Problem with Brew Father and ph

[kurds_2408]

Hi. I am having a problem with my ph always coming out low. I am very new to water adjustments. The only thing I am doing currently is Sodium Metabisulphite for chlorine and lactic acid to lower ph. I’ve got pretty good water so just starting small. I started both these changes at the same time and have only been doing this for about 5-8 batches. Never did anything for a hundred batches before (I know, I am ashamed lol). I am currently using Brew Father to calculate. I got my water tested so I know exactly what the numbers are and put them into BF. I use an InkBird ph meter. My problem is I always end up around 4.7 to 5 following their recommendation for lactic acid. Obviously I could always just use less than recommended but would like to not have to guess. Does the Sodium Metabisulphite change ph? Cause I did notice that the recommended lactic acid doesn’t change if I change the amount of SM in the recipe. Wondering if that is where it messes up. Any help would be appreciated.

For reference my water ph is 7.8 and depending on recipe it has me 2-4ml of acid to it every time.

 

[Bobby_M]

I got my water tested so I know exactly what the numbers are and put them into BF.

A potential issue is that municipal water supplies can change as they switch between surface water and well sources (or a blend of the two). This is the main reason why I switched to an RO filter because spending $100 once is cheaper than getting water tested a couple times a year. Not only that, I have more flexibility in what my resulting water profile can be.

I use an InkBird ph meter.

I've come to accept that there's no free (or discount) lunch on pH meters and I'm suspect that a $50 meter can be accurate. Have you calibrated it by mixing the powdered buffer solution with an accurately measured out dose of distilled water? You can verify that it's calibrated correctly by buying some premixed buffer solution and seeing if the meter reads it correctly. Then after that hassle, just buy a Milwaukee MW102.

 

[micraftbeer]

I use Brewfather and add 88% landing acid based on recommendations. I would be shocked if 2-4 mL of acid (assuming you're using the same common 88%) got your pH that low.

I agree with @Bobby_M your meter sounds suspect. I also agree with his recommendation on the MW102. I've been using that baby for years!

 

[kurds_2408]

I use Brewfather and add 88% landing acid based on recommendations. I would be shocked if 2-4 mL of acid (assuming you're using the same common 88%) got your pH that low.

I agree with @Bobby_M your meter sounds suspect. I also agree with his recommendation on the MW102. I've been using that baby for years!

A potential issue is that municipal water supplies can change as they switch between surface water and well sources (or a blend of the two). This is the main reason why I switched to an RO filter because spending $100 once is cheaper than getting water tested a couple times a year. Not only that, I have more flexibility in what my resulting water profile can be.

I've come to accept that there's no free (or discount) lunch on pH meters and I'm suspect that a $50 meter can be accurate. Have you calibrated it by mixing the powdered buffer solution with an accurately measured out dose of distilled water? You can verify that it's calibrated correctly by buying some premixed buffer solution and seeing if the meter reads it correctly. Then after that hassle, just buy a Milwaukee MW102.

I’m using 88% lactic too. I’ve got the powdered test packets so I will double check the meter today. I’ve got some strips too, which I know are considered not trust worthy, but they always read low too. I am also having some efficiently problems too so I’ve got some things to figure out.

 

[VikeMan]

Does the Sodium Metabisulphite change ph?

Yes, it lowers pH. How much will depend on how much you use (obviously), but also on the buffering capacity of everything else in your mash. As a rule of thumb, some of the LODO brewers use this:
PH Drop = ( PPM Metabisulfite / 100 ) * 0.1

 

[DuncB]

You don't say when you are measuring the pH.
After adding the acid and sod met is not the time to test.
Wait a period of time into the mash I'm never sure exactly when this should be.
Cool the wort to 20C regardless of it saying it temp corrects.
You must also store the meter bulb end in storage medium, not test medium or water.
You are right to check the calibration, but also ensure this medium is all off before checking your sample.

 

[kurds_2408]

You don't say when you are measuring the pH.
After adding the acid and sod met is not the time to test.
Wait a period of time into the mash I'm never sure exactly when this should be.
Cool the wort to 20C regardless of it saying it temp corrects.
You must also store the meter bulb end in storage medium, not test medium or water.
You are right to check the calibration, but also ensure this medium is all off before checking your sample.

Yes, it lowers pH. How much will depend on how much you use (obviously), but also on the buffering capacity of everything else in your mash. As a rule of thumb, some of the LODO brewers use this:
PH Drop = ( PPM Metabisulfite / 100 ) * 0.1

I measure 10min into the mash. I’ve both cooled and not cooled. I am using like .1 grams of sodium metabisulfite depending on how much strike water I use. Brewfather doesn’t change whether I input that or not.

 

[DuncB]

I'd run with the predictions from brewfather and then see if you can either borrow another pH meter or test yours against theirs.

 

[micraftbeer]

Another idea came to me. Maybe the thing you're measuring your acid additions is off. Like maybe it's oz instead of ml. Or maybe it's grossly inaccurate and gives you more than your thinking.

 

[kurds_2408]

Another idea came to me. Maybe the thing you're measuring your acid additions is off. Like maybe it's oz instead of ml. Or maybe it's grossly inaccurate and gives you more than your thinking.

You know that had crossed my mind. I’m just using cheap o amazon pipette. I’ve got the day off today and planning to do several experiments with my equipment since I’m getting bad efficiency lately. Included will be ph meter calibration a now I’ll also check my pipette.

 

[kurds_2408]

Well I had the day free yesterday and spent a good 6 hours running all kinds of test on my equipment since I’ve also been having some efficiency issues. I did discover some things related to my ph issues that should help.
1. Brewfather had my lactic acid as 80% instead of 88%
2. My first couple recipes I entered before getting my water lab tested had starting ph 1 point high than my actual ph.
3. Yes my ph meter was out of calibration, .5-.75 low depending on the solution. I will be more diligent with calibrating it from now on.
4. While my pipette for acid was accurate it is very difficult to use correctly without air bubbles so I ordered a better way to measure.

I’ll be brewing a proven recipe in a few days to test everything and report back if my issues have been fixed.

 

[VikeMan]

2. My first couple recipes I entered before getting my water lab tested had starting ph 1 point high than my actual ph.

I don't know of any water models that use the base water's pH in their mash pH formulae. I assume Brewfather is the same. It shouldn't matter what pH you had entered. What matters are the ions from your water report.

 

[kurds_2408]

Oh ok. That‘s good to know.

 

[micraftbeer]

@kurds_2408 -appreciate the follow up on your findings. It seems like a lot of times, people don't post that.

As for your measurement vessel, I bought one of these awhile ago. It's worked great. I use a medicine syringe into my bottle of acid , then measure in this. What did you end up finding?

10ml Graduated Cylinder, Borosilicate 3.3 Glass, Single Metric Scale, Karter Scientific 213I10 (Single) https://a.co/d/a05aXPW

 

[kurds_2408]

@kurds_2408 -appreciate the follow up on your findings. It seems like a lot of times, people don't post that.

As for your measurement vessel, I bought one of these awhile ago. It's worked great. I use a medicine syringe into my bottle of acid , then measure in this. What did you end up finding?

10ml Graduated Cylinder, Borosilicate 3.3 Glass, Single Metric Scale, Karter Scientific 213I10 (Single) Amazon.com

Yeah definitely. I got a small graduated cylinder just like that. It gets delivered today. Gonna brew Sunday if the snow holds off and see if my problem are fixed.

 

[kurds_2408]

I’m in the middle of the brew right now and just thought I’d update. After all my tests and calibration the ph is now spot on. BF said it should be 5.59 and I was exactly 5.59. Thanks for all the help guys. Really glad I got it dialed in.