Too much fermenter headspace???

I'm looking at buying this cool 10 gal stainless fermenter:

http://www.dwbrewproducts.com/shop/product_info.php/gal-stainless-steel-carboy-p-78

I'd like to try using it as a single vessel (brew-in-bag, then fermenting in it), so I would need it to hold about 10 gal to start, but then it would only have about 6 gal during fermentation. Do you think the extra 4 gal of head space would have and adverse effect on the beer?

No, it's actually preferable, you'll lose less due to blowoff. In a primary fermenter, headspace is a good thing.

hanson95 said:

I'd like to try using it as a single vessel (brew-in-bag, then fermenting in it), so I would need it to hold about 10 gal to start, but then it would only have about 6 gal during fermentation.

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I do not think the design suitable for BIAB.
You really want a larger opening at the top to remove the bag. I could see problems lifting the bag when it is hot and bulging.

Also why would you want to tie up a mash tun/kettle for weeks on end just so you can ferment in it?
It really makes more sense to get a bucket for fermentation or if you have a thing about glass then a carboy.

el_caro said:

I do not think the design suitable for BIAB.
You really want a larger opening at the top to remove the bag. I could see problems lifting the bag when it is hot and bulging.

Also why would you want to tie up a mash tun/kettle for weeks on end just so you can ferment in it?
It really makes more sense to get a bucket for fermentation or if you have a thing about glass then a carboy.

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I personally wouldn't have any issue with "tying up a kettle" because I only brew one batch at a time. But your point about getting the bag out of the small opening makes sense. Maybe I'll stick with my 9 gal kettle and get the 7 gal stainless fermenter instead and have a two vessel system?

hanson95 said:

I personally wouldn't have any issue with "tying up a kettle" because I only brew one batch at a time. But your point about getting the bag out of the small opening makes sense. Maybe I'll stick with my 9 gal kettle and get the 7 gal stainless fermenter instead and have a two vessel system?

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That is a damn expensive fermenter methinks. I have a bit of a fetish about seeing what is happening both during fermentation and when cleaning the fermenter. My plastic fermenters whilst slightly opaque (no skunking) let me see there is krausen and how much trub I have (ie. is it over the height of the tap)

I used to ferment 10 gal batch in 15 gal fermenter and never had any issue.
CO2 builded during fermentation will fill head the space and prevent oxidizing.

diS said:

I used to ferment 10 gal batch in 15 gal fermenter and never had any issue.
CO2 builded during fermentation will fill head the space and prevent oxidizing.

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+1

I regularly do 15L batches in my 30L fermenters but I believe it would be safe to do even much smaller batches in the same 30L container.
My reasoning is that CO2 is heavier than Air (which contains 20% oxygen). O2 in the early stage of the fermentation process is not a problem. Once the yeast start producing CO2 that gas being heavier will quickly form a layer on top of the wort and push the air out of the airlock. The CO2 will eventually displace all the air from the container and provide protection for the wort from the adverse effects due to oxygenation.