How often to top off a barrel

I've heard recently from a commercial winemaker that he tops up every

2-3 weeks. He is concerned that if he opens it too often, he is exposing it to more O2. So that is about what I do now.

The least ullage you can create is best. Assuming you have adequate temperature control, you won't see any expansion or contraction of the wine due to temp fluctuation.

When my wines are still early (first few weeks after first racking) I check them every couple days by nose to ensure nothing bad is happening. But now, with the wines two or more months into aging, I open them up about once every 2 to 4 weeks - again, to check by nose as well as to top up.

That sounds about right to me too. I would make sure I used a really tight bung too; I got rid of the wooden one. A well sealed bung will actually create a partial vacuum. I wish i could get my hands on a small silicone one but i use a rubber one now. I have a tiny barrel,

5 gallons. I just don't rotate mine.

Joe

I check mine every week usually on a Sunday afternoon. The small amount of exposure is no worse than letting it go several weeks and finding you have quite a bit of air space and have to add quite a bit more to fill.

I keep a spray bottle of SO2 on hand and spritz the bung area and top of the wine when I top up also.

Others, obviously have different opinions.