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Acid/pH question

I brewed a 9-10 SRM beer yesterday. I have not had my water tested but having brewed plenty of times I know what I need to add for acid and gypsum to get where I think it needs to be. My question, is 4.5 tsp of phosphoric acid in the mash and then another 2 tsp in sparge water too much? I’ typically make darker beers than this so Ive never had to use that much acid. My mash pH at room temp was 5.25 and once all the wort was in the kettle, that pH was 5.4. This seems good to me, I just want to make sure I’m where I am supposed to be. And if this is getting to be too much acid.

What concentration phosphoric?

Unless you know what your tap water quality is, there is little advice that can be offered that would be valid. Programs like Bru’n Water can help out, but they are in a vacuum if there is no data on the water.

How have you figured out in the past that your acid and mineral additions were appropriate? Just the taste? That is OK to do and that is what ultimately matters…your happiness with the beer and taste.

Its hard to extrapolate that experience to other beers though. You would just have to continue with a trial and error approach with darker beers. It wouldn’t take too many brews to figure it out, but some brewers like to get their batches pretty close every time. They might fine tune their water a bit from there, but they want the water to not be the problem for their beer. That is where Bru’n Water comes in. It gets you close every time.

Spend a few dollars and get your water tested and then you can start figuring out what those water adjustments should be.

If your mash PH was measured at 5.25 at room temp, then the actual PH during the mash resides right around 5.0 PH due to the temp shift of .25-.3 at 150-160 etc… So you may be using just a touch too much acid as you want to measure 5.5>PH at room temp as your actual mash PH is then 5.2>

Edit* Say also its so much easier to use a pipette or graduated 10-20ml plastic dosage “syringe” for lack of better words and you can get them for free from pharmacies, you just have to ask. I have heard Fleet Farm carries them for farming needs or possibly the hardware store. Also are you aware of the prior posters water and mash PH software suite called brunwater? One of the features is It shows you how much ml of each acid you may need to reach a possible PH for mash and also has a tab to add a certain amount to sparge water. So with the measuring device and the free software your set once you know your waters possible mineral/ Bicarb content. BTW if you haven’t used it yet the website link is right in Martin’s signature above.

Just a two second hyjack but in the same subject if you will,
I want to say thank you also Martin as you can tell I am a big fan of the work you did to put it together also appreciate Kai’s time in this great work. I am finding still typically 0.10PH accuracy, have their been any recent updates or any substantial communications regarding Rahr 2 row or other? I have found something interesting I wonder if you have seen yet. If I insert a negative value into the SRM column such as -1.5 for Best Malz Pils 100% and then use 100% distilled I have a correct PH of say 5.7 and then I use the value of 0 for Rahr 2 row and the predicted PH is 5.6 Then if I add any color malts depending on brew with these two types and all my salts and acids such as used on tap supply during brew day the predicted PH is pretty much in agreement with actual.

The references given for ‘ideal’ mash pH ranges in the literature are of mash samples that have been cooled to room temperature. 5.25 is a touch on the low side, but still barely in the acceptable range. Shoot for 5.3-5.7
as measured at room temp.

Phosphoric acid doesn’t have a flavor so I don’t think it was too much if thats what it took to get your pH right.

I also check the finish pH of some commercial beers that I like and notice they are generally lower than mine that is why I have been shooting for lower mash pH. A typical beer for me that mashes at 5.5 pH will finish around 4.6-4.7 IME. Alot of the beers I like are around 4.2-4.3 so I am wondering if they mash low. I know there is a lot involved with how much the pH goes down during fermetation though. I am just experimenting with several batches of the same beer mashed at different pH.

The mashing PH and final beer PH are definitely oranges to apples subjects. You “could” in effect lower/raise final beer PH by affecting mash PH, sparge PH, wort calcium, FAN, yeast strain, CO2, the list goes on and on but its a gambling game way of doing it. Also how are you testing commercial beers completely out gassed or saturated with CO2? Irregardless final beer PH will always naturally stabilize to what is norm if your mash procedure falls within the widely held and known scientific knowledge such as mashes residing around 5.3-5.5 are the best of all worlds to maximize enzyme activity. Keeping final runnings under 6 etc…(most typically I mash around 5.3PH and see final runnings in the 5.6PH range due to correctly acidified sparging and my final PH is always right around 4.5 the biggest final PH diff I see is yeast related only EX: lager/ale)

Bottom line is moving far from norm to 5.0PH’s 0r 5.7PH’s will make less than the best beer possible. If you really have need to “experiment” with final beer PH the place to make the change is where you acidify the wort. IE: Make the most of mashing by following trusted values and add acid to the wort just before casting out to the fermentor if you feel your high or other and/or wait until fermented and acidify at this point. Which again naturally should never be a problem unless your doing some wacky stuff elsewhere.

Also analyzing your beer to commercial via finished PH is not a fair apples to apples comparison also as some brewers simply acidify bright wort, sterile filter and/or pasteurize for packaging and shelf life concerns which all have effects on final wort PH and/or stability of said PH. (IE: even though the beer taste and analysis is superb the lab says a drop from 4.5 to 4.3 will extend shelf life an extra 30 days etc…Because commercially PH at this point of the game is more about microbiological control more than beer flavors as these are all fully set by grist/minerals/mash PH/Mash temp/hops/yeast/yeast temp. So within 4.2-4.6PH the flavor doesn’t change much overall its all about shelf stability as beers will resist spoilage the closer to 4.0PH and will be susceptible to more spoilage organisms around 5.0. ) So unless you know the target breweries true SOP your never going to put an end to the guesses with these methods as you are inadvertently chasing a white rabbit and heading down unproductive aspects, where there is plenty other for home brewers to adjust first before final PH becomes a concern.

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