I'm curious to hear from people who have experience with wood chips and other oak alternatives such as spirals. Do you use them in a barrel or in a non-reactive container such as a stainless steal tank? What, specifically, do you think they're giving you?
The idea is that they are supposed to be either a complement to or substitute for a barrel, but an age accelerator in both cases, yet the more you think about it, the less like a barrel they seem. They're more like tea, an infusion, although you have to be careful with heat lest the alcohol evaporate.
The whiskey might soak into the wood but how do you get it back out? Some compounds will dissolve into solution, but part of the action in the barrel is the expansion-contraction that isn't occurring in a non-reactive container with chips.
Don't the chips all float to the top? I.e., they're not adding much to wood contact.
Some alternative ideas. What would happen if you:
(1) Pulverized the chips, added the powder, then filtered out the solids after 'aging.'
(2) Cooked the new make and chips under pressure until the chips become saturated, then pressed out the spirit.
(3) Loosely packed the container (barrel or non-reactive) with chips, then spirit.
For those who don't know me I'm a writer, not a distiller. I'm asking not for any particular article, just general curiosity.
I can show you a comparison of charred vs toasted oak sticks in a very short time. The hobbyists are experts on this type of flavoring.
http://www.artisan-distiller.net/phpBB3/viewtopic.php?p=24022#p24022 By the way on that forum I am pint o' shine
Neat experiment pint. you continue to give great info and advice, Thanks!
I use chips for flavoring, and rely on slow fermentation and careful cutting to manage spirit youth. I put chips and small planks (1"x3"x1/8") with the spirits in a stainless drum after barrel aging. They (mostly) sink after a few days.
Diffusion carries components in and out of the wood. Unless somebody shows me an physics analysis and data (that disproves a simple diffusion model), I'm skeptical about 'thermal cycle pumping' that I've heard often - but only anecdotally. I'm not doubting that thermal cycling has an effect, by the way, just the mechanism. The diffusion from chips happens quicker than you might imagine. Put a couple ounces of chips in a gallon glass container and top up. You can watch the color flow out of the wood and pool in the bottom, then diffuse up the container over a few days. In a matter of weeks, the optical density appears to stabilize.
Woodchips by themselves aren't going to do any microoxygenation, like a barrel would. And they won't act like a membrane, allowing differential diffusion against the atmosphere, like a barrel. I'm not sure they contribute to 'aging' at all. They will provide area for surface-driven reactions - if any are happening. Perhaps more area than a barrel, depending.
Chips are really handy for exploring variables. Extraction/total wood (related to barrel size, sort of), entry proof, cooperage, forest, seasoning, toast, char, non-oak woods. Easy to set up lots of 4 oz trials. The exact profile would have to be confirmed at full scalle barrel & time - but it can teach you a lot about effects and direction of trends.
Does anyone know of a source for port, sherry, or wine barrel chips?
I just heard of a distiller recently that was getting positive reviews for a "whiskey" using spirals. Heard they were using a SS tank with the spirals. I'll see if I can find more info.