Fusels and how to get rid of them?

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Desert_Sky

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Yea so you forget to wet the towel around the carboy for two stinking days and the temp goes up higher than it should. Do the yeast let it slide? Noooo, they get all pissed off and made all sorts of fusel alcohol in my beer. Now, my beer tastes like Im doing a shot of liquor, which some may say is ok, but its bothering the hell out of me.

Anyway to salvage this batch?
 
The conditioning that takes place during secondary fermentation can clean up some off flavors associated with high temp primary fermentation, such as acetaldehyde and diacetyl, but unfortunately not much can be done for fusels and esters.

John
 
Just out of curiosity (and for the sake of education) how much higher did the temp go?


Tommy
 
Brewno said:
Just out of curiosity (and for the sake of education) how much higher did the temp go?


Tommy


The stick on thermometer on the carboy read 74-76. So it may have been a bit higher. It was a real vigorous one too, so Im sure it was producing it's fair share of heat.

well since not much can be done about it, i went ahead and threw it in the fridge. Maybe Ill forget about it, and in a couple weeks, taste it again to see if that helped.
 
That doesn't sound that high....and that worries me. What kind of yeast?
Those stick on thermometers seem tricky to me. I have a wet towel on my secondary right now but I'm concerned about the temp when it was in primary. I think it was the same as yours...74 to 76. I used Wyeast 1056 American ale which said 70-75.
It's been so hot that even with the towel it only dropped 2 degrees in two days and is now down to 72. My A/c is only getting the house down to 80 and sometimes 79!!

I'm starting to wonder if that may be what caused the off taste (slight) in my first batch.

Thanks and sorry to hear about that

Tommy
 
Yeah, I've had temps go that high before without seriously bad effects (not to say that it couldn't happen, however). Did you pitch a large amount of yeast and aerate the wort well? Both of those can lead to fusels and esters.
 
Baron von BeeGee said:
Yeah, I've had temps go that high before without seriously bad effects (not to say that it couldn't happen, however). Did you pitch a large amount of yeast and aerate the wort well? Both of those can lead to fusels and esters.


well I aerate by dumping cool wort through a strainer and shaking. It usually works really well. Lots of foam before I pitch. This time i didn't let it get down to fermenting temps before I pitched. I dumped the starter of WL001 at around 80ish figuring it would cool before it started. I had to work 12 hours a day for 4 in a row, so it never really got to cool down enough. It was on it's way down to temp like they all do, but like I said, I missed wetting the towel the two most important days.

If the thermometer said 76, it was probably 2-3 degrees higher in the middle. It was a vigorous fermentation, so lots of heat was produced from it.

Ive had one other with slight fusels (its been a hot summer up until recently), but as it aged, the alcohol flavor went away. I as hoping this one would too.
 
So, you think the cooler air surrounding a stick-on thermo will effect the display temp? Do an experiment and throw a thick towel around the carboy? See if theres a diff. after a few hours.
 
Exo said:
So, you think the cooler air surrounding a stick-on thermo will effect the display temp? Do an experiment and throw a thick towel around the carboy? See if theres a diff. after a few hours.

This is an interesting question as well as an interesting thread.
I'm now curious about the stick on because I have one on my carboy which is covered in a wet T-Shirt in a basin of water. I have the thermometer covered with clear tape to protect it from contact with the water. It reads 72 deg.
So now I'm wondering if that's the beer/carboy temp or the wet T-shirt?
My basement is now about to pass 80 deg. ....it's damn hot around here this week! My basement is underground which makes it odd, but I'm guessing it may be because it's connected to the garage which is like an oven.

Now this all leads to another question. What about bottling? How will this heat effect conditioning? How would you keep the bottles cool?
I have a Hop Devil clone in secondary, do the hops help, at least a little, in warding off any off flavors?

Tommy
 
Exo said:
So, you think the cooler air surrounding a stick-on thermo will effect the display temp? Do an experiment and throw a thick towel around the carboy? See if theres a diff. after a few hours.


well from what ive read, and my experience with terreriums, and aquariums, the surface temp is a tad lower (not much mind you) but its not the temp in the middle.
 
Well, in a primary the beer is churning around so much, there could not possibly be any areas of the liquid that are warmer than the others. So the temp in the center should be dang close to the temp along the carboy walls.

And when the yeasties settle and you have a difference of temp. in the carboy and outside the carboy (such as a water bath) the liquid near the carboy walls will fall ever so slowly due to having just been cooled by the water bath/etc.

Surface temp of a static liquid container will be lower...due to evaporation, offset by warmer liquids rising to the top. But we're working with closed containers...still I lose volume over several weeks...probably due to the newly made CO2 absorbing the humidity of the closed container then escaping through the airlock.
 
true, good point. maybe someone will chime in who knows for sure.

So anyone who reads this feel free to give your .02 cents.

Is the temp on the outside of the carboy the same as the temp on the inside?????
 
In my experience in aquariums, depending on the thickness of the glass, the stick on thermos can read closer to the outside room temperature rather than the liquid inside, or a compromise between the two temps. Not really accurate, IMO.
 
One thing about fermentations and high temps is that they can 'run away' out of control. It's pretty difficult for a homebrewer to control higher fermentation temps the way some commercial breweries can (such as ones brewing Belgian ales at higher temps). I used to pitch as soon as possible for all the well publicized reasons, but I'm now of the opinion that I prefer to cool all the way to my preferred fermentation temp before pitching, even if it takes hours. I'm rigorous with my sanitation to balance the risk of an infection taking hold. This way I can avoid unwanted esters and fusels which is the payoff.
 
In a way I can't wait till thew fall. mbient temp has be really high here. Even with the AC in I can't get a temp less than 21c or 70f.

So add in the yeasties burning through sugars... Switched to a dry yeast called Mauribrew for a batch to see how that fairs since it is suppsed to run really clean even up to 86F! I've been told that is not an exagerated claim by a number of Aussie brewers on Aussie brewing forum.
 
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