Bringing pH down with lactic acid.

[kylexc]

Hi, everyone

I have been trying to accurately get my pH around 5.3 for most of my brews. I bought a Erickhill pH meter and bought some lactic acid 88% to play around with. Just one drop of lactic acid brings my gallon of RO water from 6.17ph to 5.36ph. I have done several gallon test which have come up with varying pH because of the size of the droplet. So next step is to use a eye dropper to get consistent smaller drops to get my desired range of pH. Note my RO Water pH has risen, which probably means I need to change the filters.

What was so confusing was reading about people using several grams of this stuff in small batch brews. I am testing with 1 gallon batches and for a week I have been thinking my tool wasn't working properly.

A couple odd things. Calibration takes about 7 minutes. It took Erickhill tool, 2 hours to get my house tap water of 8.05ph. This device is measures pretty quickly to 3-7ph range. I usually let the device sit in the solution I am measuring for 10minutes. Give it a couple of stairs in the solution as well. I will turn it off and on several times during the 10 minutes.

It seems very accurate.

Has anyone else experienced this kind of time delay to get a reading for pH? Should I leave it in the solution for certain amount of time? Anyone else using extremely small amount of lactic acid to get desired pH?

Thanks everyone, appreciate any wisdom.

Picture below are for fun.

 

[mac_1103]

RO water has almost no buffering capacity, so a very small acid addition will have a very large impact on pH and it can be very difficult to get a stable and accurate reading. The pH of your water isn't what matters, so stop trying to adjust the pH of your water. The pH of your mash is what's important, and the grains contribute lots of buffering capacity so larger additions may be needed to move the needle. Use software to predict the mash pH based on your starting water and grist, and add salts and acid (if needed) based on that prediction. Then take a sample of the mash about 15 minutes in, cool it to room temp and check the pH. Note and adjust the acid addition for the next brew if necessary.

 

[Bobby_M]

For emphasis, do not measure the pH of your water. It is meaningless and doesn't account for what the grain is going to do at all. Measure the mash liquor at 15 minutes, at room temperature. Yes, it will take more acid than that but it's dependent on the color of the beer.

 

[mabrungard]

To better understand what you're doing with acid and mineral additions, I recommend you visit this site and read: https://www.brunwater.com/water-knowledge

 

[kylexc]

Thank you everyone. Makes a lot more sense. I just haven't moved to the calculators because of the complexity it adds. Oh well.

 

[worlddivides]

Yes, for example, today I brewed a beer where I added 4 grams of lactic acid to about 20 liters of water (5.2 gallons). Together with the grains, the pH came down to about 5.27. But it's all the factors combined, with the grains in the mash being the biggest factor of them all.

 

[MaxStout]

Thank you everyone. Makes a lot more sense. I just haven't moved to the calculators because of the complexity it adds. Oh well.

Download the free Bru N Water spreadsheet. Its prediction model is quite good and it has a function for adding acids. It should help take out some of the complexity.

Every time I've used the program it's been within about .05 of my actual measurements.

 

[hottpeper13]

As for the time delay you mention, my meter flashes the reading until it is done. Takes about 10 seconds at most.

 

[Antbeer]

As for the time delay you mention, my meter flashes the reading until it is done. Takes about 10 seconds at most.

Thank you

 

[pfabsits]

To better understand what you're doing with acid and mineral additions, I recommend you visit this site and read: https://www.brunwater.com/water-knowledge

Hello Martin,

Back on the forum again. I use to be with Hanna and sent your a Halo BT meter. I am now with Milwaukee. I hope to connect in the future.

Paul

 

[mabrungard]

Paul! Good to see you back providing your expertise.

That Hanna Halo pH probe was a phenomenal unit and it served for quite a while. I couldn't justify replacing it in kind when replacing the SE220 probe on my MW-101 was so reasonably priced. The SE220 is a very durable and long-lived pH probe. Its what I routinely recommend, but I did extoll the virtues of the Halo too.