Fermenting in keg - Is fermcap necessary?

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BrewdyQuah

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I'm going to attempt to ferment in a keg, then transfer to another and finish it off under pressure (spund). I'll probably use the spunding valve on the FK but with only 2-3 PSI (instead of a blow off).

I'll be doing a 5 gallon batch of IPA. Since I know krausen build up can inadvertently block the small gas port on a keg, I've seen recommendations for increasing headspace to reduce this risk. I have bought a 6 gallon torpedo keg so that I have more headspace than trying to use a 5 gallon keg.

If I am putting 5 gallons of wort in the 6 gallon keg, do I still need to add fermcap-s to control the foam/krausen? I'm just hesitant on adding more things that can alter the taste, but also don't want to risk building a pressure bomb.

Thanks!
 

odie

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I've done several ferments in a keg recently. I do a full 5 gal of wort in a 5 gal keg (up the to weld line). That leaves slightly more than 1/2 gal headspace. no fermcap and no issues with krausen blowing out...unless it's a hefe.

I completely remove the gas post and fit a blow off tube. After fermentation slows I'll reinstall the gas QD and spund to finish and carb.
 

Curtis Shaw

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I've fermented 19 liters in 20.5 liter (5 gallon) corny kegs without a problem but I remove the gas popit from the keg and disconnect for the first 3 days. I run a blow off tube from the disconnect to a jar of Starsan.

I think some yeasts are more prone to eruptions than others. I try to keep fermentation temperatures on the low side to keep them behaving. WLP 090 and WLP 200 work fine. I'm going to try WLP 300 next, we'll see.

I haven't had to use Ferm Cap yet but wouldn't hesitate if things got crazy.

I've been real happy with corny kegs as fermenters. Have fun!
 

marc1

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I'm going to attempt to ferment in a keg, then transfer to another and finish it off under pressure (spund). I'll probably use the spunding valve on the FK but with only 2-3 PSI (instead of a blow off).

I'll be doing a 5 gallon batch of IPA. Since I know krausen build up can inadvertently block the small gas port on a keg, I've seen recommendations for increasing headspace to reduce this risk. I have bought a 6 gallon torpedo keg so that I have more headspace than trying to use a 5 gallon keg.

If I am putting 5 gallons of wort in the 6 gallon keg, do I still need to add fermcap-s to control the foam/krausen? I'm just hesitant on adding more things that can alter the taste, but also don't want to risk building a pressure bomb.

Thanks!

A few drops of fermcap is cheap insurance.

I recommend jumping the gas post on your fermenting keg to the liquid post on your spunding/serving keg. Then put your spunding valve on that keg.

That way if something does foam out of the keg, it isn't messing up your spunding valve. Also, your serving keg gets purged of O2 with no extra work.
 
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