit. It wasn’t unpleasant though, I would just cut back a little bit more next time because it’s not the flavor I’m going for. 2 ml is undetectable imo but I’m curious if 2.5 ml is fine too

I’ve gotten much better results with my light beers once I’ve started using lactic acid to adjust the ph

Silver_Is_Money

Larry Sayre, Developer of 'Mash Made Easy'
ppm is mg/l so you need to convert from mg/l to ml/gal. Not sure how. don;t have time to look it up.
ppm is not mg/L

1 ppm = 1 unit of weight per 1 million units of weight (or in common parlance, weight per unit weight)
1 mg/L = 1 mg of weight per 1 Liter of volume (or in common parlance, weight per unit volume)

ppm is close to mg/L only for the case of deionized water at 4 degrees C.

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Silver_Is_Money

Larry Sayre, Developer of 'Mash Made Easy'
What does that equate to in ml/gal?
For 88% Lactic Acid it is ~1.43 mL/Gal.

meaulnes2

New Member
Detection levels in beer and detection levels in water are like comparing apples and oranges.
You are probably right, but my point was only to show that 400 ppm is far (despite many approximations) from 1.25 ml/US gal (dstar26t) or 1.42 ml/US gal (tonymark).
After that how this is detectable in beer probably varies a lot with the style and alcool of it.

Silver_Is_Money

Larry Sayre, Developer of 'Mash Made Easy'
For 88% Lactic Acid it is ~1.43 mL/Gal.
For 88% Lactic Acid:

sg = 1.209
density = 1.206 g/CC

88% x 1.206 g/mL = 1.06128 g/mL = 1,061,280 mg/L of pure Lactic Acid

400 mg/L / 1,061,280 mg/L = 0.000376903 L = 0.376903 mL

Therefore: 400 mg/L = 0.376903 mL of 88% Lactic Acid made up to 1 Liter via the addition of water

1 Gallon = 3.7854 Liters

So Therefore: 0.376903 mL x 3.7854 L/Gal. = 1.42673 mL/Gal.

Conclusion: 400 mg/L = 1.42673 mL of 88% Lactic Acid made up to 1 Gallon via the addition of water