Fermenting in a keg.

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Lowlyric

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Does anyone have any experience with fermenting in a keg and leaving the beer on the yeast cake, carbing and servings. I know you need a floating dip tube but didn't know how it would effect the flavor of the beer.
 
Unless you intend to empty the keg pretty quickly, you'll eventually get some nasty off flavors from dead yeast. Just pressure transfer to a second keg for serving. You'll loose about a half gallon to yeast trub in a 5 gallon batch.
 
I ferment and often serve from a modified 1/4 barrel tall Sanke keg. The floating dip tube is the key to why it works so well. As far as leaving the beer on the yeast cake, I have done it for over a month after the fermentation was done with little or no off flavors. I normally wouldn't do that, but it was an IPA and I didn't want to transfer it to another keg.

I brew a lot of lagers. I ferment, clear and lager in the same vessel. I know it's best to get the beer off the yeast cake, but it is not unusual to have the beer in the fermenter for 3-4 weeks on the yeast cake with no off flavors. I think the key is getting it down as close as you can to 32F (0C) without freezing after fermentation is done. It seems to keep the autolyse of the yeast from happening and that's where the off favors come from.

I also try to keep as much of the cold break out of the fermenter to keep from loosing too much beer as JA mentioned above. Some brewers believe removing most of the cold break improves the beer, but I'm not convinced it's entirely true.

Fermenting in a keg has some big advantages over other fermenters available to home brewers. Pressure fermentation, spunding, closed transfers and the ability to get pressures higher than the typical 15 psi (that most fermenters are capable of) are the biggest advantages of keg fermentation. Sometimes I spund a beer to @ 30 psi. I do this because the beer is at 65-68F and that's the pressure needed to get decent carbonation. It also speeds up the whole process because the beer is fully carbonated at the end of fermentation.

Good luck and happy brewing!
 
Am I correct in assuming you need to remove the dip tube from the fermenting keg to avoid transferring the trub? Or use a shortened tube?
 
J A said:
Unless you intend to empty the keg pretty quickly, you'll eventually get some nasty off flavors from dead yeast. Just pressure transfer to a second keg for serving. You'll loose about a half gallon to yeast trub in a 5 gallon batch.
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Second this. wouldn't leave it in there unless it is going to empty in a week or two
 
Lowlyric said:
Am I correct in assuming you need to remove the dip tube from the fermenting keg to avoid transferring the trub? Or use a shortened tube?
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You would need to replace the dip tube with a floating dip tube. Even a shortened dip tube would be too long unless you rack to a serving keg first.
 
Lowlyric said:
Am I correct in assuming you need to remove the dip tube from the fermenting keg to avoid transferring the trub? Or use a shortened tube?
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I don't think i would use a floater for the fermentor keg.
 
I'm referring to the metal dip tube on the out post. If you pressure transfer with the tube in the fermenter it will be in the trub. No?
 
Lowlyric said:
I'm referring to the metal dip tube on the out post. If you pressure transfer with the tube in the fermenter it will be in the trub. No?
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I shortened mine and bent the ends at about 110°. keeps out the goo
 
Lowlyric said:
Am I correct in assuming you need to remove the dip tube from the fermenting keg to avoid transferring the trub? Or use a shortened tube?
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You need this for the fermenter:
https://www.amazon.com/Ferroday-Flo...cphy=9019630&hvtargid=pla-2281435179738&psc=1

I use this with a 7/16" stainless steel nut over the tube on the float. This keeps the end of the tube from flipping up and blowing gas instead of dispensing beer. The extra weight helps a lot.

I been using this for @ 6 years and it works very well. No trub until the very end. If you transfer to another keg, you pull the pop-up valve before any trub makes it in. Don't fret the beer on yeast too much. I've won many medals, including several best of shows and at the National Homebrew Comp with a beer that sat on yeast 3-4 weeks (includes time fermenting). Any longer is a bit risky.

Sometimes yeast will clog the dispensing tube, I just turn up the pressure to 20-30 psi and put a picnic tap on the outlet and 90% of the time the beer flows. Sometimes it still doesn't flow, so I will connect it and disconnect the tap quickly if it's really stubborn. I have never needed to open up the fermenter to unclog a line.
 
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I would look into this if it didn’t add to the complication of cleaning kegs, which I like about as much as emergency dental work.
 
Once the beer is cold I really don’t think you will get off flavors from the yeast cake. I’ve done this with lagers and 3470 yeast many times with no issues that I could taste. I also drank the beer within a month. Also if you are doing this in a corny keg your batch will probably be slightly smaller and thus not last as long. I really like brewing this way.
 
I usually leave my keg fermented beer on the yeast, and serve through a Flotit dip tube, unless I'm using lots of hops or adjuncts. I usually finish it off within two months, with no off flavors.
 
Do you rack off the trub in the keg?
 
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