Pressure regulating airlock

[TimelessCynic]

Do pressure regulating airlocks exist? Something that attaches to the top of the Carboy and only lets above a preset pressure out.

I'm thinking i would like to experiment with naturally carbonating in primary.

Thanks.

 

[RoundKid]

Carboys are not designed to hold pressure, you would be making a bomb. However, if you have a pressure rated vessel (like a keg) then pressure fermentation is awesome.

The device you want is called a Spunding valve. And for information on pressure fermenting, this thread (https://www.homebrewtalk.com/f13/closed-system-pressurized-fermentation-technique-44344/) is a monster but well worth the read.

 

[TimelessCynic]

Thanks round kid. I will have to read up on this and try it out in the future.

 

[Curtis2010]

I recently bought the valve in the link below off Amazon. Picked up the plumbing parts today to connect it to a gas side qd to turn it into a spunding valve for a cornelius keg. Plan to test it on a Bohemian Lager now in secondary.

http://www.amazon.com/gp/product/B007GDY3CU/?tag=skimlinks_replacement-20

 

[TimelessCynic]

Please share installation instructions.

 

[RoundKid]

I use that same pressure release valve from amazon. That in conjunction with a tee, a pressure gauge, and a way to hook it to the vessel and you are good to go. I don't have detailed build instructions, but the picture should give you a good idea.

 

[TimelessCynic]

Great one round. I get exactly how to do this. Do you ever get krausen coming out of the valve or do you transfer to keg off of the trub after krausen has receded?

And what makes carbing it in this manner vs artificially carbing better? Or is it just something fun and convenient to do?

 

[RoundKid]

Great one round. I get exactly how to do this. Do you ever get krausen coming out of the valve or do you transfer to keg off of the trub after krausen has receded? And what makes carbing it in this manner vs artificially carbing better? Or is it just something fun and convenient to do?

I do 12 gallons in a15.5 gallon keg so I have plenty of head space and have never seen krausen in my valve. People who ferment in cornies will use a blowoff tube at first and switch to the Spunding valve after krausen falls. You only need about 4 gravity points to generate enough CO2 to carbonate.

The things I like better about his method are:

Speed. I ferment AND carbonate in 1 to 2 weeks and then it's ready to transfer to a keg and serve. I often go longer than that, but it is nice to know I can turn beer around quickly when needed.

Closed system: from when I pitched the yeast until I drink the beer it is a close container protected by CO2.

Simplicity. I push the beer out of the fermenter into the keg with CO2. I can take samples of fermenting beer just by opening the tap (with refractometer or after decarbonating). I can look at the pressure gauge and temperature and know the beer is properly carbonated.

And yes, I just think it is fun. I like fermenting in stainless steel, and this method works well for me. If it matters to you, this method is in line with the German beer purity law as well.

Some people claim that you can ferment at higher temperatures with out off flavors when under pressure (5-10psi), but I have never tried or seen a need. I don't begin adding pressure until day 2 or 3 of fermentation.

 

[Curtis2010]

Please share installation instructions.

Very similar to what was posted except I did not add a gauge. Valve is indexed in 5 PSI increments and seems reasonably accurate.

My plan is to naturally carbonate at pressures lower than final target pressure during secondary and then give it a final bump by force carbing and confirm PSI then.

 

[Curtis2010]

Now sampling a Bohemian Pils that was the test run for my DIY spunding valve. Its way yummy and has fine champagne like bubbles that just keep going...and going...beautiful.

After testing using my CO2 regulator and valves, I discovered the scale was way off. So, I will be adding a gauge. In theory you could adjust the scale by shimming the knob up and/or shortening its trailing edge, but easier just to add a guage. Gauge also gives you positive verification of pressure in the keg.

 

[TimelessCynic]

Awesome!

Do you find the bubbles are different than when you force carb with CO2 or naturally carb in bottles with priming sugars?

 

[Curtis2010]

I perceive that they are different with the spunding valve (finer, longer lasting) than shorter duration forced carb, but don't have anything more empirical to back that up. As I recall the late great Michael Jackson made a similar comment in something I read by him.

I don't bottle anymore, but I would expected bottle conditioned beers to have similar carb characteristics because its basically the same method, but without precise pressure regulation.

Clearly more research is required. ;-)

 

[Curtis2010]

Since building a spunding valve I've discovered a few more uses for it.

Checking pressure in a keg.

Maintaining positive pressure in a keg while transfering from another keg.

Pic of my DIY spunding valve attached.

 

[TimelessCynic]

Looks cool Curtis. I want to build one but am going to wait a bit until i bring my batch size up from 5 to 10 gal.

 

[TimelessCynic]

Actually i think i may spunding earlier than later. Any difference you notice in head retention? Would it be wise to transfer beer to keg from Carboy half way through fermentation. The idea being a reduction in solids and less cleaning of the keg afterwards; no krausen in keg. I do 5 gal batches in 5 gal kegs. Thanks.

 

[Curtis2010]

Don't notice any diff in head retention...mostly a function of protiens.

I use kegs almost exclusively: primary, secondry (if applicable), serving. Push between kegs w CO2.

Sent from my GT-P5110 using Home Brew mobile app

 

[TimelessCynic]

Since building a spunding valve I've discovered a few more uses for it.

Checking pressure in a keg.

Maintaining positive pressure in a keg while transfering from another keg.

Pic of my DIY spunding valve attached.

Curtis, why do u want to maintain positive pressure in a keg while transferring? Is it something to do about keeping CO2 in solution?

I'm gonna order parts and build two.

 

[Curtis2010]

Yes, if it is already carbed that that keeps it from foaming/losing carbonation.

Sent from my GT-P5110 using Home Brew mobile app

 

[TimelessCynic]

Anyone have an opinion on the following two scenarios?

1) wait until I hit FG, transfer to keg, add sugar, attach spunding
2) transfer off trub during fermentation, try to leave a couple points worth of fermentables, attach spunding

My goal is to avoid krausen in keg and more than a pint of trub. My kegs are convex at the bottom so the dip tube doesn't suck everything off the bottom. I'm also worried that transferring off of trub to early is detrimental. Perhaps there are things in there that are beneficial for the complete fermentation cycle.

 

[Curtis2010]

If you chill your wort to your target ferm temp first (or as recommended in "Yeast" a few degrees cooler) then ferm start wont be so vigorous (esp w a lager) and thus less issues w massive krausen. Many of us homebrewers view a vigorous start as as a good thing, but it can also contribute to off flavors. For pre chilling I tranfer from boil kettle to keg (via plate chiller, keg purged w CO2), top off w Co2 at just a few PSI to reduce risk of contamination, and leave the keezer overnight to cool to ferm temp. Also a handy time to do a starter and pitch the next day.

Re krausen, not a problem w a keg. Just attach a blow off tube to the gas post. This is just a gas QD w a hose attached routed to a bottle as an air lock...or to capture the yeast. I don't usually even remove the poppet valves (unless I am doing a big ale and concerned about a lot of krausen).

I attach the spunding right after initial ferm has settled down and I dont expect any significant krausen. The nice thing about this is that your beer is carbing as it ferms so you don't have to wait for carbing at the end. You could also wait until you prime.

Re trub. For transfers from primary I have a shortened dip tube. I just cut off a couple of inches w a tubing cutter. I use CO2 to push to another keg (purge w CO2 and push in thru liquid side to minimize splashed and risk of oxidation). I draw off the small amount (typically <=1 ltr) of trub laden wort (and bank the yeast) then start the transfer. This leaves a nice yeast cake in the primary, chilled, protected by Co2, and ready for banking.

 

[TimelessCynic]

I'm ready to use my spunding. What do i set it to? Same as I would whilst force carbing with co2?


Sent from my iPhone using Home Brew

 

[acidrain]

I ferment in Sanke kegs exclusively... not to carbonate, but because it's way easier.
I built my own spunding valve using a tri-clover cap that was drilled and fitted with a compression fitting for a SS racking cane, a NPT fitting for a T that has the adjustable pressure relief valve and a gas-in post, and a third port for a thermo-probe. The thermo-probe in hind sight was not necessary... taping the probe to the outside of the keg works just as well.
The racking cane can slide up and down in the compression fitting (take the metal ferule out and use a rubber o-ring instead).

I never have to siphon, or lift.
I transfer directly from my kettle via pump to the keg already in the fermentation chamber.
It ferments there under temp control.
I don't have a gauge... I just "test" the pressure by releasing a bit to make sure it's fermenting, and the TC cap is well sealed to the keg.
I have a beer hose on the racking cane, and a beer-out coupler on the end of it. I also have an adapter that makes it so I can attach a picnic faucet to the end of the beer-out coupler.
I can take samples under it's own pressure this way.
Using just the beer-out coupler, I can transfer to cornies by connecting directly to the beer-out post on the corny.
It can't transfer under it's own pressure... that's why the gas-in post is important for complete final transfer to cornies.
I pre-purge the corny with Co2, then fill. The fermented beer never see's the light of day or the oxygen in the air until I pour a glass from my 3-faucet beer fridge.

My keg of choice for fermenting is 1/4 bbl (tall skinny 7.75 gal.) US-D Sankes.

 

[TimelessCynic]

I transferred to keg after 3 or so days in Carboy after fermentation slowed considerably. It was/is soo interesting watching the pressure gauge. For the first several days it stayed around 7 psi. I thought i stalled the fermentation transferring off the yeast sediment. Then it jumped to 10 one night then to 18 the following night. Real cool with the spunding. I guess during those first couple days at 7 psi the gas was really getting into solution.


Sent from my iPhone using Home Brew