4 weeks in primary cause of banana flavors?

[teej_810]

i just kegged my dunkelweizen and after 4 days of carbonating and conditioning i tried a glass. and its has a strong banana flavor to it, nothing like i have had before and as strong as i have tasted.

the only thing i know that i did different was i left it in the primary for 4 weeks instead of my usual 2. i did this based on the general consesus that there is no need to secondary and i thought i would give it a shot. so could this be the reason for the strong banana flavor? did i have the beer sit too long on the yeast cake?

another note is i tried a sample before kegging and it had a slight banana flavor but it definitly got stronger after a few days in the keg

 

[bknifefight]

It probably has nothing to do with how long you kept it in the primary but rather with what temperature you fermented. With time it will mellow out, let it ride.

 

[Eastside Brewer]

A little more info would be good.....
Recipe? What yeast? What temp did it ferment at?

Eastside

 

[jmhart]

Definitely not from sitting in the primary for 4 weeks.

What was the yeast? That'd be my first guess.

Second guess would be fermenting too warm.

 

[teej_810]

definitly not fermenting too warm. never got above 68, mostly around 64. i used wyeast 3068

 

[Eastside Brewer]

Estery / Fruity
Ales are supposed to be slightly fruity, and Belgian and German wheat beers are expected to have banana flavor components, but sometimes a beer comes along that could flag down a troop of monkeys. Esters are produced by the yeast and different yeast strains will produce different amounts and types. In general, higher fermentation temperatures produce more esters. Next batch, contrive to lower the fermentation temperature by a few degrees.

Estery/Fruity
Tastes/Smells Like:
Fruit, especially banana, to a lesser extent, pear, strawberry, raspberry, grapefruit
Possible Causes:
Esters are a naturally occurring byproduct of fermentation. Certain ales are supposed
to have these fruity flavors, such as Belgian ales and Hefeweizens (German Wheat
beer) and certain types of yeast produce more esters than others. Strong fruity flavors
or fruity flavors that are inappropriate for the style of beer are sometimes a result of
under pitching or high fermentation temperatures. As a general rule, the higher the
fermentation temperature, the more esters the yeast will produce. In addition to high
fermentation temperatures, low oxygen levels can also help increase the production
of esters.
How to Avoid:
Always pitch enough yeast for the gravity of your beer and oxygenate well. Keep
fermentation temperatures under 75ºF when possible. Fermenting over 75ºF has
been shown to drastically increase esters. Fermenting between 60F – 65F will reduce
ester production considerably, however, be prepared for a slower fermentation. Lastly,
always use the correct yeast for the style of beer being brewed. Yeast strains made for
Belgian or German wheat beers are made to produce fruity characteristics, so if you
are trying to avoid beers that taste like bananas, avoid using these strains.
MoreBeer!™ www.MoreBeer.com “Off” Flavors, Their Causes and How to Avoid Them

Just a few sources to consider, hope this helps.

Eastside

 

[martinworswick]

i thought a banana flavour was a desirable characteristic of a dunkelweisen?

 

[Eastside Brewer]

Back to Yeast Strain List

The classic and most popular German wheat beer strain used worldwide. This yeast strain produces a beautiful and delicate balance of banana esters and clove phenolics. The balance can be manipulated towards ester production through increasing the fermentation temperature, increasing the wort density, and decreasing the pitch rate. Over pitching can result in a near complete loss of banana character. Decreasing the ester level will allow a higher clove character to be perceived. Sulfur is commonly produced, but will dissipate with conditioning. This strain is very powdery and will remain in suspension for an extended amount of time following attenuation. This is true top cropping yeast and requires fermenter headspace of 33%.

Origin:
Flocculation: low
Attenuation: 73-77%
Temperature Range: 64-75° F (18-24° C)
Alcohol Tolerance: approximately 10% ABV


Styles:
Dunkelweizen
Fruit Beer
German Hefe-Weizen
Roggenbier (German Rye Beer)
Weizen/Weissbier
Weizenbock

DUNKELWEIZEN



AKA:
Dunkelhefeweizen, Dunkelkristallweizen, Dark Wheat Ale

Pronunciation guide for English-speakers:
"doonn-kel vite-sen" (pronounce the "oo" short as in "foot")

Definition:
Dunkelweizen is the dark version of the regular golden-yellow Weissbier or Weizenbier (more commonly called Hefeweizen in North America), the spritzy, creamy Bavarian wheat beer with pronounced clove, vanilla, banana, apple, bubblegum, and sometimes nutmeg flavors. Dunkel means dark in German (as opposed to weiss, which means white) and Weizen means wheat. Like a Hefeweizen, Dunkelweizen is made from a mixed mash of wheat and barley malts, but unlike a Weissbier, it also contains a large array of lightly to thoroughly caramelized or roasted malts that give it both its color and its complexity. A Dunkelweizen, therefore, has all the characteristic and differentiated flavors of a sophisticated wheat ale, overlaid with chocolatey to roasted flavors. Dunkelweizen is a very complex beer style with endless variations on the same theme. There are dozens of brands of Dunkelweizen in Bavaria, each with its own, very individual, flavor orientation, and several brands, inlcuding Schneider Aventinus and Erdinger (depicted) are exported to the United States. For more on German wheat beer brewing, see Weissbier.


Eastside

 

[rjwhite41]

So, if overpitching eliminates the banana I would assume that underpitching would increase it. Did you make a starter?

 

[teej_810]

goood replies eastside. very good info. i always known that hefes and wheat beers will have this estery taste but this is kinda too much for me. i'll let it age for a bit and see what happens but right now i"m not looking forward to drinking this one. i only decided to brew this cuz i liked sam adams dunkel and so far mine is not a winner.

 

[D0ug]

definitly not fermenting too warm. never got above 68, mostly around 64. i used wyeast 3068

Was that fermenter or ambient temperature?

 

[teej_810]

fermenter. ambient temp never gets above 70 right now. (live in new england)

 

[Powers]

So, if overpitching eliminates the banana I would assume that underpitching would increase it. Did you make a starter?

there's a little cross info on this point. overpitching tends to reduce ester production and lead to a fast fermentation that can stymie the production of esters and other flavors that are often desireable in an ale, especially a german wheat like a dunk.

but, i've also seen that longer exposure to the yeast can lead to more esters. so, if you left it on the yeast cake for 4 weeks, it seems that could allow the production of more banana-like flavors than if you had racked it at 2 weeks. i'm presuming that a small yeast cake will still be present in the secondary, though much less.

eastside's post notes that low oxygen can be a cause, did you aerate your wort prior to pitching?

 

[D0ug]

your fermentor temps were 2-6 degrees below ambient? They are usually 5-10 degrees above ambient, you must have temp control! Cool, swamp cooler?

I know when I used fermentis wb-06 I got a lot of banana from fermenting at 66*F ambient. And that was present with in a week or so from pitching. That's what I wanted for that brew though, a lot of my friends are adverse to cloves. A lot of people have said that using wb-06 at cooler temps, like 60-62, gave more cloves.

That was one time when I racked to a second bulk container after a month. I gave it another 3 weeks to let some of the banana mellow out, and that helped a lot.

 

[kopher]

I realize the OP kegged so this isn't super relevant, but one of my first beers was a dunkelweizen and I thought it would be fun to prime with brown sugar...it was the craziest mess of bananas foster I have ever tasted -- but it was delicious.

 

[Powers]

from a description of wyeast's bavarian wheat 3068 (the Weihenstephan strain), the bold portion referring to the discussion of ester production and underpitching:

"Classic German wheat beer yeast, used by more German brewers than any other strain. Dominated by banana ester production, phenols and clove-like characteristics. Extremely attenuative yeast, which produces a tart, refreshing finish. Yeast remains in suspension readily with proteinaceous wheat malt. Sometimes used in conjunction with lager yeast and kraeusened to finish the beer and improve the overall dryness. High CO2 levels, typically at 2.7 - 3.2 volumes is desirable for best presentation. This strain is a true top cropping yeast requiring full fermenter headspace of 33%. Increasing pitch rates will reduce ester production."

 

[Eastside Brewer]

goood replies eastside. very good info. i always known that hefes and wheat beers will have this estery taste but this is kinda too much for me. i'll let it age for a bit and see what happens but right now i"m not looking forward to drinking this one. i only decided to brew this cuz i liked sam adams dunkel and so far mine is not a winner.

+1 on letting it condition for a while. Not sure how long it's been, but a little more time never hurts.

Good luck with it.

Eastside

 

[BryanJ]

I've used that yeast on three separate batches which all were different styles and they all had a hint of the banana esters. They mellowed with time but i still notice them, but then again i enjoy these esters.