Fermenting in a 19l corny keg

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I have been looking into fermenting in cornies rather than my current stainless fermenters. I usually make 10-12l batches and think that a 19l corny would be perfect. I can also fit 3 in my ferm chamber at a time and then can always transfer to my serving kegs or just directly bottle.

Does anyone do this? Am curious to hear your experience. Also is a cut dip tube enough or is it better to go floating dip tube?
 

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I do, it’s a great way to brew. Have a look at my brew day write up for how I use them. I don’t think that’s a better fermenter out there for less money than a corny with a floating dip tube.

 

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The other nice thing about using a corny as a fermenter is if you no-chill you can skip the sanitising step as the hot wort will sanitise the keg for you. I also often use the corny as a unitank and serve directly from the fermenter without transferring to a serving keg, which saves on cleaning.
 

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Not all the time, but I do on occasion use a corny for primary fermentation. I've always got something secondary fermenting with brett in cornys.

For primary, I find the dip tube doesn't need shortening too much, around 1cm, if I transfer clear wort from mash to kettle, kettle to corny. Its probably best to plan to leave a bit more in the kettle, avoiding carrying trub over.

I can ferment under pressure with a spunding valve, but often just shove an airlock on.

DSC_0070-01.jpeg


Another idea is to daisy chain another keg, gas out to liquid out, and purge it with co2 as you ferment, ready for transfer.
 

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The necessary hardware is now permanently plumbed in for fermentation. Still use secondary regulators as "spunding valves". Use "floating dip tubes" anyway. Generally, keep volume below 17.8L (19L kegs) to prevent "blow-offs" but the pressurised ferment keeps the likelihood of that minimal (as does keeping OG <1.050 and temperature <19°C ... perhaps?). A "trap" between keg and regulator alerts me of impending "blow-offs".

Fermentation under pressure deals with carbonation. Beers fermented this way are served cool (7°C-ish) so never had problems with the excess yeast in the keg causing "staling" (the beer is served from the keg it was fermented in). I consider the method essential for low alcohol (>1% ABV) beers to avoid mucking about with a "beer" that might be sensitive to infections?

It's also a very quick, and labour-saving, way to end up with drinkable beer!
 

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What I mean by "permanently plumbed in":
20220703_110309_WEB.jpg

The small Shako regulator is acting as "spunding valve". It is connected to the 4-5 BAR CO2 bus line 'cos they need the "back-pressure" to function as "spunding valves" (relieving regulator). The larger 60 PSI gauge and bubble counter is for dealing with over-pressured kegs (secondary purpose, not required for "spunding"). The large water filter housing is acting as the blow-off "trap", the input end is connected to the keg "fermenter".
 
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I do, it’s a great way to brew. Have a look at my brew day write up for how I use them. I don’t think that’s a better fermenter out there for less money than a corny with a floating dip tube.

Thanks I like the idea of purging a keg of sanitizer too. Do you just hook them up once fermentation starts?
 
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Not all the time, but I do on occasion use a corny for primary fermentation. I've always got something secondary fermenting with brett in cornys.

For primary, I find the dip tube doesn't need shortening too much, around 1cm, if I transfer clear wort from mash to kettle, kettle to corny. Its probably best to plan to leave a bit more in the kettle, avoiding carrying trub over.

I can ferment under pressure with a spunding valve, but often just shove an airlock on.

View attachment 71065



Another idea is to daisy chain another keg, gas out to liquid out, and purge it with co2 as you ferment, ready for transfer.

Good to know about the dip tube length, I might just cut the dip tube intially and see what the results are before considering a floating dip tube.
 
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The necessary hardware is now permanently plumbed in for fermentation. Still use secondary regulators as "spunding valves". Use "floating dip tubes" anyway. Generally, keep volume below 17.8L (19L kegs) to prevent "blow-offs" but the pressurised ferment keeps the likelihood of that minimal (as does keeping OG <1.050 and temperature <19°C ... perhaps?). A "trap" between keg and regulator alerts me of impending "blow-offs".

Fermentation under pressure deals with carbonation. Beers fermented this way are served cool (7°C-ish) so never had problems with the excess yeast in the keg causing "staling" (the beer is served from the keg it was fermented in). I consider the method essential for low alcohol (>1% ABV) beers to avoid mucking about with a "beer" that might be sensitive to infections?

It's also a very quick, and labour-saving, way to end up with drinkable beer!

I was thinking of serving from these kegs as well, I can always use my fermenter as a makeshift kegerator if needed. Also I will definitely try spunding at some point too.

I would imagine at 7c the yeast may still be doing some work on the beer just very slowly. I wonder if it changes the taste of the beer over time?
 

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Thanks I like the idea of purging a keg of sanitizer too. Do you just hook them up once fermentation starts?

Yup. As I usually no-chill I may keep a keg of sterile wort ready to go for up to a couple of weeks. Once I have pitched my yeast I then hook up my serving keg (if I’m not going to just serve from the original keg) and add a spunding valve/blow-off tube as per the picture below. I don’t bother purging sanitiser as the amount of CO2 given off by fermentation is enormous, and enough to reduce O2 to around 1-2 parts per billion if I remember correctly.

E60C1D3E-C81D-4876-872B-872FDE223CAE.jpeg
 
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I picked up a couple of used kegs for $45 each delivered. That's about $40 cheaper than one of the Anvil stainless fermenters I have. I am not sure why I haven't considered this before?
 
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Yup. As I usually no-chill I may keep a keg of sterile wort ready to go for up to a couple of weeks. Once I have pitched my yeast I then hook up my serving keg (if I’m not going to just serve from the original keg) and add a spunding valve/blow-off tube as per the picture below. I don’t bother purging sanitiser as the amount of CO2 given off by fermentation is enormous, and enough to reduce O2 to around 1-2 parts per billion if I remember correctly.

View attachment 71103
Ah great thanks, I didn't even consider just letting the gas purge. That's what I do right now with my kegs before filling anyway.

You have a lot more patience than I do, there is no way I could let a keg of wort sit for more than an hour. I want to get drinking it as soon as I can! Kegs are a great alterantive to the plastic jerry cans, it always spooks me thinking about dumping boiling wort into plastic.
 

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You have a lot more patience than I do, there is no way I could let a keg of wort sit for more than an hour. I want to get drinking it as soon as I can!
I think I enjoy brewing almost as much as drinking the end result. Plus with two small kids if I have the option to brew I’ll take it! Then I can always ferment another beer when a keg kicks without having to brew a new batch. Splitting the wort making from fermenting also cuts a bit of time off a brew, as does no-chilling, so makes it easier to fit in more brewing. Hooray!
 

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Yup. As I usually no-chill I may keep a keg of sterile wort ready to go for up to a couple of weeks. Once I have pitched my yeast I then hook up my serving keg (if I’m not going to just serve from the original keg) and add a spunding valve/blow-off tube as per the picture below. I don’t bother purging sanitiser as the amount of CO2 given off by fermentation is enormous, and enough to reduce O2 to around 1-2 parts per billion if I remember correctly.

View attachment 71103

What size of keg is that wee one?
 

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