Link between RO+minerals and loss of yeast character?

[rhys333]

In further research into loss of character, I was shocked to find that in some cases this trait has been associated with mash acidification. I quote (with bolding) and also link to a 1975 source document for this (where it is found on page 68).



***Note that despite this quote referencing wort acidification, the acidification was done at the mash stage (as can be seen in the associated 'Table XI').***

http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.1975.tb03663.x/pdf

The point that peaked my interest here being that strike water (mash) acidification is mentioned to improve lautering and stability, but no mention is made for improved flavor, while for at least two test cases specific mention is made of such acidifications detriments to flavor (in the form of 'emptiness' and 'astringency').

I can't speak to that research, but my batches are consistent regardless of whether I'm using acid or not. It's just the yeast esters and phenolics that are absent. Perhaps also less of a mineral roundness that someone else described above. I stick with moderate mineral content though and haven't really experimented above 100 ppm, so I'm not focusing on the last one for the time being.

 

[McKnuckle]

Is there any trend with these bland beers you folks are discussing in terms of fermenter geometry? I’ve done a few 2.5 gal batches recently in 5 gal corny kegs, and have noticed some diminished flavor. There are no other obvious flaws - efficiency, attenuation, clarity, freshness, all good. Just a lack of “pop” across several styles.

 

[Silver_Is_Money]

Is there any trend with these bland beers you folks are discussing in terms of fermenter geometry? I’ve done a few 2.5 gal batches recently in 5 gal corny kegs, and have noticed some diminished flavor. There are no other obvious flaws - efficiency, attenuation, clarity, freshness, all good. Just a lack of “pop” across several styles.

My fermenter is always filled to nearly the same level, with about 1.1 gallon of headspace. Are you beginning to speculate that too much fermenter headspace may diminish flavor?

 

[McKnuckle]

I'm beginning to speculate that the tall/narrow corny shape might have something to do with it. I wouldn't start with "too much" headspace as the factor, though, since I'm comparing the corny ferments with 2.5 gal done in a 5 gal carboy. I think the carboy has more headspace, actually, but the wort has more surface area and less depth in that container, so arguably it is exposed to more air - and I think that may be a good thing. I really don't have an explanation, just wondered if others here noticed any correlation with fermenter type/shape.

 

[ParanoidAndroid]

Is there any trend with these bland beers you folks are discussing in terms of fermenter geometry? I’ve done a few 2.5 gal batches recently in 5 gal corny kegs, and have noticed some diminished flavor. There are no other obvious flaws - efficiency, attenuation, clarity, freshness, all good. Just a lack of “pop” across several styles.

I'm switching to brewing 3.5 gal batches in 5 gallon kegs to further minimize oxygen exposure during transfers and just make it easier to transfer all together. I'll have to return later to give my impressions after the next brew.

I do know that, at least on a commercial scale, that fermenter geometry does make a difference. The tall/slender fermenters have a higher pressure at the bottom of the vessel than a shorter/wider vessel (assuming same volume). Yeast act differently at different pressures. Whether its a favorable difference depends on several factors such as yeast strain, OG, temp, etc. I wouldn't think this would transfer over to the homebrew scale since there's not enough volume to create such a huge pressure, but you never know.

Another thing is surface area. The taller keg has a smaller surface area than the carboy, which means less beer comes in contact with krausen and any gasses right above the beer (both O2 and CO2). Once the yeast drops, the bottom of the keg provides less contact with yeast and beer, so yeast "clean-up" might be reduced.

I know there was a Brulosphy experiment where a keg fermentor vs carboy comparison reached statistical significance, so might want to look for that one.

 

[rhys333]

FWIW - from the start, I have used a wide bucket-style fermentor with approx 1:1 proportion. I had yeast character before (with tap water) and no yeast character now (with RO + minerals).

 

[McKnuckle]

I know there was a Brulosphy experiment where a keg fermentor vs carboy comparison reached statistical significance, so might want to look for that one.

Yes, I did read that - thank you - and they preferred the carboy. But maddeningly, there was not even an attempt made to capture why, even if it was just anecdotal and subjective. One person in the comments even challenged Marshall on it and his response was that the actual reasons weren't interesting to him.

Let us know how you make do with the keg fermenting.

 

[rhys333]

I'll be doing the tap water brewing experiment this weekend. As per my original post, I observed that characterful yeast strains are almost completely neutral when I brew with RO water plus minerals. My goal will be to see if tap water allows the yeast to be more expressive. I'm using Trappist High Gravity yeast in a simple pale beer.

BELGIAN 6 gallons @ 1.060, 28 IBU
87% 2 Row
5% C40
5% Flaked barley
3% Melanoidin
Tradition @ 60 & 15
WY 3787 Trappist slurry

Due to high alkalinity I'm going with 75% tap and 25% RO. 7.3 gallons combined, dosed with 3.6g CaCl2 and lactic acid to target a mash pH of 5.36. Low aeration, under-pitching yeast, temps mid-60s ramping to mid-70s. I'm hoping to have results by this time next week.

 

[rhys333]

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.

 

[Silver_Is_Money]

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 quarts per gallon rather than my usual 1.35.

It will be interesting to see if the tap water brings with it some character that you have found lacking with RO water and minerals.

 

[Silver_Is_Money]

I wonder if a general lack of sodium ions when building water from RO may contribute to loss of character and mouthfeel. I'm going to begin adding some NaCl to my strike and sparge water to see what this brings along with it. I'll start with around 30 ppm sodium. Alternatively (or in addition), for darker brews that require their mash pH to be raised a bit, baking soda will add sodium.

How high can sodium safely go before being detectable, as in being noticeable as salty?

 

[mabrungard]

Typical findings indicate that the taste threshold for sodium is around 250 ppm. That's where it really starts to taste salty. However, there can be a particularly antagonistic combination when high sodium and sulfate are present. Then the sodium level would likely need to be well below the original threshold.

When we were preparing the Water book, John Palmer did some simple trials to assess sodium effects. Surprisingly, he found that sodium content could be elevated into the 100 ppm range with enhanced perception of sweetness and no perceptions of saltiness. There is no problem with the very modest sodium levels presented in the color-based water profiles in Bru'n Water. The same can be said when adding a dose of baking soda to mashing water for a dark beer brew. The 30 to 50 ppm sodium increase can typically found to be a positive flavor contribution.

While I don't advocate strongly for sodium additions, its not really detrimental to beer flavor at modest levels. With that said, I feel that modest is 70 ppm and less for sodium.

 

[Gadjobrinus]

Martin, how do you feel about the central question of this thread - the paucity of flavor, possibly, when building entirely up from RO?

 

[mabrungard]

I've tasted beers made with unadulterated RO or distilled water and can attest that they can be bland. The process and outcome can be technically flawless, but the lack of 'character' in the beers was apparent to me. However, the premise that properly-amended brewing liquor that started with RO or distilled water is going to produce inferior beer or less yeast character does not agree with my experience.

The only factor that I believe should be addressed when using RO or distilled, is including a yeast nutrient that includes zinc.

 

[Gadjobrinus]

Thank you Martin, very interesting. I don't know the nutritional requirement of zinc. I'm using 3:1 RO:my tap, as our water is so heavily carbonated. I imagine the zinc level is quite low, right?

 

[mabrungard]

Many natural waters have a trace of zinc that is suitable for yeast health. All that is needed is 0.1 to 0.2 ppm Zn for yeast health. If I recall correctly, that 1 gram zinc sulfate heptahydrate per 10 or 20 barrels, does produce that 0.1 to 0.2 ppm dose.

 

[Gadjobrinus]

OK, great, many thanks, Martin.

 

[rhys333]

Update, 3 days into primary fermentation.

I'm noticing a significant change in yeast behavior with the tap water batch. Lag phase was longer than usual and the krausen was initially quite low as of yesterday evening (2.5 days in). This morning I noticed pronounced fruity yeast aroma and mega yeast growth. When I say mega, I mean it completely filled all 6-7 inches of head space (2 gallons worth), oil-canned the lid to near bursting, and spewed out the airlock (hopefully the starsan did too). I brew 6 gallons in a wide 8 gallon fermentor and I have never had this happen before. I had no choice but to do a partial top-crop.

Part of this may be explained by using 3787 Belgian, brewing 1% abv higher than normal, and warm 78F temp. Still, last time I used it the krausen stayed below the lid. I should add that I used half the amount of WY brand yeast nutrient than I usually add, just 1/4 tsp in 6 gallons.

 

[Silver_Is_Money]

Wow!!! That's one whoppingly healthy looking ferment.

 

[rhys333]

Wow!!! That's one whoppingly healthy looking ferment.

In hindsight, I probably shouldn't have locked the lid back down before I left this morning. It looked to be tapering off though.

EDIT: I was wrong. Second cleanout required.

 

[Silver_Is_Money]

OK, my recently bottled (2 weeks ago) Bohemian Pilsner still needs more bottle conditioning time to bring up the carbonation, but I can report that from my early sampling it is malty and deliciously flavorful, despite my use of only RO water and added minerals. Absolutely no lack of character here. I went heavy on the chloride and light on the sulfate. And I used Avangard Pilsner malt, which I can report is very good. Single infusion, mashed at 151 degrees for 60 min. 146 degrees at the end of the mash. Matches the orange color of Pilsner Urquell to a tee.

10 lbs. Avangard Pilsner
1 lb. Briess Veinna
8 Oz. Weyermann Melanoidin
6 Oz. Weyermann Acidulated

~7.6 gallons boiled, and ~6.1 gallons to the fermenter. Rehydrated W-34/70 yeast.

Each 5 gallons of high quality RO water (only 6 to 8 TDS per 'Clearwater Systems') received:
2.1 g. CaCl2
0.65 g. CaSO4
0.8 g. NaCl

Hops:
1/2 Oz. Magnum, 60 min boil
1 Oz. Sterling, 15 min boil
1 oz. Saaz, 5 min boil.

OG = 1.053
FG = 1.010

 

[Gadjobrinus]

I'm messing with Bru'n water, Silver. With 90% RO and an "amber dry" for my strong bitter, I have no need for any acid additions, and am getting an estimated mash pH of 5.32. I presume your salt additions above were also it, right - no acid addition?

Looks good, would love to see a pilsner full.

 

[Silver_Is_Money]

I'm messing with Bru'n water, Silver. With 90% RO and an "amber dry" for my strong bitter, I have no need for any acid additions, and am getting an estimated mash pH of 5.32. I presume your salt additions above were also it, right - no acid addition?

Looks good, would love to see a pilsner full.

I added 6 Oz. of acidulated malt to the mash, which is the nominal acid equivalent of adding about 4.75 mL of 88% lactic acid to the strike water.

 

[Gadjobrinus]

OK, thanks. What was your mash pH?

Edit: Silver, I'm asking, because acidifying at the same rate - or less, by a bit, 8.2 ml over 10.3 gallons of 88% lactic, I'm getting an estimated mash pH of 4.91. I know my salts are higher so need to compare apples to apples - just wondering, if starting with pure or close to pure RO and the use of mineral salts - do we really need acids?

Edit 2: For 10.3 gallons 90% RO mash, I add 7.2 g gypsum, 1.2 g CaCl, 0.05 epsom, 0.05 table salt. 2.6 ml 10% HCL (though don't need it), yielding mash pH of 5.29 with my grist (strong bitter, small amount of chocolate, debittered black; moderate in C120, 77).

Program has me sparging with some acid, but it's not necessary.

Anyway, it occurred to me - when we use pure RO, and add in Ca salts - why would we need any acid contribution at all?

 

[Silver_Is_Money]

OK, thanks. What was your mash pH?

I didn't measure it.

 

[Gadjobrinus]

OK, thanks. I'm going to run with this setup, to try it. I'm matching fairly closely Martin's "amber dry" profile, the obtained mineral figures seem reasonable and the mash pH estimation lines up so eager to try it.

Interesting recollection...when I brewed those years ago on a well with heavily carbonate water - I didn't know any better. I just boiled, used salts in the mash and phosphoric in the sparge, measured with a pH meter, without knowing the math behind what I was doing ("1.5 ml per gallon...") and the beer came out really well. Something like the Primer, maybe...brew, sensory evaluation, brew....

 

[Silver_Is_Money]

Anyway, it occurred to me - when we use pure RO, and add in Ca salts - why would we need any acid contribution at all?

Because Pilsner malt is quite basic with respect to the mash target of pH 5.4. European Pilsner malts can often be found to be between 5.8 and 6.0 in DI_Mash pH. Avangard specifies a minimum DI_Mash pH (Congress mash) of 5.8 for their Pilsner malt.

 

[Gadjobrinus]

OK, sure, makes sense. I think I was thinking that your Vienna and Melanoidin would have brought it within range, but obviously not. Appreciate your sharing, Silver, useful stuff.

 

[Silver_Is_Money]

OK, sure, makes sense. I think I was thinking that your Vienna and Melanoidin would have brought it within range, but obviously not. Appreciate your sharing, Silver, useful stuff.

Only the Melanoidin is acidic with respect to pH 5.4. And there are only 8 Oz of it vs. 11 Lbs. of the more basic malts.

 

[Gadjobrinus]

Only the Melanoidin is acidic with respect to pH 5.4. And there are only 8 Oz of it vs. 11 Lbs. of the more basic malts.

More to learn, because again I'm correlating any color at all with a drop in pH (hence, Vienna, being just a touch darker, etc....). This itself is another world to learn - malts and mash acidity.

 

[Silver_Is_Money]

Data I have from Briess indicates that (at least sometimes) their Vienna base malt is slightly more basic than their 2-Row Brewers base malt.

 

[Gadjobrinus]

I'm puzzled as to why...?

 

[Silver_Is_Money]

I'm puzzled as to why...?

Malt color (L) correlates poorly to DI_Mash pH.

 

[Gadjobrinus]

Yes, sorry, working on that one now. Jettisoning the notion of SRM and pH effect will take some doing, I'm afraid! AJ has been kind enough to provide some material and I've been reading over the last few days. Popular wisdom says, with highly alkaline water, when making stouts, porters, etc., don't worry about acidification - the mash pH will fall in fine. My experience from those years ago, IIRC correctly (very possibly, "no"), comports with that notion, more or less. I recall acidifying the sparge with phosphorus and using salts to some extent in the mash, but not for any adjustment to pH. Is this simply wrong, from a scientific point of view?

 

[Silver_Is_Money]

Whether or not to acidify or add base to strike water all comes down to the amount of acid in the malts that comprise the grist overall vs. the alkalinity and calcium/magnesium in the strike water, and the target mash pH. Deep roasted malts are acidic, but not nearly to the extent that caramel/crystal malts are acidic (color for color). I'm looking over Briess data as I type this, and their 120L Caramel malt is more acidic than roughly half of their appreciably darker deep roasted malts.

Alkalinity in the sparge water on the other hand virtually always benefits from acidification.

 

[Silver_Is_Money]

Here's another oddity. Deep roasted grains that are not malted are not as acidic (color for color) as deep roasted grains that are malted. No software that I'm aware of has attempted to address this anomaly to date. Including my own.

 

[Gadjobrinus]

Thanks Silver. Many old assumptions, need to dive in. Appreciate your explanations very much.

 

[Silver_Is_Money]

All of this makes me chuckle when people endlessly claim that by simply entering their grist components Lovibond colors and assigning them to a few nominal (and insufficient) malt classes they can make mash pH software hit measured actual mash pH virtually on the nose every time. This sort of reasoning must always be met with a great degree of skepticism. And I'm not excluding my own software here. Just trying to be as honest as I can be. Faith in software technology and confirmation bias in pH measurement and its interpretation are powerful forces to overcome.

 

[Gadjobrinus]

In other words, modeling of whatever sort using color (and/or malt classes, as well), is undependable. I'm guessing, grab your meter, brew, and adjust?

 

[Silver_Is_Money]

In other words, modeling of whatever sort using color (and/or malt classes, as well), is undependable. I'm guessing, grab your meter, brew, and adjust?

Adjust the next (essentially recipe identical) batch you mash based upon data gleaned from actual mash pH measurements of the current batch.

This is not to say that such software (mine included) will be useless for all applications. Provided that the user can confidently enter data properly and accurately for all required inputs it is certainly in most cases (though not 100% all cases) better than nothing. If it turns a 5.7 or higher pH mash into a mash that lands somewhere within the ballpark of a 5.2 to 5.6 pH mash it is better than nothing. If it turns a 5.1 pH or lower mash into a ballpark 5.2 to 5.6 pH mash it is better than nothing. And if it guides you into the avoidance of astringency due to its compensating for the alkalinity in sparge water it is potentially doing even more good for you overall than it may be accomplishing in the mash. Plus they are good tools for determining your mineralizations ppm with respect to the pertinent flavor and pH impacting ions.