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Link between RO+minerals and loss of yeast character?

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A.J., for RO water of good quality (as measured by a simple TDS meter, if by no other means) it is certainly true that it may be treated as if it is distilled. But for RO water from sources who may not have checked their RO elements in some time, or for cases where the source water alkalinity is through the roof (as for example my own well water with 532 ppm bicarbonate) there can be alkalinity present which makes a difference with respect to the mash pH.

I'm always skeptical of supermarket or drugstore type RO machines where you bring in and fill your own jugs.
 
Why? I'm seeing the poor correlation now, but could you, Martin or AJ indicate some of why a more lightly colored malt might have more acidity? Is this about phosphate precip.?

More sugar, more reducing ends to get oxidized to -COOH?



Getting a touch of it, AJ. There's no need for acid either in the mash or the sparge if using RO or DI water. However, if using one's own water - say, highly carbonate, properly boiled water - you wouldn't know what's left but you could certainly bring it to proper pH for mashing, by making up a cistern totalling the mashing and sparging water - or, 20 gallons, whatever - and acidify it to 5.2-5.4. Is that correct?
Yes.


Trying to recall - deClerck's recommendation you mentioned, 3 samples. Is this what you're talking of here? I once owned his book(s), as well as Kunze's. I plan on getting both in the new year, as I miss what was in them.

I think you may be referring to DeClerk's recommendations for calculating lime additions. He gives a procedure for doing this and then recommends treating three samples with the calculated amount and also ±10% of the calculated amount. You then use the dose that gave the best decarbonation scaled to the full volume to be treated.
 
A.J., for RO water of good quality (as measured by a simple TDS meter, if by no other means) it is certainly true that it may be treated as if it is distilled. But for RO water from sources who may not have checked their RO elements in some time, or for cases where the source water alkalinity is through the roof (as for example my own well water with 532 ppm bicarbonate) there can be alkalinity present which makes a difference with respect to the mash pH.
Granted but water out of an RO machine with alkalinity of a mEq/L isn't really RO water. But that is not the point. The point is that you have nicely summed up the reasons why sticking numbers into a spreadsheet that models malt acid/base properties based on correlation with color, modeling water's acid base properties by a year old Ward Labs alkalinity report and using CaCl2 of questionable purity are unlikely to lead to an accurate pH estimate. I'm pointing out that there are ways to, even fairly simply, overcome most of these difficulties if one is willing to make a little effort, and come up with a pretty good estimate of mash pH or, perhaps more importantly, a good estimate of the amount of acid (or base) needed to hit a desired mash pH.
 
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More sugar, more reducing ends to get oxidized to -COOH?

I see. Thanks, AJ. I've been spending the last hour sort of following chains, much like you recommend: "when you come across something you don't understand, go off on a side investigation...." and it of course leads to a pretty wide sea-sojourn. So this is another one, this notion. Fascinating.


Thanks. I wonder if I could ask for what may be a bit of a subjective response? Needing acid, I know the virtues now of lactic, and phosphoric. I've got this bottle of 37% HCL that I'll dilute to 10% (or 1N, possibly?), wanting to play with British practice. If I could find food-grade sulfuric, I'd join them in a kind of made-up CRS. Is there any reason to believe not all sulfates or chlorides are the same? Salt or acid, we're doing the same thing (while strongly releasing H+ into solution with the acids)?

I think you may be referring to DeClerk's recommendations for calculating lime additions. He gives a procedure for doing this and then recommends treating three samples with the calculated amount and also ±10% of the calculated amount. You then use the dose that gave the best decarbonation scaled to the full volume to be treated.

Thanks, found it. Seeing your discussion with Silver on the potential low quality of store-bought RO (our local coop has a machine, but I've extremely little confidence now that they maintain it properly. Duuuude. Wanna mango? ya know....). And I've never lost the desire to at least try a more traditional approach to water treatment, whether it be boiling or lime. I've got the 10 pages up begun by Yooper, and am looking forward to trying it out. With Mg reported as 41 ppm, I do think I'll do a split regime, and learn what to do after, to measure what needs to be put back in. Thanks.

Basically, I think, the plan is to drop carbonate out, put needed ions back in, and adjust to mash pH of 5.2-5.4 with acid; storing all in a liquor tank, of sorts, for brew day. Is that reasonable?
 
Thanks. I wonder if I could ask for what may be a bit of a subjective response? Needing acid, I know the virtues now of lactic, and phosphoric. I've got this bottle of 37% HCL that I'll dilute to 10% (or 1N, possibly?), wanting to play with British practice. If I could find food-grade sulfuric, I'd join them in a kind of made-up CRS. Is there any reason to believe not all sulfates or chlorides are the same? Salt or acid, we're doing the same thing (while strongly releasing H+ into solution with the acids)?
Yes. A sulfate ion is a sulfate ion whether it came from calcium sulfate, uranium sulfate (do NOT use this in your beer - it is very poisonous) or sulfuric acid.

Basically, I think, the plan is to drop carbonate out, put needed ions back in, and adjust to mash pH of 5.2-5.4 with acid; storing all in a liquor tank, of sorts, for brew day. Is that reasonable?
Yes
 
Getting back to the main question.

It's about a week and a half since I brewed the tap water Belgian. I took a gravity reading a couple nights ago and made a few observations. Fruity aromas coming from the fermentor, but the small gravity sample I took smells and tastes neutral rather than estery or phenolic. That said, it's quite characterful in terms of malt profile, and there's a little something else hiding under that new beer greenness. I'll be testing again in a few days, after the beer has had a chance to clean up.
 
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Life got in the way of bringing this experiment to a timely conclusion, so I just got around to packaging this beer a few days ago. The jury is still out on whether tap water results in a more expressive yeast character than RO, as the beer tasted relatively neutral at bottling time in that regard. Another 4 - 8 weeks and I'll know if there is any difference from my previous RO batches.

I have since brewed again using a portion of tap water, and while I don't have an answer yet regarding yeast character, I have noticed a few striking differences between batches where I used 100% RO water + minerals and those that include a percentage of tap water. Keeping in mind these observations are based on a string of RO-based batches followed by just two tap water batches in a row... so by no means conclusive.

From my observations, the two tap water batches resulted in:
- Increased hot break activity. Aggressive foaming taking significantly more time to dissipate.
- Aggressive primary fermentation, with a surprising increase in krausen production.
- More rounded malt profile and fuller flavor post-fermentation.

I'll need to brew a few more batches to know if these differences could be a trend or if its just a fluke. If there is a trend, I'm wondering what it could be. Micro-nutrients have been mentioned. Also, could alkalinity play a role beyond buffering capacity?
 
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From my observations, the two tap water batches resulted in:
- Increased hot break activity. Aggressive foaming taking significantly more time to dissipate.
- Aggressive primary fermentation, with a surprising increase in krausen production.
- More rounded malt profile and fuller flavor post-fermentation.

Were the tap water batches brought to a similar mash pH as for the RO batch? pH does have an effect on protein degradation.

Alkalinity doesn't really have a role beyond buffering. Upon reaction with any acid, bicarbonate leaves the wort as CO2.
 
Yes but this buffering results in higher mash pH which, as you note, has an effect on protein lysis and many other mash reactions too.

Apparently the yeast performed with more vigor suggesting that perhaps the tap water contained some zinc whereas the RO didn't.
 
Maybe it does but many brewers add a bit and most yeast supplements contain some. That may only prove that the manufacturers know more about marketing than I do about brewing science.
 
I use RO and minerals as well as wyeast nutrient and I would say I tend to get very little esters even from known estery ale britsh ale yeast. I do get some fruity ester flavor from a few lager yeasts.

One of the Brew strong episodes they were discussing FAN and mentioned the FAN associated with esters is the last to be used. I wonder if adding nutrients might prevent the yeast from getting to the FAN that produces esters.
 
Nope. There is only a teeny need for zinc and the malt doesn't supply enough for the yeast. Many raw water supplies have sufficient zinc, but the RO process strips it out.


There are a few water profiles that are difficult to duplicate without magnesium chloride, but I'm not sure that I would really worry about trying to nail a profile.

Over the past few months, I've come to the conclusion that there is no reason to add Mg unless the brewer wants the flavor contributions of Mg. Wort supplies all the Mg the yeast need. I've previously stated that there are lab studies that prove that Mg is required as a trace element for good yeast health and flocculation performance. That test report used a sugar based fermentation medium and was purposely Mg deficient. Wort delivers plenty of Mg for yeast health and flocculation.

You can also find mag chloride at health food and supplement stores. Unfortunately, I can't vouch for its purity and ionic strength. Some vendors might adulterate the stuff.

Not trying to be a jerk, but what has changed your mind?

I brew a lot of lighter beers and try to keep the mineral additions to a minimum. Trying to increase Mg with Epsom salt and keeping every thing balanced can be challenging, so I thought maybe I could add magnesium chloride and magnesium sulfate and that was how I found that post. Lately I have been dropping the Epsom for that reason and seeing the comments that malt/wort bring the Mg that is required.
 
Were the tap water batches brought to a similar mash pH as for the RO batch? pH does have an effect on protein degradation.

Alkalinity doesn't really have a role beyond buffering. Upon reaction with any acid, bicarbonate leaves the wort as CO2.
Yes, I carefully monitored pH in both batches. The first was a Belgian Pale where I used 75% alkaline tap water. I was shooting for 5.36 but came in at 5.6. I added more acid to achieve 5.5, and then another small addition to knock it down a little more. The second batch was a Kölsch with 25% tap water top up, post-sparge. Similarly, it came in at 5.6, so I reduced it by ~0.15.
Yes but this buffering results in higher mash pH which, as you note, has an effect on protein lysis and many other mash reactions too.

Apparently the yeast performed with more vigor suggesting that perhaps the tap water contained some zinc whereas the RO didn't.
I used about 1/4 teaspoon of Wyeast brand nutrient. Closer to 1/2 tsp in my previous 100% RO batches.
 
I apologize, but I'm not following what you're getting at. Your citations go from zinc to magnesium. I believe I can still stand with both quotes.
I am the one that needs to apologize, sorry for the confusion. I wrote zinc but in my mind I was thinking magnesium for some reason.

edit: Still clear as mud I bet. Recall reading you did not need to worry about magnesium as a mineral addition as there is usually enough in malt. Seen zinc but confused that with magnesium, hence my original comment/post.
 
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Brew day.

Actual RT mash pH at 20 minutes was 5.6, or 0.14 higher than my 5.36 estimate. I added an extra 1.0 ml lactic acid which dropped it to ~5.55, followed by another 0.5 ml. I didn't take another reading as I'm in the ballpark. Consequently, I added another 1.5 ml acid to the sparge water (4.5 up from 3.0). More than I wanted to be adding, but hey ho there ya go.

Alkalinity has been climbing over the past week according to the daily water reports. Also due to higher gravity, I had to mash at 1.0 quart per gallon rather than my usual 1.35.

This has been a good thread. I used bottled RO water / minerals on my last brew I just installed an RO system of my own going forward. I appreciate everyone's experience.

One comment. You said you added extra Lactic Acid at 20 minutes. I went to a water seminar given my John Palmer a couple months back in Omaha. I was able to talk to him afterwards for a while. He said that if your PH isn't right initially, that there is nothing you can do which will make a difference in the mash fast enough to do any good. Anything that the PH affects happens in the first 15 minutes of conversion. He said to take good notes to fix it next time. Tim
 
Getting the PH right in the mash isn't only about conversion efficiency. It's about the finished beer flavor, as well. High PH will extract tannins, and will effect hop isomerization which could lead to harsh bittering. It will also have an effect on the finished beer pH and it's perception, too high could lead to a 'flabby' feel.
 
Getting the PH right in the mash isn't only about conversion efficiency. It's about the finished beer flavor, as well. High PH will extract tannins, and will effect hop isomerization which could lead to harsh bittering. It will also have an effect on the finished beer pH and it's perception, too high could lead to a 'flabby' feel.

I couldn't have said it any better!

With respect to Palmer's contention that if the pH isn't right initially, it can't be helped...I don't agree fully. While the first 15 minutes of the mash are important, it certainly takes more time for all the effects of the mash to occur. All hope is not lost, but as long as the mash pH is somewhere in the ballpark, I do agree with John's recommendation to take good notes and fix it next time.
 
This has been a good thread. I used bottled RO water / minerals on my last brew I just installed an RO system of my own going forward. I appreciate everyone's experience.

One comment. You said you added extra Lactic Acid at 20 minutes. I went to a water seminar given my John Palmer a couple months back in Omaha. I was able to talk to him afterwards for a while. He said that if your PH isn't right initially, that there is nothing you can do which will make a difference in the mash fast enough to do any good. Anything that the PH affects happens in the first 15 minutes of conversion. He said to take good notes to fix it next time. Tim

I agree with others about the flavor aspect of getting the mash pH right, even if I come in high initially. That first tap water batch I brewed, the Belgian with 75% TW, was a bugger to estimate because of my fluctuating river water and high alkalinity. Due to my fussing around, I may have overdone it a bit with the sparge acid additions. Turns out to be a happy accident though, because there's a pleasant snappiness to the beer. Certainly not acidic or sour, but just enough that its there.
 
That first tap water batch I brewed, the Belgian with 75% TW, was a bugger to estimate because of my fluctuating river water and high alkalinity.
Then let me pass along again the tip that handles this problem. Don't estimate. Just add acid until the water is at the desired mash pH. Estimate the required acid for the grains by telling your calculator/spreadsheet you are using water with 0 alkalinity. You, in effect, are. Make a test mash with the acidified water and adjust as necessary.
 
Then let me pass along again the tip that handles this problem. Don't estimate. Just add acid until the water is at the desired mash pH. Estimate the required acid for the grains by telling your calculator/spreadsheet you are using water with 0 alkalinity. You, in effect, are. Make a test mash with the acidified water and adjust as necessary.

Okay, thanks for the tip. Juts to be sure I'm following you correctly, are you saying I should get my mash water (say 3 gallons), treated so that it measures about ~5.3? Then, assume minerals stay the same but that alkalinity is 0, add grains and more acid as required?
 
19 Feb 2018 update

It's been about 6 weeks since I bottled the beer brewed with tap water and I think I can say a few things at this point.

1) The malt character is more pronounced than my previous 100% RO batches. If anything, my RO batches come across as being very lager-like, regardless of malt profile and yeast.

2) This tap water batch has Belgian esters. They are subtle at the 6 week mark, but most definitely present. I brewed a Kölsch a couple weeks after this batch, where I mashed and sparged with RO+minerals and topped up with about 1.5 gallons tap water to reach preboil volume. It's been kegged now for just over a week and has noticeable white wine yeast character that you expect from WY 2565. My previous Kölsch batches with RO were neutral.

3) I mentioned previously that I observed extended hot break with the tap water batches. I brewed again today and got the same results, so that's three tap water batches in a row with aggressive hot break.

There's one variable in all of this. I've been steadily reducing the amount of Wyeast nutrient I add, and I don't know if this impacts my results.
 
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It's been about 6 weeks since I bottled the beer brewed with tap water and I think I can say a few things at this point.

1) The malt character is more pronounced than my previous 100% RO batches. If anything, my RO batches come across as being very lager-like, regardless off malt profile and yeast.

2) This tap water batch has Belgian esters. They are subtle at the 6 week mark, but most definitely present. I brewed a Kölsch a couple weeks after this batch, where I mashed and sparged with RO+minerals and topped up with about 1.5 gallons tap water to reach preboil volume. It's been kegged now for just over a week and has noticeable white wine yeast character that you expect from WY 2565. My previous Kölsch batches with RO were neutral.

3) I mentioned previously that I observed extended hot break with the tap water batches. I brewed again today and got the same results, so that's three tap water batches in a row with aggressive hot break.

There's one variable in all of this. I've been steadily reducing the amount of Wyeast nutrient I add, and I don't know if this impacts my results.

An enlightening posting. Yeast nutrient improves the health of ailing yeast and speeds up fermentation and the reverse will be noticable in ways other than just taste, so if you have stressed the yeast to increase esters, at the same time there would be extra observable differences.

Enjoy those resulting beers.
 

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