Is a krausen necessary with kveik (or any yeast)?

[General Sterling Price]

Might seem like a silly question, but is a krausen necessary with a fermentation?
Like, if I were to conduct a fermentation completely in a carboy, fully topped up
with a blow off tube affixed, would blowing out the krausen negatively affect it?

I'll be using a kveik yeast, but i'd like to know about other yeasts as well.

Thanks.

 

[WayFrae]

You’d lose a lot of yeast that way. Some of the healthiest yeast is in the krausen. It would be better to leave some headroom so you don’t lose all of it.

 

[day_trippr]

By "blowing out" do you mean krausen leaving the fermentor? Which would imply the presence of krausen, which makes your question confusing to me. The constant loss of krausen would mean you're also losing yeast, and at some point I suppose that might affect outcomes...maybe. I've never had that happen - yet.

fwiw, around 5 PM today I pitched hydrated S04 to 11 gallons of 1.107 stout split between a pair of carboys, and when I hit my brewery to pull a pour just now I noted that though there is not yet obvious krausen, according to the submerged end of my double keg daisy-chained fermentation gas purging line, it is already outgassing at a steady clip. That won't last for long but it does confirm it can happen

Cheers!

 

[WayFrae]

By "blowing out" do you mean krausen leaving the fermentor? Which would imply the presence of krausen, which makes your question confusing to me. The constant loss of krausen would mean you're also losing yeast, and at some point I suppose that might affect outcomes...maybe. I've never had that happen - yet.

fwiw, around 5 PM today I pitched hydrated S04 to 11 gallons of 1.107 stout split between a pair of carboys, and when I hit my brewery to pull a pour I noted that though there is not yet obvious krausen, according to the submerged end of my double keg daisy-chained fermentation gas purging line, it is already outgassing at a steady clip. That won't last for long but it does confirm it can happen

Cheers!

The way I understood his question would be re-worded this way: would having no headspace and blowing off all the krausen into a tube be detrimental to the fermentation?

 

[General Sterling Price]

By "blowing out" do you mean krausen leaving the fermentor?

Yes. If the carboy was filled up to the brim so that any potential krausen were to be blown out. I know brewers will attach a blow off tube for the possibility the krausen will spill over, but they probably aren't starting with a completely full carboy.

 

[General Sterling Price]

The way I understood his question would be re-worded this way: would having no headspace and blowing off all the krausen into a tube be detrimental to the fermentation?

Yes....exactly. Thanks for the re-word (English is only my first language...lol).

 

[WayFrae]

I’m sure it will still ferment but might not be as good as if it had more headspace. Might as well try it and report back here

 

[McMullan]

Is a bigger carboy necessary?

 

[day_trippr]

I would be concerned about beer loss as well as the resulting mess - for sure, literally filling a carboy with pitched wort is going to require extended KP duty unless somehow contained by a capture vessel, but it's going to convey beer along with krausen if there's a yeasty Vesuvius happening

 

[Jeroen79]

yeah sounds like a mess to me to, and what is to gain?

 

[General Sterling Price]

and what is to gain?

It's just that I only have carboys available for use right now, and while I could possibly use 2 of them (half full) I was just wondering if I could "get away" with a full carboy (providing that the lost krausen wouldn't effect the ferment too much).

I get it...."beer loss" and all...but didn't home brewers used to skim the krausen off at one time? Also, I thought the Charlie Papazian blow off thing was centered around getting the krausen out of the ferment, or am I mis-remembering what that was all about?

Is it just a matter of threading the needle (so to speak), and guesstimate how much space I should leave?

 

[McMullan]

‘Skimming’ is timed to not waste yeast. More about harvesting yeast. There’s even more headspace in those FVs than most, in reality. You’re asking something like “what’s the best way to overfill an aquarium full of fish”. If you insist on overfilling it, you need to think about extending its volume to accommodate a krausen and perhaps using a yeast strain that doesn’t produce a whopping head of yeast foam. What kind of beer are you planning to brew?

 

[mac_1103]

Hook your blow off tube up to a second carboy. Apply for a patent. Call it the auto-top-cropper.

Seriously though, brew a smaller batch so you can leave some head space. Or brew a bigger batch and split it into two carboys.

 

[kevin58]

I wouldn't fill a fermenter to the very top... carboy or not. If all you have available is a couple of carboys then split the batch between two of them.

 

[Spivey24]

Might as well just pull some wort out and save it for a starter. You’ll end up losing most of it anyway. But if you go with no headspace just keep your temps lower than the lowest recommended and don’t overpitch and you should be fine.

 

[General Sterling Price]

What kind of beer are you planning to brew?

It's was supposed to be a simple SMaSH brew with 2 row, and Hallertauer hops...but I decided to try a pound of toasted oatmeal (quick oats) with it.

I'll probably go with 2 carboys (half full) with this one....I have a Cooper's kit I'll do the blow off method with, and judge whether it's too much of a waste, or a hassle.

More research last night seems to indicate that removing the krausen won't really affect the fermentation, the only issues would be loss of beer, and mess.

 

[General Sterling Price]

Hook your blow off tube up to a second carboy. Apply for a patent. Call it the auto-top-cropper.

Hahaha....well, I'll have to cut you in for half then!

Seriously though, brew a smaller batch so you can leave some head space. Or brew a bigger batch and split it into two carboys.

Yeah...I'm gonna go with 2 carboys half full for this one. I'll try the blow off method with a Cooper's kit I have kicking around, at a later date.

 

[General Sterling Price]

If all you have available is a couple of carboys then split the batch between two of them.

This is what I'll do. I have a syrup kit I can experiment with at a later date.

 

[Clint Yeastwood]

I've been using Fermcap to keep the foam down. The beer seems fine.