Racking to secondary at 1.02 - does vessel volume matter with an airlock?

[kyle5434]

I'm doing primary fermentation in a bucket (with a loosely fitting lid and airlock), and I'm planning to transfer to a secondary vessel when the SG gets to 1.03 or 1.02.

I'm planning to use a 7 gallon Fermonster vessel with airlock for the secondary vessel, leaving the wine there for 2-3 weeks before racking to an appropriately sized glass carboy for a few weeks of bulk aging.

During the 2-3 week secondary, as the fermentation slowly finishes off, does wine volume vs. vessel size really matter? My thinking is that as long as an airlock is in place, the CO2 produced during that period would be enough to keep the wine from being oxidized, whether the actual wine volume inside the Fermonster is 6 gallons, 5 gallons, or 3 gallons.

Is my thinking off?

 

[Johnd]

You’re on track, as long as you’re actively producing CO2, you have a measure of protection. After fermentation / CO2 production ceases, the risk of oxidation increases, and it’s appropriate to get into a right sized vessel to manage head space.

 

[heatherd]

@kyle5434 it is advisable to either rack into a smaller container or top up with a similar wine.

 

[jgmann67]

@kyle5434 it is advisable to either rack into a smaller container or top up with a similar wine.

Though you're probably fine moving to the Fermonster, I'm wondering why you didn't start with it.

What are you making? If it's a red and you're racking it off the skins, I'm with Heather - might as well go to carboy at this point. You might also just want to snap your lid shut on your primary, put an airlock on it, keep the temps above 70* and wait another 2-5 days for it to completely finish fermentation. Either way, there's little danger of oxidation at this early stage.

 

[Arthur Larocco]

Yes, I agree!!

 

[cgallamo]

What kind of wine is it?

 

[kyle5434]

This one is my 2nd batch. It's a Master Vintner LE16 Cherie Merlot kit. It's been sitting happily in the Fermonster since racking. There are still a few tiny bubbles on the surface of the wine, but it's slowed down quite a bit. I'll check the SG in a few days and see how it looks.

I didn't start with the Fermonster because a) I didn't have it yet when I started the primary, and b) I like the idea of using easy-to-clean primary and secondary vessels before ultimately transferring to a carboy for aging and/or clarifying.