Lactic acid for lowering mash ph?

The Homebrew Forum

Help Support The Homebrew Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Monkhouse

Regular.
Joined
Nov 3, 2017
Messages
424
Reaction score
136
Location
Carnforth, sleepy old town in the northwest
I use Brewfather as my go to software nowadays but it only offers lactic acid and phosphoric acid as a means to lower PH.
Ive looked for both and the only one malt miller stocks is lactic acid 80%. Brewfather only calls for a small amount circa 5ml for my full batch (belgian tripel).
Is lactic acid suitable?
All I think about when I hear lactic acid is lactobacillus, then I think about nasty ass sour beer…then I get doubting things!
The last thing I want is sour beer!
Any advice?
 
Using lactic acid to adjust pH is completely fine, lots of people use it although I must admit I use AMS/CRS instead (also available from the Malt Miller). Primary reason for me being that I have quite high alkalinity water and as I understand it, lactic acid can add some undesirable flavours to your beer if used in high quantities.
 
Lactic can give a acid taste if too much is used and thats why some use phosohoric as it is less likely to do this. I prefer to use Lactic Acid grain but when I have used liquid Lactic I use about 5ml in a 21ltr brew and this is well under the threshold for throwing any acid taste
 
Last edited:
I use lactic acid to adjust mash pH. I haven't found an acid taste at the levels I use (typically 5-6 ml). My process is to add about 75% of the lactic acid required to the mash liquor, mash in my grain and then check pH after 15 minutes.

I also use AMS/CRS to reduce the alkalinity of my liquor first. Doing this means you need less lactic acid to reduce your mash pH.
 
Given that normal fermentation produces enough lactic acid to drop pH to c4.0, do lactic acid mash adjustments produce a taste, or is it just one of those easily repeated myths?
 
Given that normal fermentation produces enough lactic acid to drop pH to c4.0,do lactic acid mash adjustments produce a taste, or is it just one of those easily repeated myths?
No, that's nonsense and not a myth. You want the mash pH to be controlled for enzymatic activity, which happens way before the boil, which happens way before fermention

Maybe try reading up on the science of brewing to give you a beginner's guide to what's happening at each stage of the brewing process.
 
No, that's nonsense and not a myth. You want the mash pH to be controlled for enzymatic activity, which happens way before the boil, which happens way before fermention

Maybe try reading up on the science of brewing to give you a beginner's guide to what's happening at each stage of the brewing process.
Eh? Tipsy? Perhaps read the above article regarding lactic acid flavour threshold.

The end point is beer containing enough lactic acid to help shift ph considerably down the logarithmic ph scale to c4.0, either by addition or fermentation. Would the small amount added in the mash to c5.4 ph be tasted over the larger amounts of organic acids added by yeast? Does anyone ever add enough to breach that flavour threshold or use water high enough in alkalinity to require it?
 
Last edited:
Does anyone ever add enough to breach that flavour threshold or use water high enough in alkalinity to require it?

Yes....in the early days of my all grain brewing with our local tap water being classed as VERY hard I was using on occasion maybe 10-12mL of lactic for a 20L brew. I went for a period of competition entries where judges were commenting on a slightly acidic twang to the beers which I had also noticed but didnt put my finger on what was the cause.

When I switched to using Tesco Ashbeck (either in isolation or to dilute my tap water) and started needing to add only 2-5mL of lactic then the flavour issues disappeared.
 
Lactic acid or phosphoric acid are fine overdoing with either will put it in the taste threshold, part of the taste in Coca Cola is due to the phosphoric acid.

How much acid are you using in RO water?
Depending on style (usually bitters & wheats) and other salts, I use between 7-22ml treating 80L liquor for a 60L batch, which is very low and way below the Braukaiser threshold. I aim to get the liquor in the 5.5-6.0 pH range.
 

Latest posts

Back
Top