Pressure fermentation in the same keg that the beer gets served from.

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Elysium82

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I am reading the info on this website: Under Pressure:Fermentation in a closed system.

How is this even possible? It says this:

  • Pressure fermentation can streamline your process:many homebrewers ferment their beer in the same keg they’ll drink it from. By fermenting in a corny keg, or a sanke, you no longer need to spend time transferring to other vessels.

How come the sediment from fermentation can stay in the same keg? Doesn't it get all disturb and end up in your final product?
Am I missing a key point here? Maybe cold crushing?

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twd000

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I have all my kegs fitted with a floating dip tube with a mesh intake filter. Sludge on the bottom, clear beer on top, all the way down
 

CascadesBrewer

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A thread on the topic: have you tried fermenting and serving from the same keg without transferring?

I am currently drinking my first beer fermented and served from the same keg. I am using a floating dip tube (a FLOTit). I am not 100% sold it is my future, but it has been an easy process and the beer is fine. Next I will try fermenting in a keg and transferring to a serving keg.
 
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Elysium82

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A thread on the topic: have you tried fermenting and serving from the same keg without transferring?

I am currently drinking my first beer fermented and served from the same keg. I am using a floating dip tube (a FLOTit). I am not 100% sold it is my future, but it has been an easy process and the beer is fine. Next I will try fermenting in a keg and transferring to a serving keg.
Thank you. What makes you transfer? Does it taste different then what it used to? Too much turb? I am just guessing. :D
 

twd000

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Ah, perfect. I assume it is something like this: Corny Keg Floating Dip Tube | Craft Hardware

Sounds great. So, do you just swear by this "pressure fermantation"?

similar, but mine have a wine filter screen on the intake to prevent dry hops from clogging the keg poppet: 10X Stainless Steel Mesh Homebrew Inching Siphon Filter Brew Beer Wine Making | eBay

pressure fermentation and uni-tank-style ferment-and-serve are two separate but related processes

for ales, I don't aply and top pressure during fermentation - I just spund to 30 psi about 48 hrs in to fermentation to catch the residual CO2
for lagers, I sometimes apply 15 psi top pressure during fermentation, depending on temperature

I have used the ferment-and-serve process for all my beers the last 2 years. Probably 20 batches. I'm happy with it. I may start transferring some lagers to a serving keg if I expect they will be lagered for more than ~ 2 months.
 

william_shakes_beer

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You do You. I always transfer from fermenter to keg simply to remove trub from the packaged product. I understand floating dip tubes draw from the surface, whereas trub settles t the bottom. That works fine so long as the keg is not disturbed.
 

CascadesBrewer

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Thank you. What makes you transfer? Does it taste different then what it used to? Too much turb? I am just guessing. :D
This is my first try at keg fermenting, so I have not tried transferring. The beer is pouring as clear as I would expect and I don't notice any off flavors, flaws or issues that I can see from serving from the fermenting keg. The beer was brewed April 1, so it is only 18 days old today.

The fast turn around is a big appeal to me. I brew a lot of small batch investigative type batches (to evaluate hops, grains etc.). The typical 4+ week cycle to ferment and bottle condition is a pain. I could potentially keg ferment with a spunding valve using a clean Kveik yeast and be evaluating the beer 1 week from brew day.

Picture of my 18 day old Pale Ale that I just snapped (fermented with Voss, not dry hopped).

IMG_3125.png
 

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How long can the keg sit before you tap it? I usually keep several kegs of finished beer in storage, waiting for a tap to open up. Some beers sit for over a year (RIS, Quads). but most sit a few weeks to a few months.
 

EDF713

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I do this, I ferment in a tall pinlock corny (~5.25 gal keg) under pressure with a spunding valve, and transfer to a CO2 purged serving keg via closed transfer (pic). It's super easy. Under pressure is great because it pushes the krausen down and I can get a 5 gallon batch out of this. Word is that esters may be suppressed, but I'm usually going for cleaner styles and don't care.

I like to transfer to a serving keg since my floating dip tube can kick up a little sediment towards the end of the keg. I think part of the tube brushes the trub at some point, especially with a more powdery yeast like W34/70 or kolsch.
 

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Brews and Blues

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I am interested in this method to save myself some time cleaning equipment and siphons. Is a spunding valve necessary to ferment in a corny? Or can it be done without?
 

twd000

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I am interested in this method to save myself some time cleaning equipment and siphons. Is a spunding valve necessary to ferment in a corny? Or can it be done without?

you could do it without a spunding valve, but you'd want to rig up an airlock at least. Otherwise you're rolling the dice with sealing the keg too early (over-pressure) or too late (oxygen ingress).

In my opinion, a BlowTie spunding valve is $15 well spent if you keg your beers. Makes it so easy to monitor and adjust pressure in various kegs as they condition, blowoff excess pressure if you need to, etc.
 

EDF713

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you could do it without a spunding valve, but you'd want to rig up an airlock at least. Otherwise you're rolling the dice with sealing the keg too early (over-pressure) or too late (oxygen ingress).

In my opinion, a BlowTie spunding valve is $15 well spent if you keg your beers. Makes it so easy to monitor and adjust pressure in various kegs as they condition, blowoff excess pressure if you need to, etc.
I agree. I've used a piece of vinyl tubing connected to a gas disconnect for blow-off, if you did this I'd recommend 4.5 gallon batches for headspace in a 5 gallon keg. Depending on the beer and yeast, you could also get a lot of gunk inside on the top of the keg, fermenting under pressure lessens this since the pressure pushes the krausen down and it falls into the trub. Dry hopping can be tricky, but If I plan to dry hop I start in a carboy then transfer to the keg as fermentation starts slowing.

I'm a big fan of spunding. The valve doesn't cost much, you can pressure ferment if you want, and you can naturally carbonate your beer for faster turnaround without worrying about over carbing.
 

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CascadesBrewer

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The beer is pouring as clear as I would expect and I don't notice any off flavors, flaws or issues that I can see from serving from the fermenting keg.
While not an issue strictly due to fermenting and serving from the same keg, my keg has started to pour lots of foam. I am using a FLOTit floating dip tube that I got off eBay. It seems like a well designed device with positive reviews. I just weighed the keg and it has about 0.5 gals of beer in it. I assume the float is tilted and the pickup tube is at surface level.
 

renstyle

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I have all my kegs fitted with a floating dip tube with a mesh intake filter. Sludge on the bottom, clear beer on top, all the way down
I use this same floating dip tube + mesh filter in my ferm keg. Crash to let the big bits floc out, then gelatin fine.

While I usually transfer to a serving keg closed xfer, I could easily leave it all in there.

I just choose to cycle my ferm keg to a new batch. She rarely spends much time outta the chamber that way! :D
 

Brews and Blues

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Alright guys, i have a spunding valve and floating dip tube with filter on its way. I also bought and inkbird and a chest freezer for temp control. I am really interested in fermentation in the serving keg just to save from cleaning and siphoning. So my next brew is a black IPA kit using US-05 and I need to dry hop. So let me run down my plan here:

After brewing and cooling, pour wort into sanitized keg, top off to 5 gallons, pitch yeast, stir well.
Seal keg, add spunding valve to line out post ??? And then ferment for 7 days in temp controlled freezer from 62-65 degrees, release CO2 that built up, open keg and add hop pellets for dry hop, reseal. After fermentation is complete, move keg to kegerator, add CO2 to desired PSI, and once fully carbed - drink.

Do you guys see any issue with this? My main questions are:
1 - what post to put the spunding valve on
2 - do you see any issues with dry hopping with this method
3 - does my temp range look okay, and
4 - there aren't any issues with the beer sitting on the yeast and trub for extended time? side note: i tend to drink a 5 gallon batch in about 5 weeks if you need a time frame.
 

twd000

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Alright guys, i have a spunding valve and floating dip tube with filter on its way. I also bought and inkbird and a chest freezer for temp control. I am really interested in fermentation in the serving keg just to save from cleaning and siphoning. So my next brew is a black IPA kit using US-05 and I need to dry hop. So let me run down my plan here:

After brewing and cooling, pour wort into sanitized keg, top off to 5 gallons, pitch yeast, stir well.
Seal keg, add spunding valve to line out post ??? And then ferment for 7 days in temp controlled freezer from 62-65 degrees, release CO2 that built up, open keg and add hop pellets for dry hop, reseal. After fermentation is complete, move keg to kegerator, add CO2 to desired PSI, and once fully carbed - drink.

Do you guys see any issue with this? My main questions are:
1 - what post to put the spunding valve on
2 - do you see any issues with dry hopping with this method
3 - does my temp range look okay, and
4 - there aren't any issues with the beer sitting on the yeast and trub for extended time? side note: i tend to drink a 5 gallon batch in about 5 weeks if you need a time frame.
put the spunding valve on the gas post. If you put it on the liquid post, the pressure will push beer out of the keg and onto the floor

otherwise plan looks good
 

EDF713

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sounds good. I like to put about 5 psi of pressure from my CO2tank before adding the spunding valve to make sure the lid is sealed well. I don't see mention of what pressure you plan to ferment at. I'd keep it at 5-15 if you're going to dry hop, like ThenFalcon says, you could get a mess if you release too quickly then add the dry hops. Remember, the beer is holding CO2, not just the headspance. Adding dry hop pellets to carbonated beer isn't quite mentos in diet coke, but still could be messy.
 

Brews and Blues

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sounds good. I like to put about 5 psi of pressure from my CO2tank before adding the spunding valve to make sure the lid is sealed well. I don't see mention of what pressure you plan to ferment at. I'd keep it at 5-15 if you're going to dry hop, like ThenFalcon says, you could get a mess if you release too quickly then add the dry hops. Remember, the beer is holding CO2, not just the headspance. Adding dry hop pellets to carbonated beer isn't quite mentos in diet coke, but still could be messy.
Awesome thanks! My next question was going to be fermentation PSI because my spunding valve can be calibrated to the desired level.
I'm pretty excited about this. Between this and controlling fermentation temps, I feel like I am starting to up my game a bit. My goal is to make better beer but do it with less overall equipment. My least favorite part of brewing is by far the cleaning and anything to do with the siphon - mostly because then i have to clean the damn siphon and tubing 😂
 

EDF713

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Awesome thanks! My next question was going to be fermentation PSI because my spunding valve can be calibrated to the desired level.
I'm pretty excited about this. Between this and controlling fermentation temps, I feel like I am starting to up my game a bit. My goal is to make better beer but do it with less overall equipment. My least favorite part of brewing is by far the cleaning and anything to do with the siphon - mostly because then i have to clean the damn siphon and tubing 😂
Cool! Let us know how it turns out. The YouTube channel for the video ThenDragon linked to has some good examples. I hear you on the siphon, the big plus is your beer has less oxygen exposure.
 

renstyle

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So let me run down my plan here:
Quick response to main questions:
1. spund goes on the gas post always.
2. since you're picking up a mesh filter which attaches to the floating dip tube, looks good!
3. temp range looks OK for an ale
4. no real worries keeping the beer on the yeast cake all the way thru to keg-kick. 6-8 weeks all in should be just fine.

Be aware that there is approximately 5.3 gallons of volume inside a standard corny keg. You may wish to leave more headspace than 0.3 for fermenting.

I use fermcap, few drops (2-3) before I pitch the yeast when keg fermenting. I've maxed my volume to maybe 4.8 gallons, and still get a little blow-off from time to time.

The pressure you wish to dial in will help with this somewhat. Higher spund PSI, say 10+ will more markedly hold down the krausen than at 1 atm non pressure.

You could also opt to run a regular blow-off tube for the first 1-3 days, get the vigorous activity past, then start spunding for the rest of the fermentation. This is the route I would suggest. ;)

For the spunding valve on that gas post, I'd recommend a bit of extra line should you get some beer/krausen/etc into that line. If it hits the spunding valve it'll be a PITA to clean at minimum, and may break the valve. If possible, keep the spunding valve ABOVE the keg to get a slight gravity assist. 😎

The only part I cannot give a good response to is whether to spund BEFORE dry hopping or only afterwards. Pre-carbing then dropping a bag of pellets (or whatever you choose) could cause off-gassing and an overflow if you don't latch the lid fast after the drop!

I always dry hop with a few gravity points left to go, so there will be more fermentation post-dry hop charge. With this in mind I do the dry hop addition a bit sooner, and delay spunding until after the keg is re-sealed.
 

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@cascades
While not an issue strictly due to fermenting and serving from the same keg, my keg has started to pour lots of foam. I am using a FLOTit floating dip tube that I got off eBay. It seems like a well designed device with positive reviews. I just weighed the keg and it has about 0.5 gals of beer in it. I assume the float is tilted and the pickup tube is at surface level.
It's worth putting a stainless steel nut on the silicone dip tube. The extra weight helps to pull the tube down and the intake below the surface. Also make sure tube is not much longer than length to the bottom of the keg. I had real problems with this using fermentasaurus mark III without a filter and the inlet kept getting trapped inside the little ring that the float was attached to.
 

renstyle

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I had tried doing the nut route for a few brews, then I found this:


I attached my SS float-ball to the eyelet furthest away from the barb, and it does a pretty decent job keeping the line under the surface.
 

CascadesBrewer

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It's worth putting a stainless steel nut on the silicone dip tube. The extra weight helps to pull the tube down and the intake below the surface. Also make sure tube is not much longer than length to the bottom of the keg. I had real problems with this using fermentasaurus mark III without a filter and the inlet kept getting trapped inside the little ring that the float was attached to.
I emptied the keg the other day and snapped a picture. At this point, any trub/yeast had gotten stirred up a bit. It was pouring very clear until I started to get foam. Maybe a little longer length of hose or a weight would get a little more beer, but I doubt much. I measured right around 1/2 gallon of beer/trub/yeast liquid.

Overall, I was pretty happy with the results of my first time fermenting in a keg. I am also very happy fermenting in my Fermonster fermenters, but I will play around more with keg fermenting.

floating dip tube in keg.png
 

DuncB

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Ahh I see a slightly different arrangement for the float and tube with your setup.
Weight on tube and a bit more length might help there. Or a ring to link the float to the tube as per the kegland keg king type floats and a nut.
 

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I was happy with the Clear Beer Draught System which always sets below the liquid line and has a filter. I have not tried it with dry hops in the keg but they claim it's a great way to do so. If I ferment in the keg I'll use it for sure.
20190125_180443.jpg
 

Brews and Blues

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You could also opt to run a regular blow-off tube for the first 1-3 days, get the vigorous activity past, then start spunding for the rest of the fermentation. This is the route I would suggest. ;)
For a blow off tube, would you do just a ball lock connector with tubing coming off of the gas post into a bucket of water? I may go this route just so i don't create a mess
 

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For a blow off tube, would you do just a ball lock connector with tubing coming off of the gas post into a bucket of water? I may go this route just so i don't create a mess
After I pitch yeast, I don't put a gas post onto the keg right away. I put a 1/2" silicone tube directly into the keg opening, then into a growler with water on the bottom. It makes for easier cleanup, instead of having to clean out the gas post and ball lock connector.
 

renstyle

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After I pitch yeast, I don't put a gas post onto the keg right away. I put a 1/2" silicone tube directly into the keg opening, then into a growler with water on the bottom. It makes for easier cleanup, instead of having to clean out the gas post and ball lock connector.
Good point on the cleanup. Do you unscrew the gas post for the first few days to attach the 1/2" silicone tube? Or perhaps the PRV hole with the PRV set aside?

So far for me, a little starSan spray to clear potential gunk in the gas QD and the exterior of the post has worked reasonably well.

I've been using one of these:


...with a short length of EVA barrier attached inside a PET soda bottle to clean the gas tube once the keg has kicked (or transferred to serving, as you like), as you can pressurize the bottle or just fill-n-squeeze. :)

Since I generally xfer from ferm-keg to serv-keg, I haven't had issues with the gas poppet getting stuck. Using the keg as ferm+serv combo tho, I can see the benefit of keeping the gas post mostly clear of funk.
 

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For a blow off tube, would you do just a ball lock connector with tubing coming off of the gas post into a bucket of water? I may go this route just so i don't create a mess
I started with a growler 1/2 full of starSan solution as the blowoff vessel, and dealt with excess bubbling (suds) which topped my growler a few times when the fermentation was particularly vigorous.

I am certain that my choice of using an extra length of 4mm EVA Barrier, which makes more/smaller bubbles added to this (was like a mini beer-scented washer from a sitcom LOL).

I opted to keep the 4mm line and switch to using vodka in the blow-off growler, as I had some available, so far so good. starSan solution in the blow-off vessel should be fine with a larger diameter line tho.
 

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After I pitch yeast, I don't put a gas post onto the keg right away. I put a 1/2" silicone tube directly into the keg opening, then into a growler with water on the bottom. It makes for easier cleanup, instead of having to clean out the gas post and ball lock connector.
So 1/2 silicone hose will fit over the threaded gas post on the keg? You just have the fitting, poppet and dip tube removed?
 

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Using the kegland T piece you can dump into the first ( I use a small pet bottle 250ml ) and then Blow off tube from the other port into the under water valve in the growler. No pressure on the system this way for good expression and really easy top harvest of yeast.
 
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