Secondary fermentation: "cubitainer?"

[sentfromspain]

So I'm looking to get some more professional supplies, and I've been eyeballing these "cubitainers" and "Bags in a box"

The cubitainers would be a benefit, because I could:
-brew a batch
-leave it in the primary fermenting container for 10/14 days
-siphon out the brew into the second fermentation containers and leave the primary fermenting container free for the next batch that I would brew the day after.

And a further benefit would be that since they are made of a semi-rigid plastic, I could do half batches for recipe experiments (this way I save on supplies) and push out the air (to an extent).

My questions are:
-Has anyone tried out cubitainers?
-Would the cubitainers or bags in a box need air locks?
-As I generally leave my brews in the primary containers until bottling, I don't know how important it is to make sure that a secondary fermenting container doesn't have any air in it. Would I have to push out ALL of the air from the container?

[Gill]

Are they just plastic cubes of a softer plastic than HDPE? Do you have a link?
I have myself been considering transferring from primary to a cube, mainly so I can chill it down to a few degrees and easily fit it in the fridge, so it settles better.

You would have to ensure fermentation has completely finished, this being the case, an airlock is not needed.

Getting rid of all the air would be favourable, but not necessary. I understand most people who transfer to secondary cannot expel all the air. However, if you have the capacity to, it would be a good idea I would think.

[Oliver]

Coming in a bit late here, sorry ...

Regarding the air (actually, oxygen is what we are concerned with here), one approach is to add a small amount of priming sugar to the secondary at the time of racking, then purge the resulting carbon dioxide as the pressure builds up over the next day or so.

Depending on the head space, 100g or so should do the trick well, but I'm sure someone knows better

Cheers,

Oliver

[SuperBroo]

My 2c worth,

Havent considered this, but sounds a good idea.

1- Forget the airlock, just leave the lid a bit loose.
2- Enough co2 will come out during sec transfer to put a co2 seal above the wort, so not sure if you would need to do a small sugar prime.

My only concern would be how would you go about properly cleaning a cube that has settled yeast in the bottom.

Otherwise, its something i reckon i could have a go at, because i could then stack more in my fermenting freezer.

Cheers,
Chris