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Old 08-19-2013, 01:40 PM   #11
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Originally Posted by grv
...For example, using Sauermalz in the grist would involve an anticipatory assumption that my mash pH would be too high without it. As a newbie to water chemistry, I'd be afraid to include it and find that I guessed wrong, making the problem worse...
But didn't you already show (by your 5.8 reading) that you need to acidify your mash? Looks like you can confidently add 3% acid malt and tweak from there.


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Old 08-19-2013, 02:54 PM   #12
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Thanks - I did read the primer, and was pretty excited about it because it is simple. Then I continued to read the comments afterwards, and managed to get myself somewhat confused as people debated the finer points.
That thread has gotten somewhat out of hand but nevertheless it's probably of value to see what other people are thinking, the kinds of questions they ask and the answers to those questions. You can use the Primer to get you going and then consider some of the other aspects as you learn more and gain experience.

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Most strategies I am seeing people take seem to involve assumptions about what the pH will be instead of what the pH actually is. For example, using Sauermalz in the grist would involve an anticipatory assumption that my mash pH would be too high without it. As a newbie to water chemistry, I'd be afraid to include it and find that I guessed wrong, making the problem worse.
But you have a pH meter and so don't have to guess. Take a portion of your grist, add some of the water you intend to mash with (warmed to strike temp), let the mix sit for 15 minutes then withdraw and cool some of the liquid and measure its pH. That is going to pretty close to the pH you will realize in the actual mash. Make your sauermalz adjustment (or not) based on that.


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I suppose with RO as a known baseline, it's safe to make those assumptions. I was just looking for a way to make quick tweaks on the fly. Thanks for the suggestions!
That is the concept behind the Primer but you are one step beyond it as you can measure pH. A wise thing to do.


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Old 08-19-2013, 03:04 PM   #13
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Maybe it's just my chicago water, but I never find a need to raise mash pH. Even brewing a big dark stout with 15% roasted/toasted/crystal only gets my pH down to 5.6. So don't worry about it until you know you have an issue.
I don't either and my water is pretty nominal.

Mash pH prediction is conceptually quite simple though most of the spreadsheets do not model malt acidity/alkalinity adequately. To begin with I believe most of them assume that the buffering capacity of malt is constant over a range of pH (which it isn't) and that it depends on malt color (which, of course, it does to some extent). For them to be more accurate they would have to expand their models to include the non-linearity but more significantly it would take hoards of co-ops or graduate students to get the data to put into those models as the process of completely characterizing a single lot of malt requires a lot of time consuming measurements.

If you use a spreadsheet or calculator and it tells you that you need to add alkali to a stout, don't take that at face value. Do a test mash as described in my previous post and make your decision based on that.

There are those who will tell you that a stout brewed at normal mash pH will be thin, sour and taste like a classic dry Irish stout drawing the conclusion that stouts should be mashed at higher than normal pH and that some alkali should be added for this reason. Now we are talking taste/personal preference. If you like stouts made at higher pH, then add the alkali. If you don't, don't.
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Old 08-19-2013, 04:01 PM   #14
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But you have a pH meter and so don't have to guess. Take a portion of your grist, add some of the water you intend to mash with (warmed to strike temp), let the mix sit for 15 minutes then withdraw and cool some of the liquid and measure its pH. That is going to pretty close to the pH you will realize in the actual mash. Make your sauermalz adjustment (or not) based on that.
Ok cool, so I can add it once the mash has begun. Because it's grain, I wasn't sure about how long it would take to have an impact, or whether it would skew things in ways I don't want. For example, I'd probably substitute the percentage instated of adding it if I knew beforehand that I'd need it.

Practically speaking, where other things remain constant, I can probably proactively adjust when brewing something for a second time in order to reduce the monkeying around at mash time, and take the reactive approach we've been talking about when brewing a recipe for the first time.

Thanks again, all!
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Old 08-19-2013, 04:47 PM   #15
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Ok cool, so I can add it once the mash has begun. ...
NO! He's not saying that. The idea is to do a 1-lb mini-mash and measure the pH. Then do your full mash using an amount of acid malt you need based on what you learned from your mini-mash.

Here's an example: last week I took 1 lb of my milled grains, added 3% acid malt (yes, 0.03 lb), did a mash in a small cooler. The pH after 20 minutes was 5.5, so I decided to adjust my recipe for the full batch to use 4% acid malt. Then I mashed the full batch starting with 4% acid malt. pH was 5.4, as expected. You can toss the mini-mash into your main batch if desired.
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Old 08-19-2013, 04:58 PM   #16
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Originally Posted by SpeedYellow
NO! He's not saying that. The idea is to do a 1-lb mini-mash and measure the pH. Then do your full mash using an amount of acid malt you need based on what you learned from your mini-mash.

Here's an example: last week I took 1 lb of my milled grains, added 3% acid malt (yes, 0.03 lb), did a mash in a small cooler. The pH after 20 minutes was 5.5, so I decided to adjust my recipe for the full batch to use 4% acid malt. Then I mashed the full batch starting with 4% acid malt. pH was 5.4, as expected. You can toss the mini-mash into your main batch if desired.
Oops! Ok, I get it now. Perhaps to keep things relatively simple, on my first brew of a recipe I will adjust the mash at mash time using pH meter and lactic acid, which can be done on the fly. Later on, if i brew the recipe again, I will substitute some percentage of the base for Sauermalz based on my data from the first time, checking pH to make sure I am on target. I'm crazy busy - just trying to find a way to have an improved process without mini mashes, etc. Thanks for the clarification.
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Old 08-19-2013, 05:58 PM   #17
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Originally Posted by SpeedYellow View Post
NO! He's not saying that. The idea is to do a 1-lb mini-mash and measure the pH. Then do your full mash using an amount of acid malt you need based on what you learned from your mini-mash.

Here's an example: last week I took 1 lb of my milled grains, added 3% acid malt (yes, 0.03 lb), did a mash in a small cooler. The pH after 20 minutes was 5.5, so I decided to adjust my recipe for the full batch to use 4% acid malt. Then I mashed the full batch starting with 4% acid malt. pH was 5.4, as expected. You can toss the mini-mash into your main batch if desired.
Mini mashes can be very small, I recommend 100g of grain in a mason jar of your brewing water in the ballpark of your mash temperature. This works out well becaues your grain bill % = the amount in grams needed for the 100g mash. The results are quick and give accurate information for brewing that same grainbill for your desired pH.
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Old 08-19-2013, 07:08 PM   #18
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Mini mashes can be very small, I recommend 100g of grain in a mason jar of your brewing water in the ballpark of your mash temperature. This works out well becaues your grain bill % = the amount in grams needed for the 100g mash. The results are quick and give accurate information for brewing that same grainbill for your desired pH.
Actually I like that idea. The only downside is that including the acid malt into the mini-mash probably isn't wise, since it would be really hard to measure such a small amount (or if it's already mixed into the milled grain, it would be hard to mix it up enough to get a good sample).

The upside is that it's easy to toss the jar into the microwave to warm it up as needed before dumping into the main mash.
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Old 08-19-2013, 09:20 PM   #19
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Actually I like that idea. The only downside is that including the acid malt into the mini-mash probably isn't wise, since it would be really hard to measure such a small amount (or if it's already mixed into the milled grain, it would be hard to mix it up enough to get a good sample).

The upside is that it's easy to toss the jar into the microwave to warm it up as needed before dumping into the main mash.
I skip the acid malt in the mini mashes and the .1 pH per 1% of the mash rule of thumb works out well. In one case I proved its 0.08 pH per 1% of the mash by incrementally adding acid malt. It's always good to do the mini mashes with your actual brewing water because it's easier to correlate the final acid adjustment.

I use the microwave for this too, and for heating gelatin [Edited, for when clearing beer].

Repeat beers & small recipe variations have played-out very well where no mini-mashes/mash adjustments were needed based on good information the first time brewing it.
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Old 08-19-2013, 11:34 PM   #20
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Originally Posted by DSmith

I skip the acid malt in the mini mashes and the .1 pH per 1% of the mash rule of thumb works out well. In one case I proved its 0.08 pH per 1% of the mash by incrementally adding acid malt. It's always good to do the mini mashes with your actual brewing water because it's easier to correlate the final acid adjustment.

I use the microwave for this too, and gelatin.

Repeat beers & small recipe variations have played-out very well where no mini-mashes/mash adjustments were needed based on good information the first time brewing it.
Why the gelatin in the mini mash? How are you guys making sure that the mini mash has the same % of each grain as the full scale mash? Do you mix the grains after milling to make sure they're not stratified, or scale down and measure each one (1 gram of this, 5 grams of that, etc.)?


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