Why not ferment in boil vessel?

[robert.balsinger]

I have been no chilling wort for the last half dozen beers and then corny fermenting the last three. I am ready to transfer cooled wort today. The thought occurred to me “Why not pitch to the covered BV and ferment then transfer to serving keg?” Basement is 66F and I have a cooling jacket to keep it there. There is little O2 in BV. What is there will be pushed out the lid the first 24 hrs. It has been covered since 5 min before I got ready to flame out. No O2 transfer will make a nearly zero O2 exposure. It is an 8 g MegaPot with thermometer and outlet. Easy to refractometer test a no O2 sample.
Gravity transfer to double purged keg. If it goes smoothly a couple times I could silicone gasket the lid, add some weight to the lid and make a ball lock port in the lid for capturing CO2 to purge keg.
Anyone done this before? I am sure some have. What could go wrong?

 

[VikeMan]

It has been covered since 5 min before I got ready to flame out. No O2 transfer will make a nearly zero O2 exposure. It is an 8 g MegaPot with thermometer and outlet.

I'm not familiar with a MegaPot, but what will be keeping O2 out while the fermentation is winding down?

 

[robert.balsinger]

I'm not familiar with a MegaPot, but what will be keeping O2 out while the fermentation is winding down?

The layer of heavier than air CO2 resulting from fermentation?

That CO2 would have to be driven out to escape. Any O2 drawn in during gravity transfer would have this layer of CO2 in place as the wort level in the pot goes down. The CO2 layer is certainly not impermeable, but it will try to stay below incoming O2, I would expect.

 

[robert.balsinger]

I thought about trub being as issue but I vorlauf for 15 or 20 minutes at a slow rate. I imagine it helps complete conversion and I can see almost no husk and diminished smaller particles in these worts. There is a small amount of smaller particle hops that escaped the pellet bags, but it really is just an incomplete skim on the bottom of the pot.

I am about 2 hours from deciding on trying this.

 

[robert.balsinger]

>> If you brew in the Harrisburg/West Shore area, ask me about The Sons of Alchemy Homebrew Club.<<

When I brewed my first beers in 1995, it was on Walnut St. in Mechanicsburg at the Harvard Square town homes. I am in Columbus OH since 2000 and I miss Mechanicsburg still. It is a beautiful and historic region.

 

[robert.balsinger]

>> I'm not familiar with a MegaPot, <<
It really is just a pot. Nice bottom.

 

[Bassman2003]

It is homebrewing, so try it and find out if you like it for your beers. The downside I see is that you will have all of the hot and cold break along for the ride for the yeast to interact with. There is a reason brewers have left all of this behind for so many years even though it might not be convenient. If the boil kettle was a conical vessel with a trub dump you would be in business.

True, the fermentation will push out oxygen as long as the top is sealed. BTW, do not buy into the "blanket of CO2" myth. Gasses intermix on their own schedule. O2 finds a way in and around unless there is a barrier.

 

[robert.balsinger]

That protein being in the fermentation does what, do you think? Hazing possibly? Is flavor impacted? I haven't pulled the string yet.

 

[VikeMan]

That CO2 would have to be driven out to escape. Any O2 drawn in during gravity transfer would have this layer of CO2 in place as the wort level in the pot goes down. The CO2 layer is certainly not impermeable, but it will try to stay below incoming O2, I would expect.

Just a few thoughts here. The CO2 being produced will continuously seek equilibrium with the atmopshere. Unless sealed, O2 will enter, particularly when there is not a significant CO2 "wind" flowing outward, i.e. when fermentation is winding down. (i.e. it's not going to wait for an open transfer.)

Gases freely mix and seek their own equilibria between beer, headspace, and atmosphere, independent of whatever other gases are present. There will be some random collisions between molecules that happen to send some O2 back out, but it's a losing battle.

Here's a demonstration using Bromine (which is even heavier than CO2).

 

[robert.balsinger]

I reviewed some posts from the past and the concerns seem to be the ones mentioned so far and these:

1. tying up the brew vessel. ( i would transfer with .06 to go to the serving keg) My beers get there in about 6 or 7 days. That would work for me.
2. Some suggested putting saran wrap or other plastic between the lid and vessel. Makes sense to me.
3. Do not get curious and open the lid. Can do.

There were never any reports of off flavors reported by those who had tried it but many posts showed concerns about them. I had Covid in Jan '21 and had a 1.059 ale sit on primary for 6 weeks. I had a small aftertaste I attributed to being on yeast for so long but never thought the trub contributed.

If I go ahead in the with it in the next hour or two, I will report back in about 6 weeks.

 

[marc1]

If you are concerned about O2 exposure from fermenting in the kettle, you could transfer to your keg at the tail end of fermentation (with a few points to go) and then spund. Your beer would finish fermenting there without O2 and also be carbonated for you.

 

[twd000]

I've pondered the idea but never tried it myself. We know some trub is healthy for yeast cells.

Thought about making a true all-in-one system. Brew in a Basket style, with a tight-fitting clamp lid like the SS BrewTech Brew Bucket. mash in, no sparge, boil, chill, pitch yeast and seal the lid for pressure fermentation. Then rack to kegs with a few gravity points remaining, and leave the trub and hops debris behind

 

[robert.balsinger]

If you are concerned about O2 exposure from fermenting in the kettle, you could transfer to your keg at the tail end of fermentation (with a few points to go) and then spund. Your beer would finish fermenting there without O2 and also be carbonated for you.

That is the plan. Thanks

 

[NickTheGreat]

I would also worry about tying up your brewing vessel. I often times brew two batches in a day.

But I have looked into the Keg fermenting though. That seems like it could save some equipment and time?

 

[Bassman2003]

The impact is hard to quantify at the homebrew level. Nobody knows the level of beer you brew or the wort clarity you are used to seeing. If you asked the head brewer at Weihenstephan if he would leave everything in the boil kettle and ferment in that vessel he would probably laugh out loud. But, we know they have pristine practices for their own reasons. Brewing literature says to leave all of the "stuff" behind for optimal yeast and fermentation performance. Saying - "a little trub is good for the yeast" does not really apply here. But like a said, it is homebrewing and the only way to learn is through doing. So turn it into an experiment, take good notes along the way and learn from the experience. And keep us posted!

 

[Golddiggie]

IMO, fermenting in boil kettle means you're only able to have one batch fermenting at a time. I like having [at least] two fermenters that I could have running at any given time. I've had three, even four, batches in process at times. I also enjoy chilling the wort to pitching temperature in a handful of minutes (depending on batch size, sub 10 minutes even for the 12 gallon finished batch size we brewed).

I do have a wort strainer in the finished beer loop to keep hop matter out of my plate chiller. It's also catching a good amount of other stuff.

If you're curious about what would happen, try it out. Worst that will happen is you'll get a nasty batch that you'll dump and then have to brew again. Well, except for getting an infection that is, and having to get that out of the system.

 

[robert.balsinger]

The impact is hard to quantify at the homebrew level. Nobody knows the level of beer you brew or the wort clarity you are used to seeing.

I have brewed on and off since 1995. I do not brew competitively. My beer falls reasonably clear as I use Omega British Ale VIII in 1.044 to 1.060 bitters. SRM runs from 8 to 12. Whenever a good selection of imported bitters get pushed out of the grocery store, I make beer. In the 90's it was wine coolers. Now it is the alcoholic Kool Aid that is taking over. I don't lager, and I don't try to copy any commercial beers. I have made some great beers and some ok. I and my circle of friends drink them all. A little haze might become trendy, right?

That is the potential complication I see occurring to some degree, a little protein haze from the breaks. I vorlauf and use hop bags so routinely I have little trub. I am not expecting any serious issues. With the fermenter now abandoned, a dry red wine kit might be on my horizon.

I have received good answers to my question of who has done it and their results from several forums. The answers with advice for and against the idea are also appreciated. Thanks. I will post pictures here in 6 to 8 weeks. First, I am going to have a homebrew.

 

[dirkomatic]

I have been no chilling wort for the last half dozen beers and then corny fermenting the last three. I am ready to transfer cooled wort today. The thought occurred to me “Why not pitch to the covered BV and ferment then transfer to serving keg?” Basement is 66F and I have a cooling jacket to keep it there. There is little O2 in BV. What is there will be pushed out the lid the first 24 hrs. It has been covered since 5 min before I got ready to flame out. No O2 transfer will make a nearly zero O2 exposure. It is an 8 g MegaPot with thermometer and outlet. Easy to refractometer test a no O2 sample.
Gravity transfer to double purged keg. If it goes smoothly a couple times I could silicone gasket the lid, add some weight to the lid and make a ball lock port in the lid for capturing CO2 to purge keg.
Anyone done this before? I am sure some have. What could go wrong?

I put a ball lock post on my Chapman Steel Tank and used it to ferment, but not to boil, even though it is designed to do so. Sounds like getting a good sealing lid will be your biggest obstacle.

 

[robert.balsinger]

I taped the temp controller sensor to the lid and covered it with some of the insulating material you can see in the background. That controller matches the temp seen on the pot's thermometer. Should be sufficient. Set the controller to sixty-six. The basement temp is 68 year roundin this location .

 

[hotbeer]

4 brews back I did a ferment in the boil kettle. It was a 10 quart SS stock pot with a snug fitting lid. There was about a gallon of wort. I snugged an old bicycle inner tube through the handles assuming it'd stretch and allow the lid to lift up and release any pressure build up.

Week and a day later I was bottling. The only thing I didn't like was not being able to see what was going on as I can in 1 gallon jugs or the 5 litre jars I'm fermenting in now. I was also slightly disappointed that the beer was a tad more cloudy than I'm use to after it carbonated, but it tasted fine.

I'm not sure I'd do it again unless it's for making a sour beer and transferring a few days after pitch. But it's nothing to fear. Many do it.

Not sure I understand your comment about not cooling the wort. Why wouldn't you want to if you have the means? Typically I feel the sooner you can pitch and get yeast going and alcohol making the better protected you'll be from wild yeast and other unwanted surprises.

 

[Beholder]

Above has covered it, but I think the primary concern is oxygenation. The CO2 blanket is a myth as gaseous diffusion per Fick’s law will drive oxygen into the headspace and fermenting beer. I think transferring into kegs after a few days would address O2 concerns as long as you don’t mind the trub or have a floating dip tube.

 

[robert.balsinger]

4 brews back I did a ferment in the boil kettle. It was a 10 quart SS stock pot with a snug fitting lid. There was about a gallon of wort. I snugged an old bicycle inner tube through the handles assuming it'd stretch and allow the lid to lift up and release any pressure build up.

Week and a day later I was bottling. The only thing I didn't like was not being able to see what was going on as I can in 1 gallon jugs or the 5 litre jars I'm fermenting in now. I was also slightly disappointed that the beer was a tad more cloudy than I'm use to after it carbonated, but it tasted fine.

I'm not sure I'd do it again unless it's for making a sour beer and transferring a few days after pitch. But it's nothing to fear. Many do it.

Not sure I understand your comment about not cooling the wort. Why wouldn't you want to if you have the means? Typically I feel the sooner you can pitch and get yeast going and alcohol making the better protected you'll be from wild yeast and other unwanted surprises.

I brew British Bitters.
I understand your feeling. The cooling I use is fine for temp control but not robust enough for cooling boiling wort in a reasonable time. After the 60 min boil I put the lid on for 5 minutes and then flame out. I don’t open the kettle until I oxygenate and pitch the next day. Bacteria, yeast and mold can’t crawl in, no legs. They travel on dust and air waves. While the seal between the lid and the pot is not airtight at this time, it is hot for a considerable amount of time and an occasional spray of star San has prevented any issues to date.
In the past I didn’t like tossing the cooling water down the drain for a number of reasons. Recycling it would just cost the time I save just putting the lid on and walking away. 24 hours later, I sanitize, crack the lid 3/4” and oxygenate. I close the lid. I sanitize and crack it again enough to pitch. That is less exposure to air and potential corrupting nasties in the atmosphere than when I transfer to an empty, air filled fermenter and agitate or oxygenate in my opinion.
So, in answer to your question, that is why I do that. I am an old man. I spend an hour or two one day treating water, preparing grains and loading mash tun and HLT. The next day I heat water, mash and boil. The next day I pitch my starter. When I am about .06 points from expected FG I close transfer my bitter to double purged serving keg. I condition and natural carb to 1.9 at 62F in a crawl space. When ready to consume I load a 1 gal CO2 growler and cool my bitter to 56F. Easy Peary and since I make the same styles over and over they are pretty good. Works for me.

 

[robert.balsinger]

Above has covered it, but I think the primary concern is oxygenation. The CO2 blanket is a myth as gaseous diffusion per Fick’s law will drive oxygen into the headspace and fermenting beer. I think transferring into kegs after a few days would address O2 concerns as long as you don’t mind the trub or have a floating dip tube.

I agree. Fermentation at .06 away from FG should be enough to keep positive pressure in the vessel, right? I can get easy no O2 sample from the vessel outlet.

 

[Bassman2003]

Above has covered it, but I think the primary concern is oxygenation. The CO2 blanket is a myth as gaseous diffusion per Fick’s law will drive oxygen into the headspace and fermenting beer. I think transferring into kegs after a few days would address O2 concerns as long as you don’t mind the trub or have a floating dip tube.

If the boil kettle could be sealed like a fermenter with an airlock, I do not see any issue with oxygenation any more than a brew bucket. Why would it be any different? As long as it is sealed.

 

[sibelman]

. If the boil kettle was a conical

Of course, OP wants to use his current vessel. But Bassman's creative remark makes me wonder how well a conical might function as a boil vessel (with a TC element and suitable gaskets), fulfilling OP's one vessel dream. Probably a crazy idea, right?

 

[Bassman2003]

I have thought about the same thing looking at my Anvil Foundry. If they made this a conical and put the heating elements up along the sides, it would be a true all in one.

 

[Craiginthecorn]

I basically do this regularly with my Picobrew Z1. The keg holds the water and a separate container holds the fermentables and hops. Using a heat exchanger, the Z1 acts as a HERMS, recirculating between the keg and the Z1. After the mash ends, the wort is "boiled" in the keg, recirculating through various containers for the hop additions. The finished wort ends up in the keg. I use a JaydEd Corny Pillar to chill the wort in the keg, after which I pitch my yeast.

I sometimes substitute a Spike CF5 or Flex+ or Blichmann Cornical for the keg, depending on what sort of fermentation control I want.

 

[Elric]

I have the ferment in a kettle kit for my anvil 5.5 gallon kettle. it includes a gasket that fits snug around the lid giving you a pretty airtight seal, a grommet and airlock for the lid hole (normally has a fully closed insert on it), and some gaskets and covers for the thermometer and dip tube. It worked really well, the main reason I stopped using it was that it kept my kettle captive for the whole fermentation period so I couldn't have multiple beers brewing at a time.

 

[Beholder]

I agree. Fermentation at .06 away from FG should be enough to keep positive pressure in the vessel, right? I can get easy no O2 sample from the vessel outlet.

It’s a little tricky to estimate without having a means to measure the DO. Ultimately, it is how much sugar you need for the yeast to scrub the O2 that has diffused in. I can’t say for sure, but maybe one of the LODO guys may have an opinion on it. I typically start spunding with 8-10 points left, so I would use that as a starting point and you would get carbonation done at the same time. Taste would be your indicator if you start getting cardboard a few weeks later.

 

[VikeMan]

It’s a little tricky to estimate without having a means to measure the DO. Ultimately, it is how much sugar you need for the yeast to scrub the O2 that has diffused in. I can’t say for sure, but maybe one of the LODO guys may have an opinion on it.

The LODO guys would tell you not to expose the nearly finished beer to any O2, and I think they would be right. If you look at breweries like Bell's, they go to great pains to keep DO to infinitesimal levels when they are bottling beers to be bottle carbonated. They know that when you feed small concentrations of sugar to yeast (as opposed to the large amounts in a yeast starter or in a fresh full batch of wort), the yeast are going to eat it, but not do much, if any, dividing. So they don't need O2 to build cell wall materials in preparation for the budding they won't be doing.

 

[robert.balsinger]

I typically start spunding with 8-10 points left

Cool. Thanks. Will do.

 

[Beholder]

The LODO guys would tell you not to expose the nearly finished beer to any O2, and I think they would be right. If you look at breweries like Bell's, they go to great pains to keep DO to infinitesimal levels when they are bottling beers to be bottle carbonated. They know that when you feed small concentrations of sugar to yeast (as opposed to the large amounts in a yeast starter or in a fresh full batch of wort), the yeast are going to eat it, but not do much, if any, dividing. So they don't need O2 to build cell wall materials in preparation for the budding they won't be doing.

While O2 demand is highest in the replication phase, there are some papers that have investigated depressed yeast going back into aerobic respiration in the presence of O2 which breweries can use to accelerate a sluggish fermentation. With the pathways and conditions unclear for a yeast cell to switch back to aerobic, that’s why it’s a bit of guesswork. No harm for the OP to give it a go and see, but if it doesn’t work out, there wouldn’t be a whole lot of information to suggest what to change to get the O2 scrubbed without making a more specific science experiment out of it.

 

[bwible]

Some guys do just dump everything into the fermentor. Anvil sells a kit to allow you to ferment in their kettle. It’s been done.

I read a post within the past a week claiming the person wound up with an unusually clear batch of beer and the only difference was they dumped all the trub into the fermentor.

Long lag times/slow cooling have traditionally been frowned upon. More opportunity for contamination. The idea is to minimize the time between the end of the boil and the time you get your yeast in and established. I think there may be one or more other ill effects that have been traditionally thought of as being related to slow cooling.

Far as putting plastic wrap between kettle and lid, the gas produced does need to escape. That’s why everybody has 14 or 15 airlocks laying around.

It was mentioned earlier in this thread - don’t buy into that “CO2 is heavier than air and creates a blanket that displaces oxygen” belief. That has been disproven over and over again.

The biggest downside I see is tying up your kettle.

 

[bobtheUKbrewer2]

I ferment in a SS stockpot with loose fitting lid - even worse I open it on day 2 and day 3 to skim and remove the head - even worser no temperature control - it gets wusserer - I bottle using the jug and funnel method - on the bright side many of my beers are tasted by the head brewer of a local microbrewery who likes them a bit and offers advice where applicable - struggling at the moment with hopstands - I added 100 gm mosaic pellets to 22 litres of wort at 75 deg C, removing them at 50 deg C - beer is still too bitter - 5 gm of summit for 60 minutes the bittering hop.....

 

[bwible]

I have brewed on and off since 1995. I do not brew competitively. My beer falls reasonably clear as I use Omega British Ale VIII in 1.044 to 1.060 bitters. SRM runs from 8 to 12. Whenever a good selection of imported bitters get pushed out of the grocery store, I make beer. In the 90's it was wine coolers. Now it is the alcoholic Kool Aid that is taking ove.

I started brewing close to the same time as you.

There was Bartles and James wine coolers everywhere and then they came out with Zima.

Later, it became Mike’s hard lemonade and Not Your Father’s root beer.

Now its all White Claw, Truly and a thousand others trying to copy them. Jack Daniels is bottling Lynchburg Lemonade and punch and other sweet drinks. I heard Zima was coming out again for some anniversary.

History repeats itself.

People can get way too obsessed with oxygen. Back when we started brewing, we made good beers and nobody was writing articles about being obsessed with oxygen. In fact, people told us our yeast needed oxygen and they sold little CO2 cylinders and diffusion stones so we could add oxygen.

Where I think much of this O2 obsession comes from is the creation of NEIPA and all these guys who don’t use any hops until they throw 12oz into the kettle at flameout. Oxygen seems to really affect these beers and the oxygen obsession lines up perfectly with the rise of NEIPA and guys who want to drink beer that looks like it was scooped out of a mud puddle from a dirt road next to an Amish farm.

 

[Bassman2003]

Yeast needs oxygen at the beginning of fermentation to multiply and be healthy. The rest of the time yeast does not need oxygen but will scavenge it for you. Wort never needs oxygen. That about sums it up.

Edit - also, hops are destroyed by oxygen.

 

[bwible]

One other thing to be considered with no chill - your hops are remaining in the hot wort longer, as you are not chilling. So that should be taken into consideration and how it will affect final IBU.

 

[Velnerj]

I fermented in my boil kettle a couple of brews ago and it went just fine. I broke several rules that would make most on this thread cringe and in the end I had great clear beer that lasted for over 2 months.

I didn't seal my lid, in fact I put my temperature probe in the beer between the lid and the lip of the kettle. My kettle doesn't have a spigot so I siphoned off the yeast cake (after 2 weeks fermentation) with an auto siphon into the keg that wasn't purged. Both containers wide open.

So my advice is to go for it and my only point of caution would be about style dependence. I'm sure my technique wouldn't work for a neipa. That being said there are a lot of open fermenters used by professionals for heffeweizen Czech lagers etc. Mine was a brown ale and was great.

 

[robert.balsinger]

One other thing to be considered with no chill - your hops are remaining in the hot wortit will affect final IBU.

Great point. This batch could easily be out of balance. I will likely blend it with something later if that is the result. In future I will make much later hop additions. That is the kind of fact based info I like about this forum. Thanks again.

 

[Beermeister32]

Open fermentation - that brings up a lot of different issues and opinions...