View Full Version : Barrel Age and Effect of Wood Tannins - Comments?

03-21-2004, 19:01
Charles Thomason, a veteran distiller who started in the business before World War I, wrote notes in the 1960's on how to make good whiskey. They were printed in the 2002 Bourbon Festival Magazine, entitled, "Making whiskey in the bluegrass". Here is a quote:

"...many distilleries are going to be disappointed in the old whiskey they are going to have on hand in the next twenty years. The old bonded period was eight years. Today the bonded period is twenty years. But as I have told you of the seasons cycle, and the tannic acid is out of the wood and it begins to deteriorate, and since whiskey takes up other tastes and odors, it easily begins to take on a 'punky' or rotten wood flavor, and the longer it stays in the barrel, the more it takes up... Now this old whiskey goes down very smoothly, but leaves a 'punky' aftertaste. So if you want to taste the best whiskey with the best taste for the best price, get four-to-seven year old whiskey, for a seven year old whiskey has reached its peak of bouquet".

Thomason adds later in the article that in some modern warehouses, the air does not circulate well and also is warm too much of the time. This, he says, allows too much tannin to get into the whiskey because warmth leaches tannin from the wood but there aren't enough cold cycles to draw some of it back into the wood, as was done traditionally under Mother Nature or by careful regulation of the heat artificially. He says large modern distilleries are risking making bitter whiskey because they don't let it cycle in the traditional way.

In sum, he was saying long aging is not a good idea because ultimately too much tannin and off-taste gets into the whiskey (no matter how it is warehoused); and also, there is a risk of tannic whiskey even with moderate aging because the modern warehouses of big producers (he seems to assume) are not properly ventilated and/or too warm.

My impression of modern long-aged whiskeys, and younger whiskeys made by the big houses, is that they do not reveal the tastes he is talking about.

I enjoy well-aged whiskey and while clearly it shows more of the barrel than younger whiskey, I don't detect the adverse effects Thomason predicted. Nor do I see them in younger whiskeys aged on pallets in modern warehouses. Just tonight I had a Jack Daniels, which I assume is aged in modern warehouses. It tasted of fresh wood and corn and butter with light char flavour and the perfumed taste it is known for, nothing punky about it. I have had some old scotches that have the taste he is referring to, it is the taste of old wet wood, old wet oak, slightly musty. Rarely if ever have I noticed this in bourbon old or younger, however.

Was he too pessimisitic about the ability of modern methods to produce (old or young) clean-tasting whiskey?


03-22-2004, 09:48
Continuing my thought process: maybe whiskey barrels manufactured today are processed such that, even after they lose significant tannins to the spirit, they will not deteriorate, or deterioration will be slowed down. (Maybe through how the barrels are seasoned and dried today). Thomason was suggesting that once barrel wood is depleted of tannins - a natural preservative - the wood can start to deteriorate and communicate off-flavors to the spirit.

The California brandy-maker who responded to my question about toasting and charring of cognac barrels told me that because cognac can be kept to great age (e.g., 30 years and more), great care must be taken to ensure the barrels do not fall apart after such lengthy utilisation. Of course, new barrels are used for bourbon - that will tend to preclude this problem because by definition new barrels contain lots of tannin. Since brandy aging relies on used casks to a significant extent, used wood, containing much less tannin than new wood, has to be "managed" in a way that ensures it will remain clean and the bugs won't get to it. Still, Thomason mentioned that long storage of bourbon barrels can lead to similar concerns.

Yet as I said, modern bourbon, no matter how old in my experience, rarely if ever discloses off-tastes from the wood. So, either casks are made today in a way to minimise this risk or careful mingling of barrels is done to ensure a balanced palate results with no such flavours showing through.

I recall now once having an 18 year old Canadian whisky that had precisely the punky taste discussed by Charlie Thomason. Since Canadian whisky is matured in used cooperage, that makes sense to me: the barrels - and maybe the bottling was from a single barrel - had lost much of their tannins and something in them went awry and got into the spirit. I have bought this brand since and it was fine each time: that one time the flavor escaped the tasting panel in the distillery; it happens..


03-25-2004, 20:56

This is very interesting.Thomason seems to imply that the barrel wood can deteriorate because of the lack of tannins.
The tannins are drawn into the bourbon and because of the lack of circulating cool air,do not absorb back into the wood.
I would assume,though, that most of the aging whiskey is tasted
periodically, with only the certain ones allowed
to further mature in the barrels.

I wonder the percentage of barrels that
must be destroyed because of this so called "punky" taste ?

Another question would be "How do the tannins affect the taste of the whiskey? Would the taste of the whiskey be
different if the tannins were allowed to be drawn back into the wood before dumping? Does the temperature(at dumping time) affect the quality of the product?

03-25-2004, 21:15
Very valid points. I don't know if distilleries consciously look at these issues, e.g., in the terms Charlie Thomason was discussing, but no doubt taste issues relating to these areas are worked out through careful barrel selection and of course mingling to get the taste profile the company aims for.


12-02-2004, 20:19
someone told me you get a more woody taste with the higher proof that now goes in the barrels-in the old days a lower proof was what went in to the barrel Berncow http://www.straightbourbon.com/forums/images/graemlins/banghead.gif

12-02-2004, 20:26
someone told me you get a more woody taste with the higher proof that now goes in the barrels-in the old days a lower proof was what went in to the barrel

I believe that Wild Turkey distills and barrels their bourbon at a low proof, and that this is one of the reasons that their whiskeys are so... well, for lack of a better word, "full flavoured". To be honest, I am still on the edge about whether I like this full flavour or not, but you must respect it, and the more Rare Breed I have, the more I warm up to it.

12-02-2004, 21:31
well, Rare breed is also my favorite so I guess both of our ideas meet at the same bottle.

02-03-2005, 05:11
I enjoyed reading the above comments. Rare Bread is also my drink of choice. Well, actually I enjoy that and the Kentucky Spirit( the Wild Turkey SB).