Primary in a Corny - how much headspace?

3 gallon batch in a 3 gallon keg? I don't think so. A 2.5 gallon batch in a 3 gallon keg would be tight, but probably possible with low temperature, low gravity fermentations. Might be a good time to try Fermcap-S. (I haven't used it, but people say it's the tits.)

 

I think he's saying he will ferment in 5 gallon kegs and then package in one of the smaller kegs.

[edited for clarity]

 

In that case, then yeah, there's more than enough headspace for 2.5 or 3 gallon batches.

 

Yeah I think so too. Except for maybe like a hefe, where the yeast sometimes goes crazy.

 

Fermenting in kegs (any size) sounds like a bad idea on the surface due to cleaning issues (much like plate chillers)...convince me it's not

 

I ferment lagers in a five gallon keg with a dip tube I bent so it points horizontally about 0.5 gal above the bottom. I only use it for lagers because of headspace concerns, but I can usually package close to 4.5 gal because the krausen fits so nicely between the 5 gal marker and the lid.

It’s great because you can just cap it by throwing the gas post on , then pressure transfer with a jumper to serving keg.

Cleaning isn’t bad, just do it right away and give it an inverted soak in pbw in a bucket.

With ales, I’d give it way more headspace though..

 

@pweis909 - Yep, I bent it just in case I decided I might want to bend it back. I also thought it might pull clearer beer if pointed slightly upwards, but this proved extremely difficult with just a spring pipe bender.

The other thing to note is that if you bend the dip tube, you have to keep checking you can still curl it in through the liquid post as you go , for obvious reasons... so there is a limit to how much 'bend' you can get into it...

 

I should add, I think fermenting in a 5 gal corny for 3 gal batches is an excellent idea, you can cold crash without worrying about suck back, you can pressure transfer with ease. Hope it works out for you.

 

I use a 3 gal keg to brew 2.5 gals batches, I cut the dip tube (guessed at it), and usually only get about 4-10oz of trub out when I go to press transfer to serving keg. I also us a spunding valve during fermentation. Clean up is about the same as with serving kegs, pbw soak and rinse.

 

If I had a corny, I might use it as a fermenter. Just today I ordered two 24" tall glass vases as new fermenters, 6" diameter for 2-gallon batches, and 4" diameter for 1-gallon. I have a theory that lack of depth has been reason why most of my recent batches all taste bland and oxidized compared to past batches when I was making 2.5 to 3 gallons. I've eliminated many other variables including water source, yeast, hot and cold side oxidation. I think I might just need tall narrow fermenters to put more pressure on the yeast and limit exposure to oxygen (less surface area on top). But anyway.... somewhat related, but also I digress.

Cheers all.

 

Hmm.

 

I think you're right, pressure suppresses esters. As to whether it's unimportant at a homebrew scale, that is exactly what I intend to find out, not guessing but to KNOW with CERTAINTY. I might be wrong. But... I might be right.

 

I was referring to physical depth -- the height of the beer in the fermenter. My hypothesis has more to do with oxygen ingress and less to do with pressure and esters, though I confess I really don't know what exactly to expect from a side-by-side blind tasting (which yes I do intend to do). My hypothesis is basically that when I'm using a 3-gallon carboy to ferment a 1- or 1.5-gallon batch, and it's only like 5-7 inches deep and 8 inches wide, there's a lot of surface area and not much depth for diffusion or absorption of any oxygen from any source (post-racking to bottling bucket especially) into the beer which might cause maximum oxidation compared to almost anyone else on the planet making 5 or more gallons where the oxygen might be diffused or absorbed down a few inches into the beer but unlikely down the full 15-20 inches depth of the beer, and certainly nothing like commercial breweries that are many feet deep where I'll bet there's like zero oxygen below the first foot or two of beer at the top of the fermenter.

I'm probably nuts, and I don't blame anyone for thinking so. But I'll soon have some answers to my own questions and ponderings and will satisfy my own curiosity. And scientific experiments involving beer are fun anyway.