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General Category => General Homebrew Discussion => Topic started by: Wort-H.O.G. on February 26, 2013, 02:18:48 PM

Title: Lactic Acid Impact on flavour
Post by: Wort-H.O.G. on February 26, 2013, 02:18:48 PM
Does anyone have any experience with lactic acid additions for lowering mash PH, and at what levels it imparts a noticeable taste attribute in the beer?

Ive read its a more subtle and smooth acid, but i'm curious as how much you can use before you might perceive it in a beer - especially beers where a tartness our sour tang is not desired.
Title: Re: Lactic Acid Impact on flavour
Post by: kramerog on February 26, 2013, 02:31:53 PM
If you are using lactic acid to get the mash pH in range, I doubt you will ever notice it.  If the ultimate beer is within normal pH range, I doubt you will notice any lactic acid additions.
Title: Re: Lactic Acid Impact on flavour
Post by: redbeerman on February 26, 2013, 03:20:13 PM
If you are using lactic acid to get the mash pH in range, I doubt you will ever notice it.  If the ultimate beer is within normal pH range, I doubt you will notice any lactic acid additions.

+1 You are only using the lactic acid to get in the pH range for starch conversion.  The concentration   would have to be much higher for you to pick up on it in the final beer.
Title: Re: Lactic Acid Impact on flavour
Post by: Wort-H.O.G. on February 26, 2013, 03:25:50 PM
If you are using lactic acid to get the mash pH in range, I doubt you will ever notice it.  If the ultimate beer is within normal pH range, I doubt you will notice any lactic acid additions.

+1 You are only using the lactic acid to get in the pH range for starch conversion.  The concentration   would have to be much higher for you to pick up on it in the final beer.

so mash additions of 2-5ml for a typical 5-gal recipe is negligible?
Title: Re: Lactic Acid Impact on flavour
Post by: redbeerman on February 26, 2013, 03:29:37 PM
If you are using lactic acid to get the mash pH in range, I doubt you will ever notice it.  If the ultimate beer is within normal pH range, I doubt you will notice any lactic acid additions.

+1 You are only using the lactic acid to get in the pH range for starch conversion.  The concentration   would have to be much higher for you to pick up on it in the final beer.

so mash additions of 2-5ml for a typical 5-gal recipe is negligible?

Yessir.  I have used both lactic acid and phosphoric acid additions.  Can't tell either are there.
Title: Re: Lactic Acid Impact on flavour
Post by: Kaiser on February 26, 2013, 04:03:44 PM
2-5 ml for a 5 gal batch should be fine. this comes out to about 1-3% equivalent amount of acidulated malt.

The concern with too much lactic acid to get to the proper mash pH is that there might be too much lactate in the final beer. But you'll be fine with less than 4% acidulated malt equivalent. There is not much data available on this and this 4-5% limit is what many home brewers go by.

Kai
Title: Re: Lactic Acid Impact on flavour
Post by: Wort-H.O.G. on February 26, 2013, 04:12:13 PM
2-5 ml for a 5 gal batch should be fine. this comes out to about 1-3% equivalent amount of acidulated malt.

The concern with too much lactic acid to get to the proper mash pH is that there might be too much lactate in the final beer. But you'll be fine with less than 4% acidulated malt equivalent. There is not much data available on this and this 4-5% limit is what many home brewers go by.

Kai

Kai- exactly what I was looking for...upper limit thresholds.  before i switched over to distilled water, i had to add around 8-10ml lactic acid due to my well water profile. that would put me over the 4-5% for sure.
Title: Re: Lactic Acid Impact on flavour
Post by: Kaiser on February 26, 2013, 04:23:13 PM
Yes, very alkaline well water will require lots of acid. That's why it is recommended to remove alkalinity from such waters (through decarbonation or dilution) even if acid will still be needed to get the mash pH down.

another source of acid is sparge water acidification.

That's why I added reporting of equivalent grist acidulated malt % to the Brewer's Friend Water calculator.

Kai
Title: Re: Lactic Acid Impact on flavour
Post by: yso191 on February 26, 2013, 04:27:47 PM
Somewhere in my studies I came across this info and wrote it on my cheatsheet:

"1 ml lactic acid per gal max: 400 ppm flavor threshold (6.5 Ml in 5 galllons of BEER is the flavor threshold) so preboiled wort must be less"

FWIW
Title: Re: Lactic Acid Impact on flavour
Post by: kramerog on February 26, 2013, 04:48:12 PM
Somewhere in my studies I came across this info and wrote it on my cheatsheet:

"1 ml lactic acid per gal max: 400 ppm flavor threshold (6.5 Ml in 5 galllons of BEER is the flavor threshold) so preboiled wort must be less"

FWIW

Is that the taste threshold in water or beer and what kind of beer?  I've used 5 ml / 5 gal in mashes in the past without noticing a taste impact.  FWIW, I generally do not need to use any acids to adjust my mash pH.  I have also not discerned any taste change when adding 5 ml to 5 gal of finished wit in an attempt to get a little sourness, but did notice a change when adding 10 ml.
Title: Re: Lactic Acid Impact on flavour
Post by: yso191 on February 26, 2013, 05:33:45 PM
Somewhere in my studies I came across this info and wrote it on my cheatsheet:

"1 ml lactic acid per gal max: 400 ppm flavor threshold (6.5 Ml in 5 galllons of BEER is the flavor threshold) so preboiled wort must be less"

FWIW

Is that the taste threshold in water or beer and what kind of beer?  I've used 5 ml / 5 gal in mashes in the past without noticing a taste impact.  FWIW, I generally do not need to use any acids to adjust my mash pH.  I have also not discerned any taste change when adding 5 ml to 5 gal of finished wit in an attempt to get a little sourness, but did notice a change when adding 10 ml.

When I wrote the note to myself it was to provide a boundary for me - just knowing where I'd be safe.  Your experience bears out what I understand.  And yes it was in beer (the finished product) not water, but I don't know that there would be a difference.  I also don't know that the type of beer makes any difference, though it seems intuitive that a very light beer would show it more quickly than a more full-flavored beer.

I also would think that when using lactic acid in a mash some of it will be left behind with the grain, and not end up in the boil kettle.  But I don't have the ability nor inclination to do the calculation.  It is enough for me to know that for a 5 gallon batch I can use up to 5 ml of lactic acid in the mash to drop the pH without negative impact.
Title: Re: Lactic Acid Impact on flavour
Post by: Kaiser on February 26, 2013, 05:43:04 PM
I have seen that 400 mg/l number before and think that it probably applies to light lager of general strength (12 Plato). I think the taste threshold is certainly affected by the gravity of the beer and other characteristics. (IBUs come to mind).

Kai
Title: Re: Lactic Acid Impact on flavour
Post by: Wort-H.O.G. on February 26, 2013, 05:56:33 PM
I have seen that 400 mg/l number before and think that it probably applies to light lager of general strength (12 Plato). I think the taste threshold is certainly affected by the gravity of the beer and other characteristics. (IBUs come to mind).

Kai

this is all interesting. i have two pale ales in kegs - both about 1.057 OG. one was well water using 10mg lactic acid in mash to adjust ph to 5.4, and the other with distilled using just 1ml lactic acid to adjust to ph of 5.4. there is a definite twang to the 10ml lactic acid beer, and im starting to think after all this discussion that it was impacted by the higher concentration of lactic acid.
Title: Re: Lactic Acid Impact on flavour
Post by: davidgzach on February 26, 2013, 06:24:06 PM
I have seen that 400 mg/l number before and think that it probably applies to light lager of general strength (12 Plato). I think the taste threshold is certainly affected by the gravity of the beer and other characteristics. (IBUs come to mind).

Kai

this is all interesting. i have two pale ales in kegs - both about 1.057 OG. one was well water using 10mg lactic acid in mash to adjust ph to 5.4, and the other with distilled using just 1ml lactic acid to adjust to ph of 5.4. there is a definite twang to the 10ml lactic acid beer, and im starting to think after all this discussion that it was impacted by the higher concentration of lactic acid.

Same yeast?
Title: Re: Lactic Acid Impact on flavour
Post by: Wort-H.O.G. on February 26, 2013, 06:33:20 PM
I have seen that 400 mg/l number before and think that it probably applies to light lager of general strength (12 Plato). I think the taste threshold is certainly affected by the gravity of the beer and other characteristics. (IBUs come to mind).

Kai

this is all interesting. i have two pale ales in kegs - both about 1.057 OG. one was well water using 10mg lactic acid in mash to adjust ph to 5.4, and the other with distilled using just 1ml lactic acid to adjust to ph of 5.4. there is a definite twang to the 10ml lactic acid beer, and im starting to think after all this discussion that it was impacted by the higher concentration of lactic acid.

Same yeast?

correct wlp007 and both about 34 ibu  using same hop schedule of fuggle and ek goldings dry hops.
Title: Re: Lactic Acid Impact on flavour
Post by: davidgzach on February 26, 2013, 07:47:17 PM
That's interesting.  10ml is a good amount.  I used 5ml the other day in my Hefe.  I'll remember to try and perceive any twang to it.

Dave
Title: Re: Lactic Acid Impact on flavour
Post by: Wort-H.O.G. on February 26, 2013, 07:57:07 PM
That's interesting.  10ml is a good amount.  I used 5ml the other day in my Hefe.  I'll remember to try and perceive any twang to it.

Dave

it was in the back of my mind as the culprit, and why i asked the question about the amount threshold. im guilty of not even thinking 10ML would have and perceivable tastes in roughly 8 gallons of mash water. seems like such a small amount.
Title: Re: Lactic Acid Impact on flavour
Post by: mabrungard on February 26, 2013, 08:24:46 PM
The 400 ppm taste threshold for lactic in beer was presented in Malting and Brewing Science.  The important things to remember is that this is the median response in humans, some may detect it at lower concentrations. In addition, malt and yeast also contribute lactic acid to the beer.  Malting and Brewing Science indicates somewhere in the range of 200 to 300 ppm is contributed by those sources.  Therefore you can't just add the equivalent of 400 ppm lactic acid to a beer or the water.  The allowable amount will be less.  I've suggested that limiting the lactic acid addition to produce 200 ppm or less concentration is wise. 

Since lactic acid is a monovalent acid, for every 1 ppm of bicarbonate you neutralize with that acid, 1 ppm of lactate is added to the wort or water.  So using the Bru'n Water calculator, you can quickly see what you are adding to the mash water since the acid addition shows up as a negative Bicarbonate addition.  Keep that value below -200 ppm and you should be good.  It turns out that for 88% lactic acid, that equates to about 1 to 1.1 mL acid per gallon of water.  So 5 mL in 5 gal is safe.  10 mL is probably pushing it.

PS: Lactic flavor can be a pleasant component in some beer styles, so don't fret if you exceed this limit.  For instance, doubling that safe 1 to 1.1 mL per gallon dose should produce a notable lactic taste.  Good for Wits, Berliners, etc.
Title: Re: Lactic Acid Impact on flavour
Post by: Wort-H.O.G. on February 26, 2013, 08:44:23 PM
The 400 ppm taste threshold for lactic in beer was presented in Malting and Brewing Science.  The important things to remember is that this is the median response in humans, some may detect it at lower concentrations. In addition, malt and yeast also contribute lactic acid to the beer.  Malting and Brewing Science indicates somewhere in the range of 200 to 300 ppm is contributed by those sources.  Therefore you can't just add the equivalent of 400 ppm lactic acid to a beer or the water.  The allowable amount will be less.  I've suggested that limiting the lactic acid addition to produce 200 ppm or less concentration is wise. 

Since lactic acid is a monovalent acid, for every 1 ppm of bicarbonate you neutralize with that acid, 1 ppm of lactate is added to the wort or water.  So using the Bru'n Water calculator, you can quickly see what you are adding to the mash water since the acid addition shows up as a negative Bicarbonate addition.  Keep that value below -200 ppm and you should be good.  It turns out that for 88% lactic acid, that equates to about 1 to 1.1 mL acid per gallon of water.  So 5 mL in 5 gal is safe.  10 mL is probably pushing it.

PS: Lactic flavor can be a pleasant component in some beer styles, so don't fret if you exceed this limit.  For instance, doubling that safe 1 to 1.1 mL per gallon should produce a notable lactic taste.  Good for Wits, Berliners, etc.

this has been a great "ahha" day!  using my well water (high bicarb and alkalinity), Bru'n water has required me to add about 10ml of lactic acid to 5.5 gallons of mash water to hit Ph of 5.2 -5.3.  for me, i can taste that in my pale ale and there is nothing good about that in this beer.  its time to install my RO system and my adjustments with lactic acid will be minimal, at best. will also take care of the sodium issue, so win win for me!

thanks everyone for help in the discovery today....i love this forum.
Title: Re: Lactic Acid Impact on flavour
Post by: redbeerman on February 27, 2013, 08:21:52 PM
You could also use phosphoric acid.  It is much cleaner.  I have the same issue, so I mix my well water with store bought spring water (it is low in mineral content).  Everything below 9 SRM requires a pH adjustment to the mash.
Title: Re: Lactic Acid Impact on flavour
Post by: Wort-H.O.G. on February 28, 2013, 01:18:35 AM
You could also use phosphoric acid.  It is much cleaner.  I have the same issue, so I mix my well water with store bought spring water (it is low in mineral content).  Everything below 9 SRM requires a pH adjustment to the mash.

I have never used phosphoric acid, and don't know how it impacts vs. lactic. I've just decided install RO system and minimize my acid additions based upon my acid contribution from the grain for the recipe. Even without crystal or roasted malt, I will only need 1-3 ml of acid at best to hit 5.2-5.3. Also, solves my sodium issue of 114 ppm in my well water.