Another stupid ph question

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B-Rad13

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So I can't seem to find the answer to this, when are you supposed to check your ph. In the water or in the mash. I know mashing raises the ph. I know I want to be at 5.2 for best results.
Thanks
 
Alkalinity is the buffering capacity of the water. The higher the alkalinity, the more acid you can introduce without changing the actual pH of the liquid.

So if there's a lot of alkalinity and the grist doesn't provide enough acid (roughly speaking, the darker the malt, the more acid it provides), the resulting pH of the mash can be too high for optimum results.

That's why additional acid is being introduced, mainly in pale grists, to counter this effect and to bring the mash pH into the desired area. Most brewing software can give you the right direction. An easy ballpark fix is 1-2% of the grist as acid malt. That's not very scientific, but it works.
 
Alkalinity is the buffering capacity of the water. The higher the alkalinity, the more acid you can introduce without changing the actual pH of the liquid.

So if there's a lot of alkalinity and the grist doesn't provide enough acid (roughly speaking, the darker the malt, the more acid it provides), the resulting pH of the mash can be too high for optimum results.

That's why additional acid is being introduced, mainly in pale grists, to counter this effect and to bring the mash pH into the desired area. Most brewing software can give you the right direction. An easy ballpark fix is 1-2% of the grist as acid malt. That's not very scientific, but it works.
Thank you, so I guess since I am on well water maybe I have higher alkalinity and that is why it's hard to bring my phone down?
Second part to my question you need the 5.2 for good conversion right, so when is the perfect time for adjustment?
 
Thank you, so I guess since I am on well water maybe I have higher alkalinity and that is why it's hard to bring my phone down?
Second part to my question you need the 5.2 for good conversion right, so when is the perfect time for adjustment?
Usually about 10 minutes into the mash is when to check and adjust as necessary
 
Thank you, so I guess since I am on well water maybe I have higher alkalinity and that is why it's hard to bring my phone down?
Second part to my question you need the 5.2 for good conversion right, so when is the perfect time for adjustment?
It depends on the water, ideally you would take a sample and run a lab test. They will figure out your ions and your alkalinity and then you will know for sure what is going on with your water. There are some labs in the US that do it for fairly little money but I do not know the companies, somebody else might chime in. I'm living in Germany.

Best Adjustment timing is when you collect your water and bring it up to doughing in temperature or directly before doughing in. Meaning, the acid should be present from the start. The mash pH will need some time to settle, any reading before about 15 minutes into the mash will be not correct. Unfortunately, 15 minutes into the mash, most of the conversion is already done and mash adjustments would come too late. So your mash pH meassurements wil provide information for your future brews, not for the current one. If you already know that you have relatively high alkalinity due to previous pH meassurements, it is pretty safe to say that for a normal strength beer around 1.05 OG with a pale grist like most of the lagers or pale ales, you could just add 2% of the grist as acid malt to the recipe and you will hit your desired range of mash pH. This is not going to be precisely acurate but it will bring you into the range that is good for conversion and mashing in general. I am using this method since years with multiple water sources and it never let me down. Nowadays I have relatively low alkalinity, so I am just using 0.5 to 1 % of the grist as acid malt addition. When brewing dark beers, I skip it entirely.

This knowledge comes with practice, you will get a feel for it.
 
It depends on the water, ideally you would take a sample and run a lab test. They will figure out your ions and your alkalinity and then you will know for sure what is going on with your water. There are some labs in the US that do it for fairly little money but I do not know the companies, somebody else might chime in. I'm living in Germany.

Best Adjustment timing is when you collect your water and bring it up to doughing in temperature or directly before doughing in. Meaning, the acid should be present from the start. The mash pH will need some time to settle, any reading before about 15 minutes into the mash will be not correct. Unfortunately, 15 minutes into the mash, most of the conversion is already done and mash adjustments would come too late. So your mash pH meassurements wil provide information for your future brews, not for the current one. If you already know that you have relatively high alkalinity due to previous pH meassurements, it is pretty safe to say that for a normal strength beer around 1.05 OG with a pale grist like most of the lagers or pale ales, you could just add 2% of the grist as acid malt to the recipe and you will hit your desired range of mash pH. This is not going to be precisely acurate but it will bring you into the range that is good for conversion and mashing in general. I am using this method since years with multiple water sources and it never let me down. Nowadays I have relatively low alkalinity, so I am just using 0.5 to 1 % of the grist as acid malt addition. When brewing dark beers, I skip it entirely.

This knowledge comes with practice, you will get a feel for it.
Thanks for the great explanation
 
So bottom line is you can either run a water test (Ward Labs has been around forever, not super expensive), or use trial and error to dial in successive batches.

Either way, keep good notes. With good notes and a few different beers, you may be able to back into approximate residual alkalinity without a lab test. Lab test would give you other useful information, though, like sodium, sulfate, and chloride levels.
 
So bottom line is you can either run a water test (Ward Labs has been around forever, not super expensive), or use trial and error to dial in successive batches.

Either way, keep good notes. With good notes and a few different beers, you may be able to back into approximate residual alkalinity without a lab test. Lab test would give you other useful information, though, like sodium, sulfate, and chloride levels.
Yep, that sums it up. I also would recommend a lab test, just because of the other ions that might be or might not be present.

The main things you want to look at is alkalinity, Ca, So4 and Cl. In that order. Sufficient Ca is necessary for yeast health and yeast flocculation (I'd aim for at least 100 ppm) and SO4 and Cl are basically factors that somehow can aid the flavour in it's own way. The last two are not that important. They can make a great beer a bit greater, but they will not turn a bad beer good or a mediocre beer great.
 
Since you have well water, a Ward Labs water test might be a good idea. If you had municipal water you could get their report. Knowing what's in your water would be helpful.

If your well water turns out to be high in minerals you can mix in some distilled or deionized water to reduce the levels.
 
Yes, I agree. Check your pH after the mash has had time to interact with the water (I do 30 min. in) and take note for the next similar grain bill brew. If your next beer is a stout and you were brewing a pils they will not be the same :)

Also, pH should be measured with a cooled sample. Meaning you take a little liquid out of your mash, cool it to 75F then take your reading. That is the number you should use to compare to targets.

Also also, while the homebrew world is stuck on pH 5.2, the famous brewing textbooks lean more towards a mash of pH 5.6 then adding acid towards the end of the boil to get down to a final of pH 5.1-5.3 pH 5.6 results in better extraction and limits SMM which reduces the amount of DMS and Whirfloc works better in the pH 5.1-5.3 range.

Yes, too much information but since you are new, I want to expose you to the PhD way, not the homebrew way! Just do it.
 
My tap water is 7.1. Just via buffering of the mash I'm close to ideal mash pH levels. US EPA suggests tap water range of 6.5 to 8.5 to keep it from being corrosive to metals in the pipes. So 8 is certainly within range, just not "most water".
Most water will have a PH around 8.
 
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Water pH doesn't matter. Water alkalinity usually matters...

Cheers!
Slightly misleading statement, both matter. "Alkalinity and pH are closely related and often measured together. pH is a measurement of the concentration of hydrogen ions or the acidity of water. Alkalinity is the ability of the water to neutralize or buffer changes in acidity." Alkalinity is _more_ important for water _quality_. Water with high alkalinity has a pH of 7 or higher (like mine), but water with high pH doesn't always have high alkalinity.

REF: https://waterquality.montana.edu/well-ed/interpreting_results/fs_alkalinity_ph_tds.html
 
Most water will have a PH around 8.
You have some hard water...
Err... may tap water is 7.1
"Most" is doing a lot of work there, one way or another. More importantly and as already noted, it doesn't matter. My local authority says that our water pH is between 7.5 and 7.7 with alkalinity ranging from 20 - 50 ppm. I've never checked the pH, but I have checked TDS and it matches what they claim (50 - 90 ppm).
 
Slightly misleading statement, both matter. "Alkalinity and pH are closely related and often measured together. pH is a measurement of the concentration of hydrogen ions or the acidity of water. Alkalinity is the ability of the water to neutralize or buffer changes in acidity." Alkalinity is _more_ important for water _quality_. Water with high alkalinity has a pH of 7 or higher (like mine), but water with high pH doesn't always have high alkalinity.

REF: https://waterquality.montana.edu/well-ed/interpreting_results/fs_alkalinity_ph_tds.html
I think what Day Tripper was referring to is - starting water pH does not matter when it comes to mash pH. An all grain mash has a lot of buffering power which simply overwhelms the water pH no matter where it starts.
 
This is a very easy rule of thumb that will make your beer better right now while you give yourself a chance to really understand what's going on behind the scenes.


Right. I usually add lactic acid to light beers such as pale ales, but I add baking soda to dark beers such as stouts and porters. How much to add depends on a lot of factors such as your target pH and how much the grain lowers the pH, but I think that video helps lay out the "easy rule of thumb" you mention.
 
^That^ need for some addition to bring the mash pH up when brewing porters and stouts and similar really dark beers (and incurring sodium as a result) is why many folks have taken to adding their blackened malts near the end of the mash duration, thus allowing an acceptable mash pH to happen for most of the mash without the need for pH-raising/sodium-incurring additions. This works because there isn't any "conversion" happening with 300+ SRM malts :D

Cheers!
 
^That^ need for some addition to bring the mash pH up when brewing porters and stouts and similar really dark beers (and incurring sodium as a result) is why many folks have taken to adding their blackened malts near the end of the mash duration, thus allowing an acceptable mash pH to happen for most of the mash without the need for pH-raising/sodium-incurring additions. This works because there isn't any "conversion" happening with 300+ SRM malts :D

Cheers!
True story, I've never aided in bringing pH up. The most acidic I ever got was with a RIS and it landed around 4.95 in the middle of the mash. American Stout more like 5.0. It's a risk reward thing in that I swear I can taste small amounts of baking soda but haven't had any issues on the more acidic side.

I'd venture most 99% of major pH related brewing flaws are due to alkaline water and pale beers. At least such that I felt leaving this out of the rule of thumb made it more valuably simple.
 
Per every ones suggestions I am ordering the wards brew water test kit. I am using an RO system,any words of wisdom doing this anything I should or shouldn't do?
 
If you're using RO, you really don't need a water test.
That! ^

Besides, a water test is merely a snapshot of your (well) water. Depending on its source(s) it could fluctuate quite a bit with the seasons and such.

Also, if you decide to get any water tested, don't order a "kit!" All they do is send you an empty bottle for the extra bucks you pay... o_O
Instead, you can directly send Ward Labs a (small) bottle with your water to be tested. Directions are on their site.
 
If you're using RO, you really don't need a water test.
That's what I was thinking. I used to have a reef tank (saltwater aquarium) and what we used for that was RODI which is reverse osmosis deonaized water to make saltwater and that was basically zero tds. But just RO I guess still has things in it. So by everything that I have read when you add grains it's supposed to lower your ph. But again on my last batch I started with 5.2 and after mashing in it was over 6. On another batch I kept adding lactic acid to lower ph and my beer ended up coming out sour. So I am kinda stumped
 
That! ^

Besides, a water test is merely a snapshot of your (well) water. Depending on its source(s) it could fluctuate quite a bit with the seasons and such.

Also, if you decide to get any water tested, don't order a "kit!" All they do is send you an empty bottle for the extra bucks you pay... o_O
Instead, you can directly send Ward Labs a (small) bottle with your water to be tested. Directions are on their site.
Oh thanks
 
That's what I was thinking. I used to have a reef tank (saltwater aquarium) and what we used for that was RODI which is reverse osmosis deonaized water to make saltwater and that was basically zero tds. But just RO I guess still has things in it. So by everything that I have read when you add grains it's supposed to lower your ph. But again on my last batch I started with 5.2 and after mashing in it was over 6. On another batch I kept adding lactic acid to lower ph and my beer ended up coming out sour. So I am kinda stumped

You CAN use the DI stage if you want to but RO alone gets your TDS down in single digits such that you can just assume it's all zeros.

The color of the grain makeup influences where you mash pH will end up. That's why the beer colors drive different "rules" in my video above. Screenshot below. Notice that only the darkest beers (made with dark malts) land in a pH that doesn't require exogenous acids.

IMPORTANT: IT doesn't matter what your water pH is before the grain is added. Don't measure it.

You probably added too much lactic acid because you were expecting it to change too quickly or maybe your meter is not accurate or calibrated carefully. Aside from that, I agree that 6.0pH is too high.

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IMPORTANT: IT doesn't matter what your water pH is before the grain is added. Don't measure it.

This can't be repeated often enough: It doesn't matter what your water pH is before the grain is added. Don't measure it.

It's all about the alkalinity of the starting water, as that plus the grain bill, and any acid or base additions, is what controls the pH of the mash.

Brew on :mug:
 
So...another pH related question. How long does it, or should it take for you to get an accurate reading?

I've recently thrown away my pH meter in frustration because it was inconsistent with how long it took regardless of the various temperatures I attempted readings at.

This most recent experience gave me a different reading immediately after calibration, even after replacing with a brand new probe. (Kegland pH meter for reference). As in, I replaced the probe, calibrated in 4 solution, rinsed it off with RO water, then turned it off. Turned it back on, placed it back into a small sample of fresh 4 solution and it settled at 4.8 after a minute or so.
 
This most recent experience gave me a different reading immediately after calibration, even after replacing with a brand new probe. (Kegland pH meter for reference). As in, I replaced the probe, calibrated in 4 solution, rinsed it off with RO water, then turned it off. Turned it back on, placed it back into a small sample of fresh 4 solution and it settled at 4.8 after a minute or so.
How do you store your probes? If you let them dry out or store them in plain water, it's going to affect their accuracy over time. There are probe stabilizing solutions meant for storage. The probes for my Apera meter have slip-on covers that I fill with 4M KCl stabilizing solution and I've never had a problem.
 
It usually takes around 15-20 minutes for the mash pH to stabilize. By that time, it's probably too late to make any corrections, as the conversion is mostly done at that point. But measuring pH is useful to determine if your calculations were on the right track.

I use Bru n' Water and have found that the measured, room temp pH is within about .05 of the predicted. Good enough for me.
 
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