Off Flavors in Darker Beers

Hello all!

I've been brewing for a few years now and I've mainly stuck with the lighter-colored ales - blonde ales, pale ales, IPAs, etc. However, in each of the 3 darker beers that I've attempted to make (red ale, coffee stout and bock), each had what can be considered a harsh "sweetness" (perhaps even a bitterness) to it. I don't get this with the other "lighter" styles. I had assumed that this was becuase I was mashing at slightly higher temps and this was unfermentable sugar. I've always been careful not to mash higher than 153 or 154. I've even left the batches in the bottle for upwards of 6 weeks and the "flavor" doesn't go away. Has anyone else noticed this? Should anything be done differently process wise when using the darker malts? These have all been partial mash (actually close to quasi-all grain) recipes using anywhere between 5 to 12 pounds of grain. I've also tried to ensure that I ferment low to avoid off flavors from the yeast.

Thanks in advance,
Andrew

What is your water profile? Water treatment (or lack of) could contribute to that.

I've actually never messed with my water profile. I use either jugged drinking or spring water from the store and add a teaspoon of the 5.2 mash stabilizer.

Spring water/drinking water could have a strange water profile, depending on the source. I'd say it's probably pretty low in all the ions, although it could have weird surpluses in some. The manufacturer can give you the water profile, if you have specific brands you like to use.

Check this out:
http://www.themadfermentationist.com/2008/09/i-think-that-water-treatment-has-made.html

I used to use the 5.2 until I learned a bit more about water chemistry. Mash pH is only a small function of the water profile, and not the only reason to add brewing salts.

Since water is like 99% of beer, I develop a unique water profile for every beer I brew. My water is pretty low in carbonate, sodium and chloride. When doing dark beers before I would sometimes get an overly harsh burnt flavor, or a weird kind of sweetness, or both.

Now I add flavor ions to skew it towards the profile I want. It definitely takes a light touch. My first batch, I overdid it trying to copy Burton-on-Trent and it came out really metallic-y.

Have you ever made a cake or cookies and forgot to add salt? It tastes weird and the sweetness tastes wrong. The same thing happens with ions in beer. For sweet, malty beers, I'll add at least a small amount of salt, if nothing else.

I use Brewater 3.0 to calculate my ion additions.

Thanks, Nateo. I'll certainly have to try this!

Zombie thread time...

I have been having the same issue. My light beers turn out fantastic where my dark beers have a goofy off taste, but not undrinkable.

OP - did you ever get a solid resolution to your problem?

If light beers tend to turn out well and dark beers don't, the problem is most likely insufficient alkalinity in the brewing water. Do you know if the brewing water has low alkalinity? Low alkalinity can let the mash pH fall too low and the beer ends up sharp or overly tart.

mabrungard said:

Do you know if the brewing water has low alkalinity? Low alkalinity can let the mash pH fall too low and the beer ends up sharp or overly tart.

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Thanks for your reply!

Never tested the PH of my water because when I started home brewing, everything was coming out fine so I never thought of it. Then I started with dark beers and thought something could be wrong with my water profile...

I think I have hard water, because when I use my tap water to mix up star san, it goes cloudy in 2 days.

Its not the hardness that counts, its the alkalinity. In a way, hardness is counter-productive if there isn't enough alkalinity, it reduces the Residual Alkalinity of the water in the mash. That may not be what you want in the mash if brewing a darker beer.

The first step is to find out what your water quality parameters are and then do a little exploring with a program like Bru'n Water.

Cool, thanks for the tip!

Hey Unibrow, I'm the original poster of this thread. Thanks for resurrecting it!

To follow up (and to support mabrungard's advice), I brewed a nut brown ale in November of last year and the one major thing that I did was to use certain brewing salts to adjust the water chemistry. I think that this had a HUGE impact on the overall flavor. The chemistry of adding the salts is quite complex and has been discussed at length in the "Brew Science" section of this site. I learned about and used a spreadsheet called the EZ Water Calc 2.0 or something like that.

Without getting too much into it, once you obtain your water's profile (you can either get your water tested OR if your using city water, they typically publish annual reports) you can plug in the numbers and figure out which salts to add. As with any topic on this board, there are people who will fight tooth and nail as to the nuances, BUT I think the overall consensus is that this is a good starting point to fixing some of your brews.

At the end of last year (Dec. 30 I think), I brewed an ESB and also used the water calculation spreadsheet. Based on the numbers, I ended up using 1/2 local water and 1/2 Distilled water and then added salts from there. I'm going to be bottling it soon, but I'm pretty confident that it will be good!

Cool, thanks Ahoff. Glad you got it figured out

I'm hesitant to start screwing with my water chemistry at this exact moment because:
A) I have made amazing beer using ONLY my tap water (mash, sparge, top off)
B) I prefer light beers to dark beers anyway
C) I am only 6 months into this hobby, and still getting other variables under complete control first

However - I want to get this figured out eventually, so I'm going to try making a dark beer by mashing with spring water, and that should give me my definite answer. Then i'll go back to water chemistry if I feel it's necessary.

Any other suggestions you have, lemme know. Thanks

Spring water is not a guarantee to success. If you can find out what is the particular spring water you're thinking of using, then you could better assess how it might perform for you. Of course, you can just go ahead and brew with it and see how it turns out. Hopefully it would be better than your previous results.

mabrungard said:

Hopefully it would be better than your previous results.

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Yeah, this is what I'm hoping. Still not sure yet. Thanks for the reply

Uni,

I can totally sympathize with you not wanting to jump into the water chemistry thing right away - after all it is quite daunting. At 6 months into the hobby, I too was more worried about my process, etc. BUT from my perspective, the LACK of the water chemistry being added to my normal routine got me very frustrated very quickly as spending all the time and effort (and MONEY) to make sub-par beer just didn't seem worth it! And, if your lighter beers are great, they may even be BETTER by adjusting the water.

Anywho, that's just my $.02. Experiment, have fun and keep up the good effort. After all this is what this hobby is all about! Let us know if you have any more insights!

mabrungard said:

Spring water is not a guarantee to success. If you can find out what is the particular spring water you're thinking of using, then you could better assess how it might perform for you. Of course, you can just go ahead and brew with it and see how it turns out. Hopefully it would be better than your previous results.

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sooooo.. Is there a collective experience on which brands of bottled water require the least adjustment? I haven't addressed water ammendments yet.

I use Deer Park spring water - here are the stats below. Anything jump out as really bad for brewing? Let me know, thanks

Regarding Deer Park or any of the major national water brands, they take water from a variety of springs on a regional basis. That is why the report above has such a range in ions. Most of the ions have little variation and you could just use an average value and it would be fine. The 2 ions that matter are calcium and bicarbonate. They have pretty high variability from source to source as evidenced in the table. Not too good for planning your next brew on.

If you can find a bottled water source that comes from a single spring and can get its water profile, then you have something to work with.

The spring water I bought at Walmart lists the source as "Fort Worth Municipal" - basically, I'm buying Fort Worth city water. (I live south of Dallas).

But, I was able to pull up a semi-recent water report from the Fort Worth city website. This seemed to work just fine for me.

Add the dark/roasted malts at mash-out or vorlauf.

maffewl said:

Add the dark/roasted malts at mash-out or vorlauf.

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Really? No mashing the dark malts? This idea is intriguing...

It depends on the alkalinity of your water... but for all my darker beers, I either cold steep (2 quarts/lb. of dark malt, in the refrigerator overnight, add at boil) or I add the dark malts at mash-out. The quality of beer since has improved dramatically.

mabrungard said:

If light beers tend to turn out well and dark beers don't, the problem is most likely insufficient alkalinity in the brewing water. Do you know if the brewing water has low alkalinity? Low alkalinity can let the mash pH fall too low and the beer ends up sharp or overly tart.

Click to expand...

First off, low alkalinity is desired. High alkalinity extracts astringent, harsh, bitter, and colored substances from raw materials. Hardness, gained from calcium and magnesium ions in the water has the effect of reducing the pH of the mash and wort. This lower pH favors mash enzymes and there is some improvement in extract yield, better and more rapid mash/wort separation, superior formation of breaks during boiling, and possibly more rapid onset of fermentation. By adding salts like so me people have said, you are increasing the hardness of the water which is beneficial to the mash.

Unibrow said:

Zombie thread time...

I have been having the same issue. My light beers turn out fantastic where my dark beers have a goofy off taste, but not undrinkable.

OP - did you ever get a solid resolution to your problem?

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You could try adding your dark grains during mash out or your first vourlauf. This technique is supposed to help remove some of the harshness that can come from mashing dark grains. You also could start with RO water and add some calcium chloride and chalk

flabyboy said:

You could try adding your dark grains during mash out or your first vourlauf. This technique is supposed to help remove some of the harshness that can come from mashing dark grains. You also could start with RO water and add some calcium chloride and chalk

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I sparge in my bottling bucket. Usually about 3 gallons of sparge water for 8-10 pounds of grain at 170 degrees, for 10 minutes.

If I follow y'all correctly, you're saying to NOT include my dark grains (brown malt, chocolate malt) in the original 70 minute mash mash. But to add those darker grains to my sparge, built with with RO water + calcium CL and chalk?

From this method, am I right to presume that darker grains do not add any fermentables, but only add flavor and color?

XpeedeeX said:

First off, low alkalinity is desired. High alkalinity extracts astringent, harsh, bitter, and colored substances from raw materials. Hardness, gained from calcium and magnesium ions in the water has the effect of reducing the pH of the mash and wort. This lower pH favors mash enzymes and there is some improvement in extract yield, better and more rapid mash/wort separation, superior formation of breaks during boiling, and possibly more rapid onset of fermentation. By adding salts like so me people have said, you are increasing the hardness of the water which is beneficial to the mash.

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The dark roasted grains when mashed can drop your pH below ideal levels. This is not a concern when using only light malts

flabyboy said:

The dark roasted grains when mashed can drop your pH below ideal levels. This is not a concern when using only light malts

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This could be the piece of information I've need all along...

Unibrow said:

I sparge in my bottling bucket. Usually about 3 gallons of sparge water for 8-10 pounds of grain at 170 degrees, for 10 minutes.

If I follow y'all correctly, you're saying to NOT include my dark grains (brown malt, chocolate malt) in the original 70 minute mash mash. But to add those darker grains to my sparge, built with with RO water + calcium CL and chalk?

From this method, am I right to presume that darker grains do not add any fermentables, but only add flavor and color?

Click to expand...

Not exactly. Don't add them to mash. Wait until you are done mashing. Open the lid, put your dark grains in and add your mash out water and stir or start your vourlauf with the sparge water. Basically put the dark grains on top of the mash not into your sparge water. Make sense??

flabyboy said:

Not exactly. Don't add them to mash. Wait until you are done mashing. Open the lid, put your dark grains in and add your mash out water and stir or start your vourlauf with the sparge water. Basically put the dark grains on top of the mash not into your sparge water. Make sense??

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It makes sense conceptually...but I have barely any room in my mash pot (20 quarts) to add more grains, let alone mash out water. I need to sparge in a separate vessel, and all I have is another bucket.

the flavor your describing is tannins from the husks of the dark roasted grain. high precentages in the grain bill will increase this effect, also when you partial mash these grains you run the risk of channeling your sparge which i suspect is your root problem of the flavor you taste, to help this problem try CarafraI, II or III these grains are like chocolate, black patent and roasted barley. but they are huskless and do not give that strong pinch that regular roasted malt do. tr

Unibrow said:

It makes sense conceptually...but I have barely any room in my mash pot (20 quarts) to add more grains, let alone mash out water. I need to sparge in a separate vessel, and all I have is another bucket.

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You could just do it at vourlauf and skip the mashout. Sounds like you need a bigger MLT

flabyboy said:

You could just do it at vourlauf and skip the mashout. Sounds like you need a bigger MLT

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I do BIAB and can mash up to 10# of grains with 70-75% efficiency in my pot. So i don't really vorlauf or mashout per se. I forget what the procedure is called, but my grain bag is like a giant tea bag. When it's time to sparge, I pull the bag out of my stock pot and dunk it in&out the 3 gallons of sparge water for 10 minutes. It may not be the best way of doing all grain, but it's been working very good for me.

So maybe the darker grains should go into the dunking sparge part? I can check around and see if other people have tried this.

XpeedeeX said:

First off, low alkalinity is desired. High alkalinity extracts astringent, harsh, bitter, and colored substances from raw materials. Hardness, gained from calcium and magnesium ions in the water has the effect of reducing the pH of the mash and wort. This lower pH favors mash enzymes and there is some improvement in extract yield, better and more rapid mash/wort separation, superior formation of breaks during boiling, and possibly more rapid onset of fermentation. By adding salts like so me people have said, you are increasing the hardness of the water which is beneficial to the mash.

Click to expand...

I think you have things misconstrued. Neither high or low alkalinity is desired. The correct alkalinity to coordinate with the mash's acidity IS desired.

All the information mentioned by XP above is correct. Its too bad they mis-applied it in this case. Coordinating the proper mash water alkalinity with the mash requirements will help avoid problems with either high or low pH. That means that more alkalinity might be needed for some beers and less in others.

Unibrow said:

I do BIAB and can mash up to 10# of grains with 70-75% efficiency in my pot. So i don't really vorlauf or mashout per se. I forget what the procedure is called, but my grain bag is like a giant tea bag. When it's time to sparge, I pull the bag out of my stock pot and dunk it in&out the 3 gallons of sparge water for 10 minutes. It may not be the best way of doing all grain, but it's been working very good for me.

So maybe the darker grains should go into the dunking sparge part? I can check around and see if other people have tried this.

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Another option is to steep dark grains separately like you would with specialty grains in extract kits. 2qts/ lb grain. Then add the liquid during boil

flabyboy said:

Another option is to steep dark grains separately like you would with specialty grains in extract kits. 2qts/ lb grain. Then add the liquid during boil

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This is brilliant...I know it's been stated before, but these forums are so helpful, fun and engaging. Thanks to all for their suggestions and comments here.

Unibrow said:

This is brilliant...I know it's been stated before, but these forums are so helpful, fun and engaging. Thanks to all for their suggestions and comments here.

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I got all this info from Gordon Strong's book. Brewing Better Beer. It's good. Give it a read