[morticaixavier]

so it sounds like maybe the speed with which the ethanol evaporates might be more or less constant while the deciding factor is how fast the water evaporates. If this is so then the humid conditions should yield slower overall volume reductions.

[tomsawyer]

I had thought ethanol would move out faster because it is more volatile, but maybe volatility isn't really a factor.  I think now that the components are moving through as a liquid and only volatilize near the outer surface of the wood.  In this case its only the size of the molecules relative to the porous matrix of the wood that determines relative speed of movement for a given gradient.

[tomsawyer]

This discussion inspired me to write an article for submission to Zymurgy.  I included a condensed version of this topic as well as some barrel basics (oak types and toasts) and my personal observations using small volume barrels for wine and beer.  I've written for other hobby magazines but never beer-related.  Think theres a chance this could get published or does it need to come from somebody with serious credentials?

[bonjour]

I thought Barrel Aging increased abv,  Don't you have to check for fill level every 3 or 4 days, and add a fifth to make up volume?



         




Seriously though,  I calculated the abv rise based on adding beer to a bourbon barrel, one that was "sanitized" w a large bottle of Jack,  only a small fraction of a percent increase due to product.

Fred

[tomsawyer]

My sanitizer of choice is Wild Turkey Rye, neat.  You don't need to fear the foam with this stuff, but you should respect it.