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Using phosphoric acid to control mash Ph

I want to hit a ph of about 5.1 in room temp water, is that about right? or is it 5.5. Does Ph go up or down as water heats?

pH goes down as you heat the water.

So, if you’re using Bru’n water to target a pH for your water, and it tells you how much acid to add, how do you factor in the pH change when you heat the water? I read somewhere that you add the acid to cold water, then heat. But then you’re getting further pH drop as you heat.

Should you shoot for an acid addition that leaves your pH slightly higher than your target to account for the futher pH drop you’ll get when you heat the water?

I hope I’m asking this question clearly.

So, if you’re using Bru’n water to target a pH for your water, and it tells you how much acid to add, how do you factor in the pH change when you heat the water? I read somewhere that you add the acid to cold water, then heat. But then you’re getting further pH drop as you heat.

Should you shoot for an acid addition that leaves your pH slightly higher than your target to account for the futher pH drop you’ll get when you heat the water?

I hope I’m asking this question clearly.[/quote]

The phenomena of pH dropping when you heat water is a product of the water’s alkalinity (aka: temporary hardness). Heating drives off CO2 that was associated with the bicarbonate that produces that alkalinity. When you acidify water, you are chemically neutralizing the alkalinity and there is much less alkalinity and bicarbonate left in the water that can then be converted to CO2. Thus, there is not much change in pH or alkalinity upon heating when you’ve already acidified.

Yes, add acid to cold water. I think you might be overthinking this (or I haven’t had enough coffee yet :smiley: ) pH MEASUREMENTS change when taken at different temperatures. Take a pH measurement at room temp and heat it to 150F and then cool it back down to room temp and it will be the same as before.

Hmm, this is interesting. I have been focusing on this quite a lot lately and my process goes like this: I have my grains and my water additions (CaCl, gypsum, etc) in my MT and I add my 160°-ish water, stir, wait a few minutes and then grab a small sample and put it into a frozen glass and wait for it to get down to about 70-80° and then I place my meter in there and wait for it to stabilize. If it’s higher than I want (it’s always higher, never lower) then I add lactic acid directly to the MT, stir it again, wait a few minutes, stir again, take another sample, let it cool and check it again. Repeat until I’m in the 5.2 - 5.4 range. Anyone see an issue with the way I’m attacking this? My beers have been improving in multiple areas as I have spent more time on this. I also make sure that my [batch] sparge pH doesn’t get to 6.0 and also make sure that when all of the runnings have been collected, the pH of that is in the mid 5s. Thoughts?

Seems fine to me and resembles what I used to do before the advent of the water spreadsheets. Now I just use bru’n water. Since your brews are mostly lagers I think the mash range 5.2-5.4 is good for them but is a bit low for ales IMO. Typically when I see this range I think that it is intended for mash temps which translates roughly to 5.5-5.8 room temp.

I have been a little fuzzy on the temp part of things from day 1. I used to use the ColorpHast strips and some people would say to just dip the strip into the hot mash while others said to cool the sample first and THEN take the reading while still others mention the 0.3 correction factor that is built into the strip at warm temps which suggests that the temp of the sample doesn’t matter. Similarly, the meters have ATC (automatic temp correction) so my thinking was that the temp of the sample didn’t matter. I cool the sample so that I’m not putting my pH probe into 150° liquid but if the sample is 90° and the reading is 5.3, the temp continues to drop (my meter has a temp display on it) but the reading is still the same and I guess I thought it was the ATC doing that so you didn’t have to worry about the temp of the sample. Again, my beers have been improving as I have been wringing my hands over this so my guess is that I’m not as fuzzy as I thought… but if anyone has any additional light to shine into any dark corners I may have just posted about, please unfuzz me. I would hate to think I was doing this properly when there was something I was not clear about. Cheers Beerheads.

I think your process is fine. The confusion that exists is what temperature is the recommend pH value if a temperature is not stated? IE: Is it 5.2 at room temp (4.9 mash temp) or 5.2 mash temp (5.5 room temp) German brewing literature prefers lower pH values since lager yeasts do not drop pH much (why your beers are improving IMO). There are references suggesting 5.2 room temp (4.9 mash temp) but even Kai doesn’t go that low with his own recipes. I am pushing the envelope in the other direction trying ales at higher pH and think 5.5-5.8 room temp (5.2-5.5 mash temp) might be the way to go. It should be noted that any beer made within the ranges above should be pretty dang good…

I think you are on the right path for lager brewing pushing pH’s lower. I might go as far as to recommend you match the mash pH with your sparge water to drive the preboil toward 5.3-5.4 if you like what you are achieving and want try going even lower.

Nope. Water pH doesn’t really matter. It’s mash pH you need to be concerned with.

[quote=“zwiller”]I think your process is fine. The confusion that exists is what temperature is the recommend pH value if a temperature is not stated? IE: Is it 5.2 at room temp (4.9 mash temp) or 5.2 mash temp (5.5 room temp) German brewing literature prefers lower pH values since lager yeasts do not drop pH much (why your beers are improving IMO). There are references suggesting 5.2 room temp (4.9 mash temp) but even Kai doesn’t go that low with his own recipes. I am pushing the envelope in the other direction trying ales at higher pH and think 5.5-5.8 room temp (5.2-5.5 mash temp) might be the way to go. It should be noted that any beer made within the ranges above should be pretty dang good…

I think you are on the right path for lager brewing pushing pH’s lower. I might go as far as to recommend you match the mash pH with your sparge water to drive the preboil toward 5.3-5.4 if you like what you are achieving and want try going even lower.[/quote]
Yeah, I think we’re on the same page. There was something on Kai’s site (the pH page) where he showed two worts that were boiled for 10 minutes. One was at pH 5.5 and it was gold, clear and light. The other was at pH 6.5 and was grayish, cloudy and dark. I do make the occasional gold beer and I have seen that grayish color in my own beers so that’s where I decided to keep the preboil wort in the mid 5s. Some of this goes back to some conversations we have had about ‘flabby’ beers which apparently are made with higher mash and/or preboil wort pH and lack that snap beer drinkers look for. If the pH is too high, the resulting beer can be dull, boring, bland, etc. Apparently “flabby” = dull, boring, bland. :expressionless:

Nope. Water pH doesn’t really matter. It’s mash pH you need to be concerned with.[/quote]
This, I never quite understood. Wouldn’t a high (or low) water pH affect the mash pH?

Agreed Beersk…
can someone please walk me thru their process?
do I treat my mash to adjust ph? I know that depending on the grains, my ph will change, so WHEN is the best time to make my adjustments?
Adjusting my strike water? mash? Sparge? all 3?
Any help would be appreciated!
Cheers!

Beersk: I think that people say the pH of the water doesn’t matter because you’re not really worried about the pH until everything is mixed together. Plus, the pH of your water may or may not be an issue based on a number of things… the bicarb (which is very pesky and can cause high mash pH), what your grain bill is composed of, etc. Many water sources have a pH between 6.5 or so and maybe 9. If your water pH is 9 and your grain bill is full of dark malts, your water pH is not critical. More…

Gr8Abe: I think I mentioned my process earlier in the thread but here is a more detailed version: I admit that I use EZ_Water now to determine water additions, etc. Sorry to Martin but I just prefer it and I’m able to use it efficiently and simply. I have low calcium (34ppm) so I always use some combination of gypsum and CaCl to get calcium higher (50-60ppm) and to lower pH. When I have all of that on paper and it looks like my pH should be good, I proceed. I mix my 160°ish water (which may contain some percentage of distilled water to lower my 138ppm of bicarb) with my grains and salt additions. The temp usually settles around 154-155 which I do on purpose temporarily. I don’t have a direct-fired MT so I have to overshoot my mash temp while I get the pH right. I stir and let it sit for a few minutes and then I take a sample and put it into a frozen glass so I can get the temp down. When it’s 70° or 80°, I put my meter in there. If it’s anywhere between 5.2 and 5.4, I usually leave it. If it’s high, I add some lactic acid with a dropper. Usually anywhere from ½ml to 1ml to start. Stir, wait, check it again. All this time, my mash temp is slowly lowering. If the mash pH is still high, repeat. If it’s good, I concentrate on getting my mash temp right (keep stirring, add ice, whatever) and I stop. When I mix my sparge water for my batch sparge with the grains, I check the pH again to make sure that it doesn’t reach 6.0. 6.0 is supposedly the point when tannins can create harsh flavors in the beer. That water was mixed with the grains after the first runnings were drained and I typically do not add salts to the sparge and I have occasionally been close to 6.0 for the sparge so more acid is added just to keep it under 6.0. Then I recirc, drain and check the pH of all of the runnings before I boil. I lke to keep that around 5.5 based on the comments I made in another post regarding Kai’s pH page. Some people treat all of the water with salts beforehand. That might eliminate the higher sparge pH but I really just want to add salts to the mash. There are a lot of ways to do these things. When my mash pH is high, I could add more CaCl or gypsum to lower the mash pH instead of acid. But then you’re playing with the overall flavor or perception of flavor in the beer where the acid should work better and also be below the flavor threshold. I have been brewing for 15 years now and I have ruined many, many batches with experimentation. It’s only been in the last year or so where I have hit some grand slams by looking closely at water and these pH steps.

The best way is to have a good idea of what water and mineral adjustments will be needed before you even start. Then you just carry through with those adjustments and if you are really curious and have the equipment…then test the mash pH.

Not having an idea of what adjustments you need to make beforehand will often have you chasing your tail and possibly overshooting your target. The science is still a teeny bit fuzzy, but we have enough of a handle on it that we can use software like Bru’n Water to figure out those additions first.

Nope. Water pH doesn’t really matter. It’s mash pH you need to be concerned with.[/quote]
This, I never quite understood. Wouldn’t a high (or low) water pH affect the mash pH?[/quote]

Yes, but the grains in the mash will also affect the pH. So water is only one part of a synergistic puzzle. No matter what your water pH is, it will change when you add the grain. So, in that way, it’s the mash pH you need to be concerned about.

awesome response Ken! Thanks!
So there’s no issue with adding acid/ salts/ whatever directly to the mash?

Gr@abe,
Before I forget, 5.1 room temp is really low, man. Nearly all literature suggests to not go lower than 5.2. Might be too much of a good thing :smiley:

[quote=“Gr8abe”]awesome response Ken! Thanks!
So there’s no issue with adding acid/ salts/ whatever directly to the mash?[/quote]
You just have to understand what they’re doing for you and what impact they will have on the mash. For me, I want the mash pH correct and you have various tools for that. Acid will lower the mash pH and should not lend flavor unless you use quite a bit of it. Calcium chloride and gypsum will also lower mash pH but they have a flavor component too. Chlorides create a smoother, rounder, fuller character in the beer while sulfates (gypsum = calcium sulfate) create a crisper, edgier character. I’m almost always adding both to my mash and the ratio depends on the style of beer I’m making. There is calcium carbonate and baking soda which will raise pH (baking soda apparently being the preferred option). You can also add these to the boil which some people compare to adding salt to your food after it’s been prepared. But I try to focus on the mash and add everything there, then check the pH of the sparge (the sparge water and grains that have been mixed) to make sure the pH doesn’t approach 6.0 and then I look at the preboil wort and try to get it into the mid 5s. To start playing with the mash and what you will add to it, you need to know your water numbers and you need to know how the water might be tailored for the beer you’re making. It’s taken me awhile to get comfortable with this and I do not pretend to be an expert by any stretch (we have Denny, Martin and many others here who can fill that role) but I have gotten to the point where I know my system, my tastebuds and what I want to do for various styles. It’s only taken me 15 years. :expressionless:

EDIT: Also know that darker grains naturally lower pH. If I have a darker grain bill, I will probably be using less calcium chloride and/or gypsum because reaching my target mash pH will come a little easier. OTOH, making something more pale like a helles, kolsch, pils, American wheat, blonde ale, etc. might require more effort and in those cases I will use a little distilled water to get me to my mash pH easier. Using the distilled water will lower my bicarbonate which can keep the mash pH high.

I use slaked (pickling) lime to raise my pH for my dark beers rather than calcium carbonate or baking soda. I doesn’t take nearly as much as chalk and doesn’t make the beer taste “chalky”.

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