Esters in my Beer

The last couple batches I brewed that were lightly hopped have had a noticeable banana flavor to them. I figure this is an ester caused by the yeast and the only information I can find about it suggests the production of these esters is likely related to high temperature during fermentation. I can understand with my frivolous processes in the past how this could be the case, but I have made a new set up in my basement which should provide much better temperature control. However, there are a couple of factors which make me think that maybe I just willy-nilly do things to my beer in fear for their health, which just ends up hurting them:

- I moved the beer from the basement to the main floor after a week in the bottle because I was afraid it was actually too cool down there for them to condition. On the high side I don’t think it would get more then mid 80’s in here.

- My concern is based off a premature sample I had last night. To be fair they need at least another three days in the bottles before they should be ready to drink.

I am going to put them back down in the basement and let them condition fully. I’m hoping that banana flavor goes down, but in case it doesn’t I’m wondering if anyone has any helpful advice regarding those damned esters, or a source or two on them.

Certain yeast strains produce lots of esters. Another thing that might have happened was poor aeration when you pitched.

As far as temp goes, we'd need to know what yeast you used. But keep in mind the temp of the beer will usually be a few degrees higher than the ambient temp.

Esters are a normal ale yeast fermentation by-product, the amount of which is influenced by specific strain, fermentation temperatures, specific gravity, wort aeration, etc.

I used White Labs English Ale yeast WLP002. What is a good way to aerate my wort without an oxygen pump or any of that stuff? I usully try to shake the hell out of it but maybe I should focus a little more on this part.

ThinkinDavid said:

I used White Labs English Ale yeast WLP002. What is a good way to aerate my wort without an oxygen pump or any of that stuff? I usully try to shake the hell out of it but maybe I should focus a little more on this part.

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Did you make a starter? Ester formation is also a stress response from the yeast - be it unregulated fermentation temperature or difficulties in adapting to wort conditions.

i would suggest letting the wart ferment for at lest 2 weeks before bottling to allow the yeast time to cleanup after themselves. make sure you aerate enough. keep the fermenter somewhere in the 60s. don't add refined sugars to your wart. keep the bottled beer in the 60s during carbonation for 2 weeks. then the beer should be good to stick in the fridge and drink.

flyangler18 said:

Did you make a starter? Ester formation is also a stress response from the yeast - be it unregulated fermentation temperature or difficulties in adapting to wort conditions.

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I did make a starter and I'm wondering if I should keep that in the basement as well.

From what I've read I don't know that keeping the beer in the fermentor for a longer period of time will help. It seems like doing this may clean up any diacetyl but not necessarily the esters. It seems to me that my fermentation temperatures were just way too high. I see now that the white labs site says the optimum fermentation temperature for my yeast is between 65-68 degrees which is way lower than what it was fermenting at. There is a concurrent thread, right now, with this one that is talking about submerging your fermentor in cold water. I think this might be my solution.

ThinkinDavid said:

I used White Labs English Ale yeast WLP002. What is a good way to aerate my wort without an oxygen pump or any of that stuff? I usully try to shake the hell out of it but maybe I should focus a little more on this part.

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Go to petco and buy an air pump like you would for a fish tank and stick a hepa filter in the line like this one: Austin Homebrew Supply.

ThinkinDavid said:

I did make a starter and I'm wondering if I should keep that in the basement as well.

From what I've read I don't know that keeping the beer in the fermentor for a longer period of time will help. It seems like doing this may clean up any diacetyl but not necessarily the esters. It seems to me that my fermentation temperatures were just way too high. I see now that the white labs site says the optimum fermentation temperature for my yeast is between 65-68 degrees which is way lower than what it was fermenting at. There is a concurrent thread, right now, with this one that is talking about submerging your fermentor in cold water. I think this might be my solution.

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I have a giant round tub that I fill with water and set my carboy in. A little ice in the morning and night keeps the temp right where I want it, with 2-3 degree fluctuations.

coryforsenate said:

I have a giant round tub that I fill with water and set my carboy in. A little ice in the morning and night keeps the temp right where I want it, with 2-3 degree fluctuations.

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Well hot damn! My confidence is back up, I'm ready to brew again! Thanks everyone.

Yeah, mid 80s is pretty damn high; I would guess that it's your main problem, not aeration.

This looks like a fun way to aerate.....

[ame=http://www.youtube.com/watch?v=10W_U3-UOlc]YouTube - Home brew Beer, Oxygenate or Aerate Your Home Brewed Wort.[/ame]

Albiet, the guy then has to take that stuff into his glass primary.... I don't think you'd want to use that on your plastic primary for fear of scratchign the **** out of it.

Cheaton said:

This looks like a fun way to aerate.....

YouTube - Home brew Beer, Oxygenate or Aerate Your Home Brewed Wort.

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That cracks me up, but I don't have a plastic bucket to aerate from.

Ester's in my Beer...tell her to get the fukk out!!!

Just an indicator of higher fermenting temps...

coryforsenate said:

I have a giant round tub that I fill with water and set my carboy in. A little ice in the morning and night keeps the temp right where I want it, with 2-3 degree fluctuations.

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Same here. I can vouch for this method in the summer time. If it gets really hot put a t-shirt over your bucket and let the bottom half drape into the water. The cold water will wick up into the shirt and cool the whole set up.

I sub out the ice and add an aquarium heater in the winter time to keep temps up...still in the ideal range though.

-Tripod