The Rate of Maturation in the Barrel

[bluesbassdad]

I was just now reading for the seventy-leventh time about the interaction between the bourbon and the inner surface of the barrel. Something about the wording of this particular description caused me to picture that process as it might appear in real time, if only one could peek inside the barrel. ("We all live in a bourbon submarine, a bourbon submarine, a bourbon submarine...")

I visualized the process moving more slowly than the speed of growing grass, as the bourbon oozes, ever so slowly, into the porous charcoal, then even more slowly (I suppose) into the red layer, and slowest of all into the uncharred oak. As temperature changes occur, they too would propagate slowly because of the thermal mass of the barrel and its contents.

Then when tiny amounts of bourbon, carrying the flavor components from the barrel, return with equal slowness to the main body of bourbon in the barrel, the mixing process would be incredibly slow. I doubt that there are temperature variations at different points within the barrel that are sufficient to cause internal currents to form. That would mean that only the random movement of molecules causes mixing to occur.

Then I recalled that some makers move the barrels from one part of the warehouse to another, ostensibly for the purpose of exposing all barrels more or less equally to the external temperature changes. That prompted the following question.

Is the mixing effect of rolling the barrels a significant factor in the progression of the maturation/aging process? If so, would there be any benefit to rotating the barrels in place from time to time? Do any makers employ this practice?

BTW, as I write this, I am sipping WT101. (It reminds me that in its own way it's as good as Russell's Reserve, just different.) It's a little early (noon-thirty) for me, but my self-birthday present of Wild Turkey goods arrived today, and I couldn't wait to try out my WT shot glasses. I suppose I'll review them, along with the shirt, cap, and gourmet sauce, in a later post in the Paraphernalia (I'm still trying to learn how to spell that) forum.

Yours truly,

Dave "Turkey-Lover, and Proud of It" Morefield

[kitzg]

Based on what I've learned, indeed it seems all of the Master Distillers (those I've talked with or read from) feel that barrel rotation (moving within the warehouse from floor to floor and spot to spot) is a major factor. The bourbon expands and contracts with the seasons.

Thus, rotating the barrels in place does not seem important since there does not seem to be evidence that gravity effects the bourbon in the barrel.

[bluesbassdad]

I wasn't thinking about the effect of gravity per se.

I pictured rotating the barrel in place several rotations and at sufficient RPM to create a vortex within the bourbon, possibly causing more rapid mixing of the aged and the relatively un-aged bourbon -- like in a mixing bowl.

Yours truly,

Dave Morefield

[bobbyc]

This is a great thread in that it can be answered by a method of mine that I employ almost constantly, Guesswork! Beam now doesn't move the barrels in the rackhouses, they believe if you mix a barrel from the top with a barrel from the bottom, it should roughly resemble a barrel from the center cut. I would like to emphasis ROUGHLY! So rolling them to achieve mixing isn't done there. This is another reason to like Maker's , at least at present they are still doing it. To Beam's credit since most of their product is the 4 YO white label It probably wouldn't make that much difference. Gary and Mardee Regan state that they do rotate them if "Deemed Nessessary by the Master Distiller" . I will attempt to find out how much if any of that goes on. I believe there is another thing happening in the barrel to mix the contents , however slowly . That would be a " Wicking Effect". I think that as Bourbon evaporates and a void at the top of the barrel gets larger, that bourbon is carried through the charcoal and the caramelized layer and in the oak behind it , around the entire circumferance of the barrel . If it did not then the top of the barrels would dry out and sping a leak. It would be great if someone with access could drill a small hole in a barrell that had been undistubed for years and determine the actual moisture content at the top of the barrel. That being said this whole process is a slow one and it probably sees the most mixing in fall and spring. Theoretically right now the wood behind the caramelize layer is being infused with the bourbon as the 90+ temperatures cause it to expand into the wood. The coldest days of winter will have it all contracted to the void inside of the barrel. You would think that sometime after 1934 someone somewhere would have found out what all the rates of expansion and contraction are for a barrel of whiskey.

[Guest **DONOTDELETE**]

Dave wrote "I pictured rotating the barrel in place several rotations and at sufficient RPM to create a vortex within the bourbon, possibly causing more rapid mixing of the aged and the relatively un-aged bourbon -- like in a mixing bowl."

Dave all of the whiskey in a barrel was entered on the same day. It's all the same age. There can be no "aged and relatively unaged bourbon" in the same barrel unless some new raw whiskey was added at a later date. As Greg said seasonal changes do all the work. Manual manipulation of the barrel in place is unnecessary.

[Guest **DONOTDELETE**]

Bobby Cox wrote "You would think that sometime after 1934 someone somewhere would have found out what all the rates of expansion and contraction are for a barrel of whiskey."

Distillers have been at this a long time and I am sure that the rate of maturation and the effects of aging and the evaporation rates of water and alcohol from the barrels are known as precisely as possible given barrel-to-barrel and rackhouse-to-rackhouse differences by both the master distillers and their quality control staff. I'll bet this kind of information was collected in the late 1800's no matter how informally the data were collected. Just long term personal experiance on the job of simple practical distiller's would give them an intuitive knowledge of the aging process. When you have very long term family distilling experience spanning many generations that kind of knowledge adds up. It never hurts to ask these kinds of things whenever your arround a master distiller. Whether or not they will tell you what you want to know is another thing altogether. Beam me up Jim!

[bluesbassdad]

I understand that the bourbon in a single barrel is all the same chronological age, but that does not necessarily mean that every drop within the barrel has had equal contact with the char/wood, and without that contact it seems to me that it is not "aged" in the same sense as a drop that has entered and exited the char/wood.

I could understand what you are saying if the entire volume of bourbon in the barrel were absorbed into the char/wood and then expelled back into the hollow of the barrel during one temperature cycle. Obviously, that is not the case.

May we consider what might happen after a barrel is freshly filled with white dog? I assume that at most two or three gallons are absorbed as the temperature rises, leaving 50+ gallons of white dog to lie motionless in the hollow portion of the barrel. Only a tiny portion of that 50+ gallons is in contact with the inner surface of the barrel.

I further assume that of the amount absorbed some fraction (one-tenth? one-half?) is expelled back into the white dog (the bourbon that hasn't been absorbed into the wood yet) as the temperature drops. That expulsion might happen so gradually that the matured bourbon forms a layer, lying close to the interior surface of the barrel like ground fog, while white dog remains motionless, undisturbed, and unmixed with matured bourbon, throughout the remainder of the barrel.

In that scenario, during the next cycle the same bourbon, still lying close to the surface of the barrel, would be absorbed and expelled once again, and so on for every year to come. The vast majority of the bourbon in the barrel would never interact with the char/wood at all. Any mixing would occur only as or after the bourbon was eventually dumped.

If that's not what happens (and I'm betting that it isn't), then what does? Does a so-called "seasonal change" cause the bourbon to squirt out of the wood so fast that it swirls the entire contents of the barrel causing mixing to occur? Doubtful.

Does the random (aka, "Brownian") movement of molecules throughout the barrel upset my theory about the formation of a layer of matured bourbon? Do these sub-microscopic movements suffice to mix the recently expelled, matured bourbon with the part that hasn't been inside the wood yet? (One of my original questions, IIRC.)

Is matter from the interior surface of the barrel being slowly dissolved into the main body of liquid (and presumably being dispersed by Brownian movement), adding to the effect of the pumping action caused by seasonal changes?

Is there some other factor that I haven't thought of that mixes the relatively small amount of bourbon that enters and then leaves the wood with the much larger portion of bourbon that does not enter the wood during one temperature cycle?

Is there a chemical engineer or a fluid mechanics specialist in the house? I need a drink.

Yours truly,

Dave Morefield

[bobbyc]

Linn Wrote "Beam me up Jim! "

It made me think of Deforrest Kelly and how he would berate Capt. Kirk," Damnit Jim, I'm a doctor, not a bricklayer!" Then he would bitch about Jim sending a bunch of guys to the surface of a planet and getting them blown to bits and how he would have to put them all back together. And all he had to do was point a box at them and completely regenerate any thing needed. " What?" You may ask, does this have to do with the rate of maturation in the barrel , well not much really! Actually that one line delivered by" Bones" just seems to sum up Star Trek for me . It has all sorts of uses and I can imagine entire conversations using variations of that one line." Damnit Linn ,I'm a senior member, not a moderator!" or" Damnit Booker , I'm a barrel roller, not a master distiller!"

[tdelling]

>Does the random (aka, "Brownian") movement of molecules throughout the barrel

>upset my theory about the formation of a layer of matured bourbon? Do these

>sub-microscopic movements suffice to mix the recently expelled, matured

>bourbon with the part that hasn't been inside the wood yet?

Okay, let's run a back of the envelope calculation to find out.

A typical diffusion constant in a liquid is 10^-5 cm^2 / sec,

so taking the standard estimation for distance travelled, x = Sqrt( Dt ),

we get x = Sqrt (10^5 * 60 * 60 *24) = 0.93 cm / day,

or in other words, everything in the liquid is probably a centimeter

away from where it was yesterday.

That might not seem like much, but remember, a molecule is only

about 10^-6 cm in size, so it's gone a distance that's a million times

its size.

So to answer your question, Brownian motion provides a certain

amount of "automatic self mixing" that keeps things stirred up...

but we all know that stirred things dissolve much faster than

things that aren't stirred, so your original theory is correct: to

a certain extent, a barrel that's stirred regularly will age faster.

As a matter of fact, people in countries where men wear skirts

have been known to put barrels of distilled spirits on sailing

ships so that the sloshing of the waves would help things

along.

It turns out that aging is much more complex than just dissolving

the barrel... oxygen slowly diffuses into the barrel to oxidise

things a bit, acetic acid slowly reacts with ethanol to form

ethyl acetate, etc.

>Does a so-called "seasonal change" cause the bourbon to squirt out of the

>wood so fast that it swirls the entire contents of the barrel causing mixing to

>occur?

In my opinion, much more important than seasonal changes are daily

changes! How many times have you been sweating at noon, but

cold at midnight?

And finally, in regard to moving barrels around in the warehouse so that

they all taste the same: it certainly makes the blending a much easier job!

I say it's a cop out! Where's the art in blending together things that all

taste the same? ( Yes, I realize that every barrel at MM doesn't taste

exatly like every other barrel. )

Tim

[CL]

I love the phrase and the visual it gives. If only we could see inside the barrel like that.

[MurphyDawg]

But I don't want "BLENDED" whiskey, all single barrels for me!!! !!!!

LOLYeah Right!

BTW I was fascinated by the dissolving concpt, but got lost with the ######'s, cause I couldnt get past High School Chemistry , can we dumb this conversation down a bit for dope like me to understand???

TomC

[kitzg]

Dave, I take your point to be that not EVERY drop inside a barrel of Booker's (since it is dumped barrel strength) will be exactly like every other drop if there is no motion to mix those drops (or molecules) that have had the greatest contact with wood and those drops that stayed more to the center of the barrel. This is a good question or point.

Yet it is true that all of the bourbon in the barrel acquires the wonderful golden hue that comes only from being in a charred barrel. Obviously, there is not some core liquid that remains in the center of the barrel that never gets barrel char.

One of the nice things about bourbon is that it's been barrelled and drunk way before scientists and chemists could determine why things are so. Today we have an interesting mix of MDs where some are chemists and some just grew up with the stuff. Some things are done because it has always been done that way and some because science suggests there may be an improvement. Also, some changes are because it is cheaper -- which seems to me the point of not rotating barrels in the warehouse. (Thanks, Bobby, for the info!)

Anyway, good question Dave. I see your point! Maybe we can get one of the MDs to address it sometime.

[bobbyc]

Just to clarify a bit, when I said rotate barrels in the Rackhouse I was speaking of the practice of moving the barrels from floor to floor , not rolling them in place or sloshing them about. The practice of rotation used to be placing a new barrel of white dog on the upper floors and moving it down as time went along. I saw the Master Distiller from Maker's on Martha Stewart and he said placing them near the top was like having the oven on high then to move them down was like turning back the heat so it would cook all the way through. I have a Jim Beam barrel beside my BBQ grill and it is amazing how much of the sun's energy it absorbs. There is a flower pot above it and when I water it, some splashes the barrel. in the middle of these 90 degree days you can see vapor rise from it. One can only imagine the heat under a piece of tin 60 feet from the ground. One other thing if I may, It probably isn't nessessary for each and every drop of the whiskey in a barrel to travel through the caramelized layer. See elsewhere how some do not like an overly woody taste and state that some whiskey was left in the barrel too long. At some point it all becomes an homogenous mix. I also remember the Maker's guy saying that the whiskey picks up around 160 chemical compounds from the barrel.

[kitzg]

yep, Bobby, I knew what you meant by rotation and I'm surprised that any firm has stopped it. That's why I am guessing that move is to save money.

But it sure goes against the grain of the history of bourbon making -- and I can't see Booker approving one bit!

I also can't believe Bill Samuels will ever let them quit rotating.

[bobbyc]

Yeah, follow the money trail, that's all it can be because it doesn't improve the product. I spoke with a fellow who retired from Beam and he said they don't even try to find leaks any more. There used to be someone whose job was to find leaking barrels and drive little pieces of wood in them to stop it. I guess when you are sitting on 1.2 million barrels of whiskey it would make an entire career for several people to just go through and look at each one,much less repair them.

A friend of mine has a theory that is pretty universal actually . He says that anytime you have to pose the question , Why? The answer is always, Money. He says that should be the first thing they teach you at school and it should be expressed as ........? = $........

[bluesbassdad]

Tom,

Don't feel bad. I have a piece of paper in a drawer somewhere that says I used to know that kind of stuff, and I didn't follow everything he wrote either. I could use a little dumbing down too at this point.

Algebraic notation can be intimidating to those who don't use it much, and it looks even more arcane when rendered on a keyboard designed for normal alphanumeric use.

Besides, I bet if Tim, you, and I sat down together some evening with a bottle of each expression of Wild Turkey, at some point we'd understand the math as well as he.

Yours truly,

Dave Morefield

[cornsqueezins]

Wow! 160 different compounds! I would have never guessed that many. And I guess the char level would also tend to add variables to an already complex interaction.

Seems like I read somewhere that scientists (probably certain chemists) still cannot explain all the intricacies of the bourbon/barrel interactions. They probably never will which is fine by me. Linn's right (from the RR vs. RB thread), the hand of God IS upon every barrel!

Thanks fellas, this has been a great thread!

-Troy

[MurphyDawg]

BLEEEEE!!! to THAT!!

TomC

[Guest **DONOTDELETE**]

> > > MEEP > > > MEEP > > > MEEP > > >

This is a broadcast of the Emergency Bourbonic Information System

Dave wrote "I further assume that of the amount absorbed some fraction (one-tenth? one-half?) is expelled back into the white dog (the bourbon that hasn't been absorbed into the wood yet) as the temperature drops. That expulsion might happen so gradually that the matured bourbon forms a layer, lying close to the interior surface of the barrel like ground fog, while white dog remains motionless, undisturbed, and unmixed with matured bourbon, throughout the remainder of the barrel."

I do hope that no one seriously believes that this could happen.

Let's take a look at some of the forces that come into play inside of the barrel. First we have the the whiskey itself which has both of nature's solvents present; water is the solvent of inorganic chemistry and alcohol which is the solvent of organic chemistry. Then we have the barrel, and while you might not think of solid oak as a semi-permeable membrane that is exactly what it is as far as the whiskey is concerned.

Now we have two major forces at work inside of the barrel - Osmosis and Diffusion. We normally think of osmosis only in terms of water and plantlife, but it can be any liquid acting in tandem with any semi-permeable membrane. There is also a reaction between the membrane and liquid called 'osmotic pressure' that inparts kenitic energy to the molecules. Here's a good synopsis of osmosis http://urila.tripod.com/ and a quote "The conservation laws of energy and momentum require that whenever particles collide with a moving wall, they will change direction and increase or decrease their speed. Thus, they transfer both momentum and energy to the wall. Therefore, the process of elastic collisions with a moving wall is the mechanism by which the microscopic kinetic energy of the particles is transformed into macroscopic mechanical work." Now we don't think of a barrel as a 'moving wall' but that's exactly what it is to a whiskey molecule.

Now we see just how the whiskey goes into and out of the charred oak, but how does the transfer of the 'wood goody' (that's a technical term) take place between the whiskey molecules? Very simply it's called diffusion and it works in liquids as well as gases. Here's a link to a computer generated model of diffusion in action http://hex.org.uk/diffusion/ Molecules vibrate! Happy whiskey molecules vibrating against one another just like disco dancing transfer the wood goody amongst themselves (rather than the sexually transmitted diseases that real disco dancers transfer amongst themselves).

And there you have it! The forces of nature do all the work and no further human intervention is needed. The 'hand of God' is very big and comforting. We needn't understand it to enjoy it.

> > > > >MEEP > > > > MEEP > > > > MEEP

This concludes our broadcast of the Emergency Bourbonic Information Network.

You will now be returned to your program already in progress - Austin Power's in 'Goldmember'.

[ratcheer]

I used to know all that stuff, too. Now I just work with computers.

I would love to sit down with you and Tom and three bottles of WT products, sometime. We might not understand all of this stuff, but I'd bet we would learn something!

Tim

[MurphyDawg]

Shit, now there is a chemistry class I could get excited about!!

TomC

[MurphyDawg]

So is it just barrel components dissolving in the white dog that ages bourbon?? Do the chemical react at all?? Does their composition change??

Tom (The Inquisitive) C

[Guest **DONOTDELETE**]

Tom I take very holistic or Taoist view of the distilling process and see it as a seamless tapestry from the growing of the grains to the emptying of the bottle.

As far as I know all of the many components that the barrel contributes to the whiskey as it makes it's silent journy to becoming bourbon are simply held in solution. I am unaware of any further chemical reaction, but that doesn't mean there isn't any - just that I don't know if there are any.

Rather than bump an old thread I'll just copy this tidbit posted by Bourbonologist Mike Veach. "For those of you who are interested the "Journal of the American Chemical Society" January 1908 issue has an article titled "Study of Whiskey Stored in Wood". This article talks of the chemical effects of the barrel on whiskey. The study included charred and uncharred barrels, used and new barrels, sweet and sour mash whiskeys, rye, bourbon and corn whiskeys and whiskey made using the "Tennessee Process". It is a very good article well worth a trip to the library if you are interested in the subject or you can contact the Oscar Getz Museum and they can photocopy it for 25 cents a page plus shipping and handling."

I ment to pick up a copy last year, but we were very involved in 'liquid research' and it and many other things slipped my mind.

[tdelling]

>As far as I know all of the many components that the barrel contributes to the

> whiskey as it makes it's silent journy to becoming bourbon are simply held in

>solution. I am unaware of any further chemical reaction, but that doesn't mean

>there isn't any - just that I don't know if there are any.

Oh, there's definitely all kinds of stuff going on! Otherwise, you could just

make up a big batch of bourbon-barrel-extract, add it to the raw spirit,

cook it down, and you're done.

>Rather than bump an old thread I'll just copy this tidbit posted by Bourbonologist

>Mike Veach. "For those of you who are interested the "Journal of the American

>Chemical Society" January 1908 issue has an article titled "Study of Whiskey

>Stored in Wood" ... It is a very good article well worth a trip ..."

With all due respect to Mike Veach, it's a rather boring article that has very little

to say about chemistry. It's a great article if you're looking for a bunch of

mashbills from 1898 for bourbon as well as for rye. It's also an interesting

historical snapshot of what was known at the time. If anyone's really

curious, drop me a note... I think I've got a pdf version somewhere.

It's something like 38 pages long!

For those interested in the chemistry of oak interacting with bourbon,

I'll recommend http://www.cooperage.com/pdf_whtpapers/97symp_comp_oak.pdf,

which is fairly readable and has lots of nice pictures of molecules.

Of interest to the discussion here is page 8, which shows how tannins from the

wood react with the oxygen that slowly seeps into the barrel. The reaction

produces hydrogen peroxide, which then goes on to react with with ethanol to

form diethyl acetal. Pretty cool, eh? And you thought tannins were just for color

and flavor!

Tim

[MurphyDawg]

"Oh, there's definitely all kinds of stuff going on! Otherwise, you could just make up a big batch of bourbon-barrel-extract, add it to the raw spirit, cook it down, and you're done."

Thats what I was figuring, frankly. Why not just get some "essence of bourbon barrel" & a bottle of Georgia Moon and take a crack at making my own. There just had to be more goin' on.

Tom ( ) C