Fermenting in Kegs - 1st time

[Ragman]

Planning on fermenting in my kegs for this next batch - would love to get away from carboys.

Im planniing out my brew day and I have a couple questions.

After I transfer my wort to the keg and pitch my yeast, do I add any co2 to it or just throw the centercap on and the blowoff? (gas disconnect connected to tub running into bucket of star san)

Im making an DDH NEIPA and I think I have a couple choices for ferm temp. I normally just put the FV in my basement which for the most part maintains a 68-70 degree range - but it can fluctuate.

I thought about turning the temp up on my inkbird and using my keezer as an FV to keep the wort at a more stable temp. I would have to bring it back down when I was ready to transfer to my serving kegs for carbonation tho.

thoughts?

 

[odie]

just cap it and put a tube on. I suggest removing the poppet or entire disconnect until the ferm slows. Or ditch the tube and spund/pressure ferment from the start.

 

[minorhero]

I am fermenting in a keg for my first time right now. I decided to go pressure ferment. If you are not doing a pressure ferment then there is no advantage in using a keg over a cleaned carboy other then there being less chance of light interacting with your beer in a keg and its easier to move a keg.

For my pressure ferment I filled the keg up with wort, pitched my yeast, sealed the keg, and immediately added 5 psi of co2. Then attached my spunding valve. This way I don't get krausen forming and mucking up my spunding valve. I am using an ispendel to track when fermentation is complete. Good luck!

 

[Knightshade]

I did 4G in a 5G keg of cider a couple of weeks ago with S-04. Blow off definitely got a little mucky. I've read that some people utilize Fermcap to help keep Krausen from getting too out of control? My next batch I'll be using a 6G keg, wanting to move away from plastic fermenters because I'm consistently paranoid about scrubbing to hard to scratch the plastic, but not getting them clean enough. Had a recent batch go bad so that seems like as good a place to start as any?

 

[Gnomebrewer]

I am fermenting in a keg for my first time right now. I decided to go pressure ferment. If you are not doing a pressure ferment then there is no advantage in using a keg over a cleaned carboy other then there being less chance of light interacting with your beer in a keg and its easier to move a keg.

For my pressure ferment I filled the keg up with wort, pitched my yeast, sealed the keg, and immediately added 5 psi of co2. Then attached my spunding valve. This way I don't get krausen forming and mucking up my spunding valve. I am using an ispendel to track when fermentation is complete. Good luck!

The problem with pressure fermenting from the start is that you'll have a much slower ferment, unless your ferment is much warmer than normal (which is a valid route to take). Also, dryhopping an already carbonated (pressure fermented) beer is difficult; assuming the ferment is at 25 to 30psi at room temp, you end up with a volcano if you try to take the lid off. I've tried pressure fermenting from the start, but I think other methods are better.

Fermenting in kegs is still very worthwhile compared with a standard (non pressurised) fermenter. You can spund towards the end of fermentation (after four or so days of using a blowoff tube or similar) along with a temperature increase. Also, it allows proper closed transfers such that fermented beer never sees air. My preferred method is to ferment to about four to six points from completion, then pressure transfer to purged serving kegs and spund in serving kegs. If you did this from a non pressure fermenter, you'd be drawing air on top of the beer being transferred (although the difference is probably only marginal).

 

[minorhero]

The problem with pressure fermenting from the start is that you'll have a much slower ferment, unless your ferment is much warmer than normal (which is a valid route to take). Also, dryhopping an already carbonated (pressure fermented) beer is difficult; assuming the ferment is at 25 to 30psi at room temp, you end up with a volcano if you try to take the lid off. I've tried pressure fermenting from the start, but I think other methods are better.

Fermenting in kegs is still very worthwhile compared with a standard (non pressurised) fermenter. You can spund towards the end of fermentation (after four or so days of using a blowoff tube or similar) along with a temperature increase. Also, it allows proper closed transfers such that fermented beer never sees air. My preferred method is to ferment to about four to six points from completion, then pressure transfer to purged serving kegs and spund in serving kegs. If you did this from a non pressure fermenter, you'd be drawing air on top of the beer being transferred (although the difference is probably only marginal).

My fermentation does not appear to be slower. Based on the graph from the ispindel fermentation should be done sometime tonight, but I won't transfer till tomorrow morning (2.5 days since the kettle). Temperatures in my unfinished basement have been in the mid 70s. The beer has been between 85 to ambient depending on when in the fermentation we are talking about. PSI has been kept at 14. I did some reading before brewing and decided to overpitch. Based on other people's experiences the best thing about pressure fermentation is temperature control is not an issue, you can get good results without a fermentation chamber. BUT other then what I am seeing with the ispindel all of this is based on other people's experiences since this is my first pressure ferment.

 

[DuncB]

Just remember that your ispindel reading will be off unless you calibrated it under pressure as well. But it shows the trend beautifully.
I agree pressure ferment a little warmer low pressure on spunding to start and then build up to your final vols pressure over the last 10 gravity points or so.
I did invest in some nitrile o rings for the tops of my ispindels as I had a few leak under high pressure. Sure sign of this is when you see attenuation higher and gravity lower than you would expect. Stout recently with kveik said at 0.999 but when transferred found about 1/4 inch of wort / beer in it.
It was still working and works okay after a good clean and dry.

Previously I sank an Ispindel and that remarkably worked fine again after a really good clean and dry. It was half full of NEIPA!!

 

[minorhero]

Just remember that your ispindel reading will be off unless you calibrated it under pressure as well. But it shows the trend beautifully.
I agree pressure ferment a little warmer low pressure on spunding to start and then build up to your final vols pressure over the last 10 gravity points or so.
I did invest in some nitrile o rings for the tops of my ispindels as I had a few leak under high pressure. Sure sign of this is when you see attenuation higher and gravity lower than you would expect. Stout recently with kveik said at 0.999 but when transferred found about 1/4 inch of wort / beer in it.
It was still working and works okay after a good clean and dry.

Previously I sank an Ispindel and that remarkably worked fine again after a really good clean and dry. It was half full of NEIPA!!

GAH! I didn't even consider the thing leaking. Do you by chance have a link to the O rings you purchased? My Ispindel is fantastically uncalibrated so the numbers it displays are essentially nonsense, its just the trend I am following and for my purposes that's fine. For an accurate FG I'll take a sample by attaching a tap directly to the keg. The ispindel is more for telling me when to go ahead and do that.

 

[DuncB]

GAH! I didn't even consider the thing leaking. Do you by chance have a link to the O rings you purchased? My Ispindel is fantastically uncalibrated so the numbers it displays are essentially nonsense, its just the trend I am following and for my purposes that's fine. For an accurate FG I'll take a sample by attaching a tap directly to the keg. The ispindel is more for telling me when to go ahead and do that.

These are the ones I bought
https://www.aliexpress.com/item/32862998881.html?spm=a2g0s.9042311.0.0.27424c4dVyqyKgI have done a couple of pressure ferments with these in and been ok. If china wasn't closer I'd send you some spares but they'll come quicker from china or be sourced by you locally faster I'm sure.

I think that really hot ferment and high pressure more of an issue than cool and pressure. But it's good insurance.
THe idea came from this website
https://www.diyhomebrewers.com/
but I cannot find the exact page on it that detailed the oring. Google translate not working too well.

 

[minorhero]

These are the ones I bought
https://www.aliexpress.com/item/32862998881.html?spm=a2g0s.9042311.0.0.27424c4dVyqyKgI have done a couple of pressure ferments with these in and been ok. If china wasn't closer I'd send you some spares but they'll come quicker from china or be sourced by you locally faster I'm sure.

I think that really hot ferment and high pressure more of an issue than cool and pressure. But it's good insurance.
THe idea came from this website
https://www.diyhomebrewers.com/
but I cannot find the exact page on it that detailed the oring. Google translate not working too well.

Thank you this will be a big help!

Edit: Found these on amazon which appear to be the right stuff for anyone else in the same boat.

 

[Ragman]

Thanks for the replies everyone. I dont have a spunding valve so I dont think I will be pressure fermenting. I am double dry hopping and it seems it would be difficult to add hops not only once but twice during fermentation.
So I think I will just add wort, pitch yeast, cover and attach blowoff then put in the basement where it usually stays about 68-70 degrees. After 8-10 days I will release the pressure, drop in my sanitized hop bag with a stainless weight all attached with satin floss and put the lid back on.
Should I attach the CO2 and purge after I have opened the lid to add the hops? Just to be sure there isnt any O2?

If so I plan to repeat this process at day 12-14 with the hops and transfer to serving keg on day 16.

 

[Gnomebrewer]

My fermentation does not appear to be slower.

No, you've offset the pressure by increasing temperatures. That is the advantage of the pressure ferment - reducing esters when you can't control temperature. Also be aware that 14PSI won't be anywhere near fully carbonated, so raise the pressure towards the end of the ferment or be prepared to finish carbonation with bottled CO2.

I'm interested to hear what you think of the finished beer. I don't think pressure fermenting is a magic bullet for high temperatures, but it definitely does subdue some off flavours. I tried a couple of pressure ferments (at increased temps) and found them a bit meh....certainly not bad but a bit undefined or flat (it's hard to describe); I really like esters and yeast complexity though, so YMMV. Which yeast strain are you using?

 

[Spundit]

After I transfer my wort to the keg and pitch my yeast, do I add any co2 to it or just throw the centercap on and the blowoff? (gas disconnect connected to tub running into bucket of star san)

I primarily ferment in a 5g ball lock keg. A blow off tube as you described works fine. I do not add CO2 to the keg to pressurize and seal it and I have not had any problems. However, some lids just don't seal without pressure. You can use a little keg lube on the lid gasket if you want a little extra insurance.

My normal batch size is 4.5 gallons into the fermenter. Sometimes I get some blow off into the tube. A smaller batch size would be safer if this concerns you.

After 8-10 days I will release the pressure, drop in my sanitized hop bag with a stainless weight all attached with satin floss and put the lid back on.
Should I attach the CO2 and purge after I have opened the lid to add the hops? Just to be sure there isnt any O2?

Purging with CO2 should not hurt anything and should help minimize oxidation.

Do you plan to do a closed transfer to your serving keg at the end? That is another great way to minimize oxidation.. It is pretty easy to do when fermenting in a keg.

 

[minorhero]

No, you've offset the pressure by increasing temperatures. That is the advantage of the pressure ferment - reducing esters when you can't control temperature. Also be aware that 14PSI won't be anywhere near fully carbonated, so raise the pressure towards the end of the ferment or be prepared to finish carbonation with bottled CO2.

I'm interested to hear what you think of the finished beer. I don't think pressure fermenting is a magic bullet for high temperatures, but it definitely does subdue some off flavours. I tried a couple of pressure ferments (at increased temps) and found them a bit meh....certainly not bad but a bit undefined or flat (it's hard to describe); I really like esters and yeast complexity though, so YMMV. Which yeast strain are you using?

I actually decided to pressure ferment as a means of temperature control or rather a way of not needing to invest in a fermentation chamber or chiller. A spunding valve is a lot cheaper than another refrigerator for instance.

Anyway I am also interested to see how pressure fermentation handles things like over pitching yeast and cold crashing as soon as fermentation is complete (as opposed to waiting a few extra days) by way of preserving an ales character. /Shrug it's my first time doing it so I have lots of ideas and questions but short on experience.

I tasted a sample shortly after fermentation finished up this morning and it definitely tasted young heh. There was nothing horrific with it though, it just needs a few days to mellow out. I added a mini regulator and CO2 cartridge, set it to 8 or so psi and let it do it's thing.

Yeast is yeast 1056.

 

[WesBrew]

I ferment in a keg sometimes and Just use a spunding valve set around 3-4 psi. it works great. Also cool is doing the closed transfer with a floating diptube. I do not pressure ferment but hear you can get away with higher fermentation temps