# Lactic acid addition to mash - how much is too much?

How many ml of 88% lactic acid is it “ok” to add to your mash? I’m sure there is a top limit for safety reasons, let alone flavor reasons, but haven’t been able to find such limit anywhere.

Generally speaking you would only ever need to add a couple ml max – most of the time much less than that to your mash. You would need to use a water calculator or perform the calculations by hand to determine the amount required for your water and recipe combination (if any at all).

Obviously an 88% acid solution has toxic effects on humans and you certainly wouldn’t want to drink it or let children get at it.

http://www.sciencelab.com/msds.php?msdsId=9924446

The answer to “how much is too much” is simply the amount that brings your mash pH below your intended mash pH.

Taste thresholds vary. Some claim to be able to taste very small amounts added to the mash but unless they’ve been told that it’s in there it’s doubtful that they know.

If you ever have to add more than a couple ml then you might want to look into cutting your water with RO, RO/DI or distilled. Or better yet, buy a RO unit and get consistent water.

Finally, if you’re worried about the taste aspect, use phosphoric, sulfuric or hydrochloric.

Malting and Brewing Science quotes the taste threshold for lactic acid (lactate ion) is about 400 mg/L. As mentioned, that is the average threshold and it does vary between individuals.

I just updated the newest supporter’s version of Bru’n Water to include the resulting ion contributions for a bunch of acids including: lactic, acetic, malic, citric, tartaric, hydrochloric, sulfuric, and phosphoric. It calculates the ion concentration in both the sparge and mash and the final result in the kettle and reports if its above or below the typical taste threshold. That is a pretty handy result to those that have a neutralize a lot of alkalinity and probably near those taste thresholds. The program also includes the ability to use 2 acids in the mash and 2 in the sparge (up to 4 different acids) which should be useful to those battling a lot of alkalinity. This way, the brewer can hopefully keep all the acid additions below the taste thresholds and still produce decent beer with their tap water. The new version is just starting beta testing, so it will be a few weeks before its released to supporters.

Looking at the calculations for 88% lactic acid, it looks like an addition of less than 1.4 mL per gallon of water is likely to keep the lactate ion concentration below 400 mg/L.

Enjoy!

thanks guys. I added 7ml acid to the liquor.

[quote=“mabrungard”]Malting and Brewing Science quotes the taste threshold for lactic acid (lactate ion) is about 400 mg/L. As mentioned, that is the average threshold and it does vary between individuals.

I just updated the newest supporter’s version of Bru’n Water to include the resulting ion contributions for a bunch of acids including: lactic, acetic, malic, citric, tartaric, hydrochloric, sulfuric, and phosphoric. It calculates the ion concentration in both the sparge and mash and the final result in the kettle and reports if its above or below the typical taste threshold. That is a pretty handy result to those that have a neutralize a lot of alkalinity and probably near those taste thresholds. The program also includes the ability to use 2 acids in the mash and 2 in the sparge (up to 4 different acids) which should be useful to those battling a lot of alkalinity. This way, the brewer can hopefully keep all the acid additions below the taste thresholds and still produce decent beer with their tap water. The new version is just starting beta testing, so it will be a few weeks before its released to supporters.

Looking at the calculations for 88% lactic acid, it looks like an addition of less than 1.4 mL per gallon of water is likely to keep the lactate ion concentration below 400 mg/L.

Enjoy![/quote]
Martin, how do users of the supporter’s version get the new release?

It will be out in a few more weeks and will be directly sent to supporters that have contributed \$10 or more.

Well this begs the question, what happens to the folks you donated less than \$10? Can they submit an additional amount to makeup the difference? Or do they need to summit a new \$10 contribution?

thanks

tom

Any word on when the new Bru’N Water spreadsheet is going to be released?