Head Space in Primary?

[J-Dewey_1980]

I have only ever used the 7 gallon primary buckets and racked to 6 gallon carboys, but was recently gifted some 2 gallon fermenting buckets and one gallon carboys. I know some folks do primary under airlock and some do not, so I am not sure how that factors here, but my question is if I want to just ferment a gallon of must to then rack into a one gallon carboy, can I just put a gallon into a 2 gallon bucket (with airlock), or is that way too much headspace for primary? I appreciate any suggestions.

 

[winemaker81]

Headspace is not a problem in primary. The must is outgassing CO2 enough that it's useful to stir the must 1 to 4 times daily to introduce O2. Yeast needs O2 for reproduction, which is why fermenting wine in a closed container is not recommended.

O2 is yeast's friend but it's wine's enemy. Post fermentation is when headspace is a concern.

 

[J-Dewey_1980]

Thanks for the fast reply. Since you don't fermet under airlock, do you just cover with a towel or how do you prefer to do that step in primary?

 

[winemaker81]

Thanks for the fast reply. Since you don't fermet under airlock, do you just cover with a towel or how do you prefer to do that step in primary?

Happy to help!

I use towels over the primaries.