Link between RO+minerals and loss of yeast character?

[ParanoidAndroid]

My latest batch that used 80/20 RO/Tap blend turned out great. It was a Marzen malt/hop bill with a kolsch yeast. While the kolsch yeast isn't one that I would consider "estery" since I was shooting for a clean lager like brew, the carbonic bite was present and was overall way more flavorful and less bland than my past few brews which were at most 90/10 and usually less than that.

Try cutting the RO with some Tap. 80/20 apparently worked for me on the last one. I'll try a 75/25 next and probably just stay there from here on out.

 

[Buckeye_Hydro]

Remember that if you want dechlorinated tap water, your RO system makes that - use the water in the tube that feeds the RO membrane housing cap - that water has been through the sediment filter and the carbon block. Keep dechlorinated water flows out of that tube to less than about 0.5 gpm with a needle valve or even a little ball valve. Max service flow out of a 10" x 2.5" carbon block is usually 1 gpm, but going with a slower flow will allow for more complete treatment of the chlorine.

Russ

 

[rhys333]

My latest batch that used 80/20 RO/Tap blend turned out great. It was a Marzen malt/hop bill with a kolsch yeast. While the kolsch yeast isn't one that I would consider "estery" since I was shooting for a clean lager like brew, the carbonic bite was present and was overall way more flavorful and less bland than my past few brews which were at most 90/10 and usually less than that.

Try cutting the RO with some Tap. 80/20 apparently worked for me on the last one. I'll try a 75/25 next and probably just stay there from here on out.

I'm might go 50/50 on my next one. I was going to go 100% tap water, but the alkalinity is quite high.

 

[ParanoidAndroid]

I'm might go 50/50 on my next one. I was going to go 100% tap water, but the alkalinity is quite high.

That's the exact reason I went 100% RO. RA was sky high. Chased that off flavor for months. Something they fail to mention in Homebrewing 101.

 

[user 246304]

Remember that if you want dechlorinated tap water, your RO system makes that - use the water in the tube that feeds the RO membrane housing cap - that water has been through the sediment filter and the carbon block. Keep dechlorinated water flows out of that tube to less than about 0.5 gpm with a needle valve or even a little ball valve. Max service flow out of a 10" x 2.5" carbon block is usually 1 gpm, but going with a slower flow will allow for more complete treatment of the chlorine.

Russ

Russ, I know zero, we'll remember. But if wanting it for your brewing water, couldn't you just get your RO water and leave it out uncovered overnight?

 

[Buckeye_Hydro]

Because TFC membranes can't withstand chlorine exposure, the prefilters remove chlorine before it gets to the membrane... so, RO water should contain no chlorine.

 

[user 246304]

OK, thanks, Buckeye, perfect.

 

[rhys333]

That's the exact reason I went 100% RO. RA was sky high. Chased that off flavor for months. Something they fail to mention in Homebrewing 101.

My alkalinity is at 117mg CaCO3/L (142 ppm, if I have that conversion right). It takes a few mls of lactic acid on a dark brew to get it in range, so 50/50 or even 70/30 tap to RO should be about right depending on the SRM. I really should wait a few weeks, but I'm intrigued by the possibilities of this now and I might brew a Belgian this weekend. I should have an answer to my main question by the following weekend.

 

[ParanoidAndroid]

My alkalinity is at 117mg CaCO3/L (142 ppm, if I have that conversion right). It takes a few mls of lactic acid on a dark brew to get it in range, so 50/50 or even 70/30 tap to RO should be about right depending on the SRM. I really should wait a few weeks, but I'm intrigued by the possibilities of this now and I might brew a Belgian this weekend. I should have an answer to my main question by the following weekend.

My alkalinity was 227 ppm as CaCO3 when I got my test done about 3-4 years ago.

I'm of the opinion that beer needs some regular tap water. I have no scientific reasoning to back that, and many brew with 100% RO & mineral additions and have fantastic results. Maybe Martin Brungard can chime in on it. My beers just seem more rounded, fuller, and complex with its cut with a little tap.

 

[Silver_Is_Money]

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).

From some investigations, it was considered that acidification of the wort improved both the rate of lautering (see below) and the beer stability, but in at least two cases the beers produced from the acidified mashes were considered to have poor flavours being described as 'empty' and astringent, and it was felt that more attention needed to be paid to this aspect.

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

The point that peaked my interest here being that wort acidification is mentioned to improve lautering and stability, while for at least two test cases specific mention is made of mash acidification being detrimental to flavor (in the form of 'emptiness' and 'astringency'). And in no case of acidification is there mention of flavor benefit.

 

[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.

 

[user 246304]

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.

 

[user 246304]

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.

 

[user 246304]

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.