Avoiding Fusels

I'm getting frustrated. Nearly every batch I brew has a touch of fusel alcohol. Sometimes, more than a touch. My most recent, 10 gals of EdWort's Haus Ale has the same issue. Actually only half of it does. I spit the batch in half to ferment in two six gallon carboys. They sat side by side for ten days in a cooler filled with water and floating ice packs, covered with wet towels. The thermometer in the cooler never exceede 68 degrees. The batch from one has mild fusel hotness, the other does not. I did not notice it until after the two halves had been in the kegs for several days.

My process: Mash for sixty minutes at 152. Fly sparge at 170 (takes about 40 minutes). One hour boil. Cool with immersion chiller. Rack and pitch. Dry yeast this time with no hydration and no starter. (But I get fusels with White Labs and starters too.). Filter after primary and keg. I know my fermentationj temp never exceeded 70 degrees.

What is the best way to avoid production of fusels? I'm ready to try anything. Should I be racking off the trub sooner? Or skimming the krausen???

Thanks for your thoughts.

John

How do you know it has fusels? Hangover? Taste? If so, what do they taste like?

The other likely cause of fusels in excessive amounts of yeast, or too much yeast contact time:
http://www.howtobrew.com/section4/chapter21-2.html

A sharp flavor that can be mild and pleasant or hot and bothersome. When an alcohol taste detracts from a beer's flavor it can usually be traced to one of two causes. The first problem is often too high a fermentation temperature. At temperatures above 80°F, yeast can produce too much of the higher weight fusel alcohols which have lower taste thresholds than ethanol. These alcohols taste harsh to the tongue, not as bad as cheap tequila, but bad nonetheless.

Fusel alcohols can be produced by excessive amounts of yeast, or when the yeast sits too long on the trub. This is one reason to move the beer off of the hot and cold break when the beer is going to be spending a lot of time in the fermentor.

Click to expand...

If that's not the problem (as suggested by your side-by-side fermentation test) maybe these might not be fusels? Could it be some medicinal or solvent-y phenolic compounds, either from residual cleaning chemicals, plastic contact, or some sort of infection?

Just noticed you didn't mention a secondary.. maybe that will help a little. Take it off the primary after a week and moving to a clearing fermenter.

Fusels are a symptom of stressed yeast. Warm temperatures, especially in combination with too little yeast or poorly aerated wort, are the typical cause. You generally never hear of anyone attributing it to over-pitching (you would have to pitch obscene amounts of yeast) or from effects of trub/lack of a secondary.

Here is my advice (based on a number of fusel-ridden batches):
- be SURE you are ferementing cool enough. Even if ambient temps are 70F, the yeast will generate heat of its own up to 10 degrees higher (I didn't know this before and it was the cause of my problem). Admittedly, though, a water bath should help.
- always pitch enough yeast and aerate really well so that yeast aren't stressed, particularly for higher gravity beers
- protect your beer from temperature fluctuations (fermenting in your water bath should help, assuming there is a good volume of water there)

Despite what many people will tell you, the good news is that the hot-alcohol taste of fusels will begin to disappear over time, if you are patient. The bad news is that it takes months (not all beers will last this long), and it never goes away completely.

Hope you get it figured out. If/when you do, please post back to this thread so we can hear what you did to solve things.

Cheers!

FlyGuy said:

Fusels are a symptom of stressed yeast. Warm temperatures, especially in combination with too little yeast or poorly aerated wort, are the typical cause. You generally never hear of anyone attributing it to over-pitching (you would have to pitch obscene amounts of yeast) or from effects of trub/lack of a secondary.Cheers!

Click to expand...

And I'll agree to this. From the time your yeast is first pitched until the first signs of fermentation is when the majority of fusels are produced.

boo boo said:

And I'll agree to this. From the time your yeast is first pitched until the first signs of fermentation is when the majority of fusels are produced.

Click to expand...

If indeed it is fusels your getting, I think boo boo and Fly Guy have it. What is your wort temp post chilling? If you are pitching and then cooling to 68-70F you could see fusels since fermentation starts before you see actual activity, i.e., bubbling/kraeusen.

OTOH, as careful as you are being, it could be another flaw you are detecting.

I suggest having someone else sample your beer for you without telling them of your persepted flaw. May be just flavours you yourself are sensitive to, I really can't see fusels being produced in near enough quantity to be a flavour issue

Its really not a flavor I detect, but rather a sensation. There is a distinct hotness on the tongue, gums and throat. There really isn't a medicinal or solvent-like taste, which makes me doubt that residual cleaning solution is to blame. I never use bleach, just Oxy to clean followed by a hot water rinse and Starsan to sanitize.

I do pitch at around 70 degrees, and then reduce the temp after I notice activity, but never pitch anywhere near 80 degrees. I think I will try chilling to sixty-five before pitching, and just deal with the slow start.

I think I will also try skimming the "crust" off the krausen as well. I've heard it suggested that the best way to avoid fusels is to rack off the trub BEFORE you pitch. I've always been affraid to wait that long to add the yeast. Anyone ever try that?????

Thanks for the advice.

JG

swampdog said:

I think I will also try skimming the "crust" off the krausen as well. I've heard it suggested that the best way to avoid fusels is to rack off the trub BEFORE you pitch. I've always been affraid to wait that long to add the yeast. Anyone ever try that?????
JG

Click to expand...

That's a nice invitation for infection. The reason for pitching early is to head off any chance for bugs to get going in your wort. Unless your sanitation is
the best ever, then I would suggest you avoid waiting to pitch yeast and not to try skimming the krausen.
Anyway, fussels are caused by high starting tempertures of the yeast/wort,
and weak yeast, like was already stated.