Closed-system pressurized fermentation technique!

If you don't need razor precision, You could always use an analog bathroom scale.

Edit: 1MadScientist beat me to it!

I fill kegs by weight. 8.35#/gallon + keg weight (9.2#) = about 51#. I weigh them with a digital luggage scale I bought from wal-mart for like $10.

Thanks.
I am thinking to simplify it and use 2 primary kegs.. 2 yeast strains in same batch is on my mind for a while..
I could cut gas dip tube to enlarge volume for krasuen.

With how much wort do you fill your kegs?

diS, If my memory serves be well, I believe I had no blow-through, all contained with this one .....


10/23/11 by Mad Scientist Brewhaus, on Flickr

It really depends on several factors, e.g. yeast, temperature and pressure, to name three. How much pressure you allow during the first several days of primary fermenting. I used US-05, 65* F and the pressure around 12 psi.

This one is 1 pint short of 5 US gallons, in a 5 gallon keg.

EDIT: I also used fermcap-s. ~10 drops...

Been following this thread for years and was hoping I could contribute something. I haven't started brewing yet but am planning out my build. Because of space limitations in the fridge after installing a brewhemoth, I wanted to make something that could fit in the fridge door and be able to disconnect it without losing pressure in the fermenter if maintenance was needed, along with lots of safeguards.

Here is what I came up with combining a lot of other posts ideas, way over-engineered but it is modular enough to add or remove as budget permits, I know this can be done cheaper so please offer up substitute components and links, and I'll make updates.

Spunding Parts and Costs

Spunding Build Diagram

How much wort do you plan to put in the conical, you'll have 22gal to work with so you might not need the filter housing to control blow off.

Main reason for the filter/water bath is to scrub beer aerosol before it gets to the valve, but I can see brewing 15-20 gallon batches at some point in the future.

Have you guys been reading the yeast immobilization threads? I'm hopeful this could be a new thing in our closed systems. Very interesting stuff and of course suspect in the brewing world. So far the experiment produced a clean brew with low krausen and very low sedimentation. Check it out!

WortMonger said:

Have you guys been reading the yeast immobilization threads? I'm hopeful this could be a new thing in our closed systems. Very interesting stuff and of course suspect in the brewing world. So far the experiment produced a clean brew with low krausen and very low sedimentation. Check it out!

Click to expand...

I hear the guy doing the experiment is utterly irresistible to women, too!

(Thanks for the plug WortMonger! I remain skeptical that this could replace normal yeast pitching, but if it does the possibilities for pressurized fermentations are very cool.)

I'm just getting back into my closed system setup, now with a brewers hardware setup that has been working great.

I brewed Wednesday a simple lager and set the valve to about 2 PSI, came back next day to see it holding there. At +3 days I upped PSI to 4, and took a sample to find 45% attenuation. I just took a sample out last night and adjusted PSI to 5 (at +5 days), and have that sample degassing out overnight and will get a reading over lunch.

I plan to get the PSI up to 7 tomorrow. I wanted to check my practice of a D-rest as I've struggled with Diacetyl in the past. I was planning around 55% attenuation to take it out of the fridge and leave it at room temperature in my basement ~ 66 degrees for at least a couple of days.

I know some people have had great success with long D-rest's of up to two weeks. Also during this D-rest should I start just allowing the pressure to build up a bit? It looks like if I was around 15-16 PSI overall that would get me around 1.7 volume co2, which isn't terrible far off the end result.

-MG- said:

I know some people have had great success with long D-rest's of up to two weeks. Also during this D-rest should I start just allowing the pressure to build up a bit? It looks like if I was around 15-16 PSI overall that would get me around 1.7 volume co2, which isn't terrible far off the end result.

Click to expand...

I would go ahead and set it to carb at what temperature it is at when you pull it out for a d-rest. Then again, I'd probably let it stay in the primary temps until I hit 70-75% attenuated, then pull and set for carb at my d-rest temps. That's just me though.

WortMonger said:

I would go ahead and set it to carb at what temperature it is at when you pull it out for a d-rest. Then again, I'd probably let it stay in the primary temps until I hit 70-75% attenuated, then pull and set for carb at my d-rest temps. That's just me though.

Click to expand...

Thanks! Since fermentation is accelerated, by the time I took the next sample and let it degas I was already at 69% attenuation. At that time I took it out of the fridge and letting it rise to my basement temp around 66. I plan to leave it there for about a week and plan to ramp up the PSI to my desired carb level.

sub'd. this looks awesome since i've been looking to move away from better bottles and have a great and cheap hookup for corny's.

-MG- said:

Thanks! Since fermentation is accelerated, by the time I took the next sample and let it degas I was already at 69% attenuation. At that time I took it out of the fridge and letting it rise to my basement temp around 66. I plan to leave it there for about a week and plan to ramp up the PSI to my desired carb level.

Click to expand...

How did the ramp go? Did you get up to wanted CO2 volumes? Just curious how well it worked for you.

Using Beer Plugs® (15PSI gauge or 30PSI absolute) on 3-liter SODA bottles work great for pressure fermentation. They are special caps that vent pressure above a threshold with high quality, inexpensive one-way valves. Soda bottles (which will hold over 100PSI) make great pressure vessels. The Beer Plugs® were mainly designed to use in the racking/finishing stage for those who bottle prime. But you can get them for the 3-liter PET soda bottles #AND# you can get them for glass growlers. Both are much less costly than pin-lock or ball-lock cornies, which'll be around fifty bucks most anywhere. Here's how they work: http://www.youtube.com/watch?v=SrkRywBhuPM&feature=youtu.be

Would one of you who ferments in an unmodified sankey be willing to detail your yeast washing procedure for me?

I have been making a larger starter and saving some of that, but I would like to be able to save larger quantities from my lagers to minimize the number of starter steps I need.

MikeSpike said:

Using Beer Plugs® (15PSI gauge or 30PSI absolute) on 3-liter SODA bottles work great for pressure fermentation. They are special caps that vent pressure above a threshold with high quality, inexpensive one-way valves. Soda bottles (which will hold over 100PSI) make great pressure vessels. The Beer Plugs® were mainly designed to use in the racking/finishing stage for those who bottle prime. But you can get them for the 3-liter PET soda bottles #AND# you can get them for glass growlers. Both are much less costly than pin-lock or ball-lock cornies, which'll be around fifty bucks most anywhere. Here's how they work: http://www.youtube.com/watch?v=SrkRywBhuPM&feature=youtu.be

Click to expand...

Good product for what it is designed for, but fermentation??? Even at 3 liter that is way too small to be effective. Great bottle conditioning idea though.

RoundKid said:

Would one of you who ferments in an unmodified sankey be willing to detail your yeast washing procedure for me?

I have been making a larger starter and saving some of that, but I would like to be able to save larger quantities from my lagers to minimize the number of starter steps I need.

Click to expand...

Easy, slowly let out the pressure in the keg once beer is transferred. Then I used a coke bottle with bottom cut off for funnel on the beer port on the connector to fill with sterilized water. Once filled, shake keg and push out all the yeast you can into your collection vessel. Now wash as normal from this point on. Slowly releasing the pressure is key or the yeast will explode.

WortMonger said:

Easy, slowly let out the pressure in the keg once beer is transferred. Then I used a coke bottle with bottom cut off for funnel on the beer port on the connector to fill with sterilized water. Once filled, shake keg and push out all the yeast you can into your collection vessel. Now wash as normal from this point on. Slowly releasing the pressure is key or the yeast will explode.

Click to expand...

What do you mean when you say slowly? Over an hour? A day?

How much water do you typically add?

Thanks.

RoundKid said:

What do you mean when you say slowly? Over an hour? A day?

How much water do you typically add?

Thanks.

Click to expand...

An hour doing a psi every few minutes. I add whatever water I plan to do the initial was with. Usually this is about a gallon.

This thread inspired me to build my own setup! Just thought I'd post my build for everyone.

WortMonger said:

How did the ramp go? Did you get up to wanted CO2 volumes? Just curious how well it worked for you.

Click to expand...

It worked great. The beer cleaned up nicely. It didn't come out completely carbed. I don't think I let it sit at that level long enough. I either have a very small leak or it needed more co2 to absorb into the beer. It's slightly under carbed, but nothing a day or two at my serving pressure can't fix.

I have a red irish ale going now that is fermenting warmer than I expected (72 F). However, I believe I read that with this technique you don't have to worry as much about esters as they are suppressed more under pressure. I'll see if things settle out by tonight to the high 60s.

I brewed a Kolsch yesterday and tried out the medical O2 aeration method. I hooked up the O2 to the gas port and pressurized for 1 minute and then shook it for a few minutes. I hooked up the spunding valve and it showed 6psi so I dropped it down to 3psi where it's currently fermenting right along. Hopefully adding the pure O2 will take care of the missed FG's that I have been having lately.

I've read through most of this thread over the past few months and decided to give this approach a try on my next brew day. I've got one question (probably more later) on the process: what's the most effective way of pitching yeast? I've seen two approaches mentioned here:

1. Remove spear, transfer wort to keg/fermenter, pitch yeast, re-insert spear. Issue with this is you are not purely closed-system from kettle to fermenter; plus dealing with a sanke keg spear is a big unknown for me so I'm not sure if it will cause issues when trying to close it back up. Not sure if either is really an issue.

2. Pitch yeast into chilled wort in brew kettle (I use an immersion chiller), then transfer to keg/fermenter through tap's beer-out port. Issue with this is I'll be using a hop filter on the kettle output; I'm thinking the filter might block some yeast, especially if gummed up with hop & break.

I'm still in system-testing mode; my spunding valve seems to be controlling pressure nicely:

Borgstrom,


Is that a beer nut to 1/2" fitting on your Sankey tap, and if so where did you get it?

As far as pitching yeast, I use a method different from the two you mentioned. I use a plate chiller, so I can't pitch into the kettle. Here is my method.

Ten gallon batch in a 1/2BBL Sankey gravity fed with the help of a wort wizard. Transfer 2-3 gallons from the kettle through the hop back and plate chiller. Stop the transfer and remove the transfer hose from the Sankey and put a funnel in the tap. Pour yeast slurry into funnel (the wort wizard helps a lot here because it creates a vacuum in the keg and sucks the yeast in.) Once the yeast is pitched, put the hose back and continue transfer from kettle.

Hope this helps.

RoundKid -- it's a shutoff valve from Micromatic.

Cool idea with the wort wizard...had never heard of that...not sure how easy it would be to use with my immersion chiller.

I redesigned my gas line . I over engineered the last one that had a valve on one line, didn't need it.

Quick disconnects function whether one or two fermenters are hooked up.

6/5/2013 by Mad Scientist Brewhaus, on Flickr

Pressure fermenting 9.5 gallons of a Rogue Dead Guy.

6/5/2013 by Mad Scientist Brewhaus, on Flickr

...not sure how easy it would be to use with my immersion chiller.

Click to expand...

The type of chiller doesn't matter, how do you transfer from the kettle? Do you use an auto-syphon or do you have a valve?

Hi All,

I have read through this thread and the majority of the people do not cut the dip tubes, but I dont understand why?

I have about 1 to 1 1/2" of yeast and trub in my 6.5 gallon fermenters.
I usually scale up my recipes to finish at 6.75 gallons of wort in the kettle so that end up with 5 gallons of clear beer in my serving keg.

So with this pressurized system if I dont cut the sanke spear short I will get pint(s) of sludge any time I try to get a sample or when I transfer.

Please help me understand this process.

thanks Kevin

haeffnkr said:

Hi All,

I have read through this thread and the majority of the people do not cut the dip tubes, but I dont understand why?

I have about 1 to 1 1/2" of yeast and trub in my 6.5 gallon fermenters.
I usually scale up my recipes to finish at 6.75 gallons of wort in the kettle so that end up with 5 gallons of clear beer in my serving keg.

So with this pressurized system if I dont cut the sanke spear short I will get pint(s) of sludge any time I try to get a sample or when I transfer.

Please help me understand this process.

thanks Kevin

Click to expand...

First off, yes you will get some sludge when you sample, and when you start to transfer, but not pints worth. I ferment in unmodified sankey kegs. Last night I took a sample (about 4oz), I shook it up and degassed it for a while and then let it sit for about 20 minutes. It settled and there was a layer of yeast/trub in the glass but not much, maybe 1/2 cm. Then I decanted the liquid off into my sample beaker to take a gravity reading. No big deal.

When the beer is done and cold crashed, the yeast compacts and most of it stays put. I pour about 8-10oz in a glass before I start the transfer (it is cold, carbonated beer-I drink it). Then switch to my transfer hose and go for it. If you are fermenting under pressure, you are probably also kegging, so any yeast that gets in will just settle out anyway. You probably get some yeast when you transfer now, so what is the difference? Have you ever let your racking cane slip down into the trub? It is not like the whole cake flows into the cane, just a small divot around it, the same is true inside the keg. Once the divot is gone, everything else stays put.

If you cut the spear, you create other problems.

First, you leave beer in the keg! I don't know how much, but definitely some.

Second, it makes it harder to clean. You can't drain it completely while the keg is upright (I use an air compressor) and when you rinse it with a hose or pump upside down the water will not blast against the bottom and cascade down the sides.

Third, it makes it harder to harvest yeast. Because you leave liquid in the keg, when you try to rinse the yeast and push it out, you won't be able to get all of it.

Fourth, if you ever want to use it as an actual keg again, you want it to be complete.

Somewhere in this massive thread I believe WortMonger (the Godfather so to speak) said he cut his spear and wished he hadn't.

Finally, I would say this. You don't know until you try it. Do it at least once with the spear unmodified and see how it goes. You can always cut the spear later, you can't reattach it when you wish you hadn't cut it.

RoundKid said:

The type of chiller doesn't matter, how do you transfer from the kettle? Do you use an auto-syphon or do you have a valve?

Click to expand...

I've got a 1.5" tri-clamp butterfly valve

Borgstrom said:

I've read through most of this thread over the past few months and decided to give this approach a try on my next brew day. I've got one question (probably more later) on the process: what's the most effective way of pitching yeast? I've seen two approaches mentioned here:

1. Remove spear, transfer wort to keg/fermenter, pitch yeast, re-insert spear. Issue with this is you are not purely closed-system from kettle to fermenter; plus dealing with a sanke keg spear is a big unknown for me so I'm not sure if it will cause issues when trying to close it back up. Not sure if either is really an issue.

2. Pitch yeast into chilled wort in brew kettle (I use an immersion chiller), then transfer to keg/fermenter through tap's beer-out port. Issue with this is I'll be using a hop filter on the kettle output; I'm thinking the filter might block some yeast, especially if gummed up with hop & break.

I'm still in system-testing mode; my spunding valve seems to be controlling pressure nicely:

Click to expand...

Spears are easy to remove and reinstall after you've done it a few times. I wouldn't pitch into the BK, but that's just me. If you really want to keep it a closed system starting at the BK for some reason, you could transfer, oxygenate, and pitch all through the coupler (with check valves removed). I don't really see an advantage to this, but it certainly can be done.

haeffnkr said:

Hi All,

I have read through this thread and the majority of the people do not cut the dip tubes, but I dont understand why?

I have about 1 to 1 1/2" of yeast and trub in my 6.5 gallon fermenters.
I usually scale up my recipes to finish at 6.75 gallons of wort in the kettle so that end up with 5 gallons of clear beer in my serving keg.

So with this pressurized system if I dont cut the sanke spear short I will get pint(s) of sludge any time I try to get a sample or when I transfer.

Please help me understand this process.

thanks Kevin

Click to expand...

I don't take samples, but if I did I suppose that could be a little bit of a pain. As far as sludge during transfer, it's only the tiny portion of the yeast cake close to the diptube that gets sucked in, and then it runs clear. Depending on how flocculent the yeast is, how long the fermentation was, and whether or not I cold crash, I only get 2-6 oz of yeasty beer before it runs clear. I start out with my outgoing hose stuck in an empty jar or bottle, open the valve to let the yeasty stuff drain into that, and then close the valve and connect to my serving keg as soon as it starts running clear. The last few ounces in the keg will also be yeasty. I just watch the transfer tubing, and disconnect it as soon as it turns cloudy. If I'm paying close attention, hardly any yeast makes it into the serving keg. And as mentioned above, if some yeast does get by, it's not the end of the world.

As for reasons not to cut the spear, the ones mentioned above pretty much cover everything.

So I have read a bunch of the stuff here and am getting ready to start pressure brewing. But I have one question how long do you let the beer sit after primary fermentation for carbonation.

You could always hit it with the FiZZ GiZ 'n enjoy it right away.

mchase79 said:

So I have read a bunch of the stuff here and am getting ready to start pressure brewing. But I have one question how long do you let the beer sit after primary fermentation for carbonation.

Click to expand...

Mine sits after primary for as long as is necessary to fall clear. I'm carbonated during the tail end of primary and usually have to let pressure out during the crash cool.

2 questions please -

People have no issues with a picnic tap and the 30 ish pounds pressure created with this process, when the picnic tap is used to sample the beer/fermentation?
I saw one post where a guy lost his whole batch to a failed picnic tap and 20 pounds of pressure.

Next question-
When transferring out of the sanke I will draw off the yeast/beer until it runs clear ....then put it in the serving corny kegs.
Then what?
Do you stop right before you empty the fermenter in order to not blow the remaining yeast back into the serving keg or is that not an issue like when you empty a serving keg...I assume it is?

thanks Kevin

haeffnkr said:

2 questions please -

People have no issues with a picnic tap and the 30 ish pounds pressure created with this process, when the picnic tap is used to sample the beer/fermentation?
I saw one post where a guy lost his whole batch to a failed picnic tap and 20 pounds of pressure.

Next question-
When transferring out of the sanke I will draw off the yeast/beer until it runs clear ....then put it in the serving corny kegs.
Then what?
Do you stop right before you empty the fermenter in order to not blow the remaining yeast back into the serving keg or is that not an issue like when you empty a serving keg...I assume it is?

thanks Kevin

Click to expand...

1. No problems with the picnic tap (but I do put hose clamps on them to be safe). I brewed a saison a few weeks a go, it sat at 45psi at 85*F for three weeks until I was ready to keg it with out issue. The sankey tap has a pressure release that will blow excess pressure at 55psi as a fail safe.

2. Yes. I usually only have to pour off about half a glass. / Brew a batch larger then your kegs and then you stop when the keg is full and don't reach the sediment (then drink the rest right out of the fermenter or bottle it with a BMBF). Even if you reach the yeast, only a little will actually get picked up. It won't blow the whole cake because it is compacted, especially if you cold crash.

New to forum, so forgive me if I immediately broke every form of forum etiquette. I decided to take the plunge into pressure fermentation. I made a fancy contraption that my friends said I would be greedy not to share with the world. My setup might be pretty straight forward, but I haven't seen many people sharing the whole rig in action.





-It's a typical pin lock 5 gal keg, full length dip tube.
-Stubby cobra tap for taking gravity readings. Yadda yadda...

So coming from the gas out:

-Gas connection leading to more than enough hosing.
-Connects to a pool filter with a spare piece of 1/2" silicon tubing.
-Homemade spunding valve made from cross fitting, pressure gauge and adjustable release valve.
-The 4th connection on the cross leads to a shutoff/check valve that connects to a hose and gas connection.
Why the second gas connection you ask? WHY NOT. No it's so I can carbonate a second keg with the pressure if I wanted. I haven't tried it, but it'll work in theory right??? I don't plan on fully carbonating with it, but I suppose anything helps.

The whole thing was pretty straight forward to construct. The few problems I ran into were:
-I used an oil filled gauge, which is excessive and I suspect is giving me incorrect readings.
-The pool filter is plastic so I used extreme care when threading onto it.
-The check/shutoff valve had issues threading onto the brass cross. Is there something I don't know? I noticed the system had a leak and so I submerged the thing under water and looked for the bubbles. BAM, it was the damn check valve, I added more tape and cranked down on it. Fixed.

The hoses are all barbed to the standard flare thread, easy cleaning. The pool filter conveniently uses NPT for the two connections and has a nice little ring mount for the filter that the 1/2" tubing fits snuggly into. The silicon tubing isn't really necessary, or even at all. But I had less than a foot of expensive 1/2" silicon tubing I couldn't bring myself to toss out. I also could fill it with liquid and use it as an airlock?


First run. I brewed a batch smaller than normal and filled the keg to a few inches below the gas tube. I've encountered almost no blow off. The only blowoff material I saw was when I was skeptical that it was even fermenting so I cranked up the pressure. Built to nearly 20PSI, I panicked and released it down to about 5psi, in the process it spat some foam out the gas tube, oops but no big deal. I think the next I'll be less conservative with headspace.

Questions I have:
-I've seen a handful of pressures and regimes that people use. Input?
-I've seen people increase pressure as fermentation progressed. Should I change pressure in proportion to gravity changes?
-If it gets hotter, should I compensate with more pressure?
-Is there such a thing as too much pressure? Physical limitations aside.

toastadidaly said:

Why the second gas connection you ask? WHY NOT. No it's so I can carbonate a second keg with the pressure if I wanted. I haven't tried it, but it'll work in theory right??? I don't plan on fully carbonating with it, but I suppose anything helps.

-I've seen people increase pressure as fermentation progressed. Should I change pressure in proportion to gravity changes?
-If it gets hotter, should I compensate with more pressure?
-Is there such a thing as too much pressure? Physical limitations aside.

Click to expand...

Nice setup!

In order:

I wouldn't use the CO2 produced from the most active stages of fermentation to carbonate other beer. It contains a lot of volatiles and other things that can contribute to off flavors. Even if you wanted to do that, that setup wouldn't work very well, since you'd need the spunding valve (or an additional spunding valve) to be on the exit side of the keg you're trying to carbonate. Simply hooking it up to the line you have now could easily result in dangerous pressures building up in both kegs. If you want to carbonate naturally using the CO2 produced from fermentation, simply crank the spunding valve up to the appropriate pressure once fermentation is winding down.

The only times I increase the pressure is when I want to carbonate the beer using the tail end of fermentation.

I'd work on getting good temperature control rather than trying to compensate for poor temp control in other ways. Fermenting under pressure can reduce some of the off flavors associated with higher temps, but it's very strain dependent, and too much pressure will cause other off flavors.

Yes. Higher pressures during the most active parts of fermentation can stress the yeast and cause them to produce off flavors. Most breweries that ferment under pressure keep things under 15 psi for the first few days of active fermentation. I've also read that it's important to keep the pressure under 35 psi at all times if you plan on harvesting/washing yeast, since the higher pressures can cause unwanted mutations. I've never tested that theory myself, so I'm not sure how much truth there is to it.

I'm on day 3 of my first pressurized fermentation; everything seems to be going well so far. The Sanke keg spear removal/replacement was kind of a pain but manageable. I've got the spunding valve set at 4psi.

What is the consensus on pressure profiles? I've heard some say to ramp up pressure a few PSI per day, others say keep it low until you want to carbonate, others say to reduce pressure when you cold crash. I plan to carbonate in the keg, and then transfer to serving keg and/or bottle with counter-pressure filler after cold crashing.