How to purge kegs with CO2 from pressure fermentation

[@davec4955]

Once you finished purging the starsan you could pop the spunding valve onto the corny keg to equalise the pressure with the fermzilla, ready for a closed transfer !

[@imperia1999]

Nice little trick on saving some C02 , thanks for sharing .

[@TheMattMustain]

Great idea! I'd like to try this. Any off odd flavors or aromas collecting CO2 this way? What if collecting in a chained second keg to use later for a different style of beer?

[@ElementaryBrewingCo]

Can you set this up without the spunding valve? Would it work just the same except there’s no pressure built up in fermenter?

[@DudesBrews]

It would work without the spunding valve yeah, I'm not sure exactly what would happen with the pressure levels over time though there has to be some head pressure in the FV in order to start pushing out the sanitiser, might depend on how vigorous the ferment is as well

[@jasonclick]

great video Dude! Thanks for putting it together.

[@bradvonreaden1550]

Good video. Doing the same thing now but without the sounding valve. Question though. The dip tube in the 2nd keg is also cut back so there is no way to evacuate all of the starsans prior to transferring. How do you overcome this issue, or is it not an issue at all to have that remaining starsans mix with the beer?

[@lordxraven12]

First of all: Thanks for sharing, I like this approach. This is already two years old but maybe I'm lucky and still get an answer: When pushing the starsan-liquid out of the keg, after it has finished and only CO2 is escaping anymore into the bucket, can you tell how much is still left in there? I assume that little amount will stay back?! Is it in any way a problem or is it so little, that it doesn't matter at all?

[@DudesBrews]

Thanks there will always be a small amount left in the bottom of the keg, it causes no issues at all

[@Justgoogleit24]

Going to copy this, super smart!

[@MrFastfreddie19]

Great video

[@andyb8797]

Any chance you can do a quick video of your setup. Keen to see how you ferment

[@DudesBrews]

what do you want to know exactly?

[@andyb8797]

can see you have a fermzilla, is it a 27 or 55 version? For the speidel fermenter, can you let me know the size? If you have both in use, do you just ferment at one temp? Looking to get a tall fridge, what width do you need for a fermzilla? Also keen to know your brewing setup if you can give any details? Tks AB

[@DudesBrews]

this is the fermzilla plus pressure kit v2, dimensions are on one of the pics www.angelhomebrew.co.uk/fermzilla/486-30l-fermzilla-all-rounder.html this is the speidel www.brewuk.co.uk/speidel-30l-fermentor.html if I have 2 batches in at once I try to do stuff that needs the same sort of temp to start with and I will if they don't go in at the same time the probe goes on the most recent batch i.e. the one actively fermenting. I use an SS brewtech kettle with a buffalo induction hob, also have 55L stainless kettle that I use as HLT, mash in a homemade bucket tun. So 3 vessel brewing essentially

[@andyb8797]

@@DudesBrews Super, great setup!

[@ConnerKisiel]

Would sending the beer into the "in" cause any off-flavors to produce as it splashes down into the keg? Normally I would fill the keg with CO2, open the seal, run a line down to the bottom of the keg, drain my fermenter, then cap off the keg, and purge multiple times before force carbonating (rolling over legs, etc.)

[@Nigellittle12]

Awesome idea! How far into the brew did you do this? Presumably the keg is then fine (sanitised and purged) until you have finished fermenting and cold crashing? Do you then have uncarbonated beer which you have to force carb in the keg?

[@DudesBrews]

I wait until a krausen is established and fermentation is properly started personally, yeah the keg is then fine to leave until transfer. You can still partially carb the beer in the FV under its own pressure but it will normally need a little top up from the gas bottle to get it right

[@Nigellittle12]

@@DudesBrews awesome. Thanks for reply 👍 can you remember how much gas you used to top up? Its dear these days so trying to save as much as I can lol

[@DudesBrews]

@@Nigellittle12 no idea tbh, would depend on how high you set the pressure on the FV spunding valve (can crank this up towards end) and how high a co2 volume you are aiming for at the end. It is possible to fully naturally carbonate using the pressure FVs if you get the final pressure and cold crash right if you really want to maximise the co2 harvest!

[@finnroohomebrewing]

Cheers Dude, great video.😎👍

[@DudesBrews]

Thanks 👍

[@TheJoshGable]

have you ever put two kegs in series that are connected to the blow off?

[@DudesBrews]

No but no reason that wouldn’t work, you could chain several together and do them all at once I imagine

[@ChrisKirtley]

Could you store the CO2 for serving? I like the idea of natural carbonation (and don't want to buy CO2!), but this would provide additional pressure to get the last few litres out. Or is the pressure in the keg too low for that?

[@DudesBrews]

Theoretically yes, you'd not get much out before the pressure dropped

[@DinakarJayarajan]

Great idea! What is the minimum pressure needed in the fermenter to have the Starsan forced out of the keg?

[@timmyG]

I just did it with a grainfather conical fermenter which is limited to 1.5 PSI. It's slow though :)

[@andyclark6012]

Great idea 👍 did you ever do that video for the soma/Sonoma clone pale? I've done a few clones similar, be interested to see that one!

[@DudesBrews]

Coming soon! Its on tap as you may have spotted and the video is in production...

[@dutch2975]

Super idea thank for sharing that 🍻👌

[@fishingaddictionnz3656]

What psi on spunding valve do you use when doing this

[@DudesBrews]

Fishing Addiction NZ it was set to 15 in this case but I don’t think it’s that important what pressure it’s at tbh

[@p.chuckmoralesesquire3965]

Once you purge the keg with c02 how do you transfer to it?

[@p.chuckmoralesesquire3965]

Or does that not really matter? just transfer as normal with gravity or racking cane ?

[@DudesBrews]

I do a closed transfer under gravity, like this: kzbin.info/www/bejne/paenZ2Cuh7qHr6s

[@p.chuckmoralesesquire3965]

@@DudesBrews thanks for the link! been wanting to do pressure fermentation for a while now

[@BoeinBrews]

Found his helpful as just bought a chubby fermenter. Cheers 🍺👍🏻

[@BrewabitRick]

Nice work I like it I like it a lot cheers informative vid 🍻👍

[@acdmonteiro]

Why not just mix the starsan in the keg first?

[@MrVinylNinja]

Great idea

[@DudesBrews]

Thank you! Cheers!

[@MrVinylNinja]

@@DudesBrews done this yesterday, didn't have a spunding valve so just pushed full keg of starsan to another keg.

[@Dts1953]

Top idea👍👍👍

[@DudesBrews]

Thank you! Cheers!

[@discostucrazymunkey]

Why not go fermzilla-gas to the keg-liquid then keg-gas to blowtie. It will store the gas, save the aroma (bonus for ipa). Plus it ensures positive pressure of CO2.

[@HeartPumper]

With starsan in keg?

[@discostucrazymunkey]

@@HeartPumper once it has been sanitised and has a positive pressure of CO2 it will be fine to leave. I sanitise, rinse then hook up. No problems yet.

[@benjaminlebens2260]

This won't work. There is no positive pressure on the keg lid to keep it sealed. You need to add an additional keg in the chain and move your spunding valve to the end of that keg.

[@DudesBrews]

Done this many many times and it absolutely works, of course you have positive pressure if the lid never sealed it would make no difference having a spunding valve on a final keg either, although doing it that way would mean you can have the keg automatically equalised with the FV which would be beneficial for the transfer later

[@benjaminlebens2260]

@DudesBrews Gently push down on the keg lid next time your syphon is running.

[@DudesBrews]

@@benjaminlebens2260 its positive pressure pushing the starsan out of the keg, if the lid wasn't holding a seal then the flow of liquid would never start and its not a syphon action because the keg dip tube runs to the bottom of the cylinder, admittedly the lids can take a bit of fiddling with to get the o ring to sit properly but as I said if they weren't then the liquid would never get pushed out

[@Matt-nj7ki]

I just saw your video. I think that you could also sanitize the keg, empty the keg and plug everything just like you did... the keg would fill up with the C02 and bubbles into the starsan bucket.