I feel like I asked BB about that but I don’t remember the answer. It does seem necessary to add the later addition of acid if the mash + boil pH is in the mid-5s. I do think there is a flavor benefit as well.
I have added 1/8 tsp of 10% phosphoric acid to 9 gal distilled water to create total brewhaus liquor in the ~5-5.5ish pH range. I strike and sparge with that. I have also left it out with zero issue whatsoever. Even if I do or don’t add the 1/8 tsp, after the mash is complete I do not add additional acid.
Some folks enjoy the technicalities of brewing. There are plenty of really thick technical books and lots of calculations to take them down that road. I am simply not one of them.
There are many ways to enjoy brewing beer at home. Not saying any other way is wrong. This is just the way I do it.
I’ve been homebrewing for a long time. It has become very rote for me. I love the end result, and I make good beer, but I have been on autopilot for a while. I need a new challenge.
pH is an aspect of the process I have historically not paid much attention to. It presents a new frontier for me. It’s not about “worrying” about it, it’s about having a new independent variable to play with and learn more about, which might help revive my flagging interest in the hobby.
BB’s IDGAF attitude resonated with me (BB, I know you GAF and your beers look awesome to me) so I did something similar by getting my water (source water, not RO or distilled) to a pH of 5.5 prior to heating it. That’s been working nicely. I have also withheld dark grains (in my case, midnight wheat) until the mash was done so that the darker grains did not futz with the pH. I probably won’t do that with most crystals but I would do it with MW and Carafa. I have also held onto some of the LO steps: Yeast + sugar top deox the water first, underletting my mash, using a mash cap, purging the keg with CO2 from the fermentation, doing a closed-transfer from fermenter-to-keg, etc. I have also been adding a late addition of acid with 10 minutes left in the boil. Believe it or not, that’s simplified. I cut out BTB altogether as well as the SMB + ascorbic acid. I take one pH reading now after the mash has sat for a bit and that’s just to confirm that the mash pH is where I expected it to be… which it always is because I start around 5.5 and do not add any dark grains to the mash. The mash pH is always 5.4 to maybe 5.55 at room temp.
Sounds like you have a good handle on your process, Ken. I also do the yeast oxygen scavenging process for zero o2 water from time to time and I feel that probably lowers the pH to a decent range although I’ve read it doesn’t have any meaningful impact on mash pH. It might be good for sparging though and you’d be sparging with already somewhat acidified water versus pH 7 or higher water.
I wanted to address this because earlier this year I had some beers that were stubborn to clear and there is a thread on that as well (clarity-specific). What I am trying to determine is whether a low mash pH or a low boil pH would result in clarity issues. I remember something on Kai’s site showing wort that was boiled at a pH of 5.5 and also 6.5. The higher one was darker and cloudier while the lower one looked clear and had the proper color. But I also seem to remember something about mashing or boiling at an improper pH that would create a permanent haze that you cannot get rid of and that sounds exactly like what I was experiencing. I would gel the beer in the keg and the haze would still be there. I would gel it again and the beer was still hazy. Whatever I have done with this ‘simplification’ routine seems to have fixed it. I also had meter issues so there were times when my meter would tell me that my mash pH was 5.17 or something at room temp. That’s in the 4s at mash temp. But that could also be my meter being wonky. Finally, BNW would suggest 4ml of acid be added to my strike water (based on my water, the grains used, etc) to get to a mash pH of about 5.4. But with me getting my strike water to 5.5 now prior to heating it, it only requires 2.75ml of acid. I did some thorough testing with two different meters that were both new (same brand… Apera) to make sure my 7.9 pH source water was getting to 5.5 and it took 2.75ml in those tests and each time I brew I add that amount to my strike water and then check my mash pH. So could adding 4ml of acid take my mash pH so low that some clarity issue was the result? I’m still scratching my head over that one.
Two possibilities: The alkalinity of the tap water differs from what you’ve entered in the software or the strength of the acid differs from what you’ve entered…or the software is wrong. I believe the software calculations are correct.
See? I knew that if I threw Martin under the bus he would post in this thread! 
Martin, I’m not sure. I could have misused the sheet. Very possible. My water has been pretty consistent ever since I started brewing all-grain in about 2004 and I have had 5-6 water analyses from Ward in that time. The bicarb has been right around 135-140ppm. I do remember talking with someone who was also having an issue with their version of BNW. He said that at some point no matter how much acid he added, he couldn’t get his target pH to drop below 5.5. He started adding absurd amounts. He mentioned it to me and I was able to get the sheet to do it for me as well except my figure was 5.4. But I know that many, many brewers use BNW and say that it’s always dead on so who knows?
All I can tell ya, Ken, is that it doesn’t do that for me.
I’ll be honest… I have never been super comfortable with it. It must just be the way my brain works or doesn’t work. I think I’ve actually asked other brewers if they would please enter in my information and tell me how much acid was required to get my mash pH to around 5.4 and they came back with “about 4ml”. So that part is odd. I can get my water to 5.5 with 2.75ml of 88% lactic acid so that’s my new approach.
Go with what works for you - Like Brew Bama said and Dave Taylor (kinda) said. I use the spreadsheets and don’t even bother testing pH anymore, since the results were so reliable back when I tested regularly. My RO is pretty blank slate though:
pH 6.4
Total Dissolved Solids (TDS) Est, ppm 26
Electrical Conductivity, mmho/cm 0.04
Cations / Anions, me/L 0.3 / 0.4
ppm
Sodium, Na 7
Potassium, K < 1
Calcium, Ca 0.4
Magnesium, Mg < 1
Total Hardness, CaCO3 < 1
Nitrate, NO3-N < 0.1 (SAFE)
Sulfate, SO4-S < 1
Chloride, Cl 1
Carbonate, CO3 < 1.0
Bicarbonate, HCO3 21
Total Alkalinity, CaCO3 17
Total Phosphorus, P < 0.01
Total Iron, Fe < 0.01
“<” - Not Detected / Below Detection Limit
And…I use acidulated malt as the main pH adjustment, together with some CaCl2 and CaSO4 to get the salts up a bit and for extra clarity - 1 g BTB in the mash and 1 g BTB at the tail end of boil and Whirlfloc (half tab 3 minutes after BTB boil addition). Admittedly, every once in a great while something goes amiss and my beer isn’t gin clear. As long as it tastes acceptable, I chalk it up to chance. FWIW, I rarely add any dry hops.
Cheers for having a great discussion in this thread!
The past two days I’ve brewed a kolsch and a marzen, targeting a mash pH of 5.6-5.7, as measured at room temp, which in principle puts me in the ballpark of 5.40 if measured at mash temp. I used tap water, which in my city is very soft: 7ppm Ca, 2ppm Mg, 5ppm Na, 2ppm SO4, 5ppm Cl, 28ppm HCO3.
The kolsch was 97% Weyermann pilsner and 3% Weyermann vienna. Estimated SRM of 2.7. The mash pH hit 5.67, without any salts added to the strike water. This is an extremely pale grist, and I was able to hit the optimal mash pH without any added calcium.
The marzen had a more kilned grain bill, and the no-salts mash came in at 5.45 (again, measured at room temp). I added a little baking soda to nudge it upward to 5.62.
I apparently will never have to add calcium to hit my target mash pH, even for the lightest grain bills in terms of SRM. I find this conclusion odd–hitting the ideal mash pH for what is practically an all-pils grain bill without any salts intervention–but I can’t argue with the numbers.
I definitely needed to, and did, acidify the sparge water some, and will need to more, as I came close ph 6 and gravity 1.010 on the last runnings.
Oh, and that line equation from Narziss was spot on for both brews.
I ordered the cheap, expendable pH meter recommended by dmtaylor. I will use it to measure mash pH at mash temp so that I can get a sense of the offset between that and room-temp pH.
Lastly, for the experts: by not adding any calcium salts to the mash, am I risking beerstone more than I otherwise would? I do add salts to the kettle, but obviously I’m bypassing any oxalate precipitation that would occur in the MT with added calcium.
Do you mean this equation?
pH_Knockout ~= 1.86336 + (0.62686 * pH_Pre-Boil)
If so, the source document stated that the data for their chart was from Narziss, but I’m the one who regressed the charted data and thereby folded it into the above equation.
Yes, that equation. My apologies, I didn’t read your earlier comment carefully enough about how it was derived. Tip o’ the hat to ya, Silver. I’ll be curious to see if the regression line holds in my own brewery once I do more brews and collect a lot more data points. Speaking of, just curious, how many data points were used to create the equation, and what was the r2? Cheers.
The details can all be found here.
To continue this thread and evolve it a bit more, I had an interesting thought on mash pH which in turn effects kettle pH.
Although I normally let things ride when measuring mash pH (RDWHAHB), my last two batches of IPA were a bit high when I measured them. The room temperature reading was 5.71, not bad but slightly outside the optimal range. I added 75% phosphoric acid to bring the pH back to around 5.6. Martin’s program calculates that I should be at 5.48 for measured mash pH. I am usually right on with what Bru’n Water predicts but have been that high with the last two batches. My water profile is a custom one that I worked up after a lot of experimentation and the beer always comes out tasting really good. If it didn’t I would be in my wife’s doghouse seeing is that it is her favorite beer. BTW, I use RO water and build my profile from there.
I originally used Briess two row Brewers Malt for my base malt but have switched to a local malster, West Branch, and now use their pale malt, grown locally in Ohio, for my base malt because I like the flavor it imparts to the beer. Although the protein level is higher than Briess (I don’t have the spec sheets for their malts and can try to get them from the malster and learned this from one of the local homebrewers that is a consistent award winner), I think the higher pH could be due to the year in which it was harvested rather than the protein level in the malt, since protein levels can effect the diastatic power of the malt. Briess almost always came in right around the predicted mash pH and last year’s crop of West Branch did roughly the same, so I am thinking it probably could be due to the crop year and the weather patterns in Ohio for the particular crop year. I have not been able to find any documentation to confirm this so it is just a hunch that I have.
Interesting. I seem to remember a story about how Rahr Pale Ale malt seems to bring the mash pH down by a couple fractions of a point. I thought I was seeing things but a number of other brewers mentioned the same thing.
In related news, I am making a pale Mexican lager this morning. I measured my mash pH and it clocked in at 5.56 (room temp) which should translate to somewhere between 5.31 and 5.36 depending on the offset you use. Strong’s offset would be 5.21. I’ll assume it’s squarely in the kill zone and move on. Cheers Beerheads.
I’d be happy with that as well. Good by anybody’s math.
Brewbama, what is this offset of which you speak? I was always under the impression that if you measure at room temperature, that is your mash pH. I apparently have missed an important point. Please enlighten me further
Goose - the offset is the measurement @ mash temperature (which varies if you step mash or decoct) vs pH at room temp (really 68 f for most meters). My garage in summer is never under 90 f - but I trust my device’s ATC and device chart offset for temp to determine my “room temp” mash pH.
It appears that actual real world deltas are smaller than the .25 -.30 offset in some printed and trusted resources.