Micro-oxygenation and barrel size

[PSlattery]

I have a question regarding oxidation in a barrel or a flex tank. For all purposes we say the barrel is a neutral barrel, will the size of the barrel you use or the size of a flex tank change the amount of time you would let your wine age inside the vessel? Would wine in a 50L barrel add a greater amount of micro-oxygenation than a larger barrel in the same amount of time? I would think it would because of the surface area but wanted to know what everyone else thinks and how long they age there wine in smaller barrels before bottling.

 

[Johnd]

I have a question regarding oxidation in a barrel or a flex tank. For all purposes we say the barrel is a neutral barrel, will the size of the barrel you use or the size of a flex tank change the amount of time you would let your wine age inside the vessel? Would wine in a 50L barrel add a greater amount of micro-oxygenation than a larger barrel in the same amount of time? I would think it would because of the surface area but wanted to know what everyone else thinks and how long they age there wine in smaller barrels before bottling.

Yes. This is not only true for microx, it also applies to the oaky flavor that barrels impart to the wine. The smaller the barrel/tank, the shorter amount of time to leave it in, assuming all other things are equal (wall/stave thickness, wood species/density, permeability, etc.)

 

[stickman]

I agree with @Johnd above regarding barrels, but the main difference with a Flextank is that the wall thickness and surface area are part of the design, so that the oxygen transfer rate remains the same per liter no matter what size tank is used.

 

[PSlattery]

Thank you guys. I have been going back and forth between a 50L barrel and a 15 gal flex tank and I feel that with that small amount wine I would be better off with a flex tank. I do have enough wine to rotate through a barrel for the first year but will probably just hold off. I have two 15 gal Demijohns now but would want to elevate the quality of my wine in the future.

 

[Johnd]

I agree with @Johnd above regarding barrels, but the main difference with a Flextank is that the wall thickness and surface area are part of the design, so that the oxygen transfer rate remains the same per liter no matter what size tank is used.

So the smaller tanks have thicker walls than the larger ones, thereby controlling the rate of transfer? Well that's really smart, I didn't know that.

 

[mainshipfred]

Is what John is saying true in the smaller tanks have thicker walls? Interesting if it's true but I would have thought just the opposite. As far as time in a barrel since my smaller barrels are becoming or have already become neutral I was thinking of coating a portion of the outside to allow me to keep the wine in longer. @PSlattery that was a very good question that I have been pondering for some time now.

 

[stickman]

For Flextanks yes, the smaller tanks have thicker walls to reduce the oxygen transfer in proportion to the increased surface to volume ratio. In other words all of the tank sizes are designed to deliver passive oxygen standardized roughly to a second year 59gal barrel, approximately 17mg/L/yr at 55F.