Barrel Wood...toasting, barrel heads and kiln drying.

[T Comp]

I've done some research but...

Back on 11/1/2004 Ken Weber from BT posted here: "At Buffalo Trace Distillery, we first toast our barrels and afterward char them to a #4 level (55 second burn). We have experimented with several different char levels (going as high as a number 7 char, which just about destroyed the structural integrity of the barrel) to find the level that works best for us. The #4 level (in our opinion) yielded the best bourbon. By toasting the barrels (this was kind of an afterthought), we found that we could enhance the flavor of the #4 char."

Here's what Brad Boswell of Independent Stave told the Owensboro Bourbon Society on May 16, 2012 as posted on their site: "The seasoning of the barrel is key in bringing out the key flavors that each bourbon is striving to attain. Brad mentioned that on average, seasoning usually takes 6-9 months. In addition, roasting the barrel before charring can produce different flavor profiles. When discussing the 4 char levels Brad mentioned that all distilleries use either a 3 or 4 char for the barrel but many will use a 1 or 2 char for the barrel heads. Some artisan distillers are using a 2 char for their barrels however."

So what is meant or how are barrels specifically toasted before charring and who does this? Did you know barrel heads may have different char levels and who does that? Brown-Forman cooperage, in a video, says they kiln dry after air drying for up to a year. Independent Stave...do they also kiln dry after air drying? Finally, when did air drying come back in vogue as it appears that in the 50s and 60s kiln drying possibly replaced any air drying which then allowed Maker's Mark to market their return to air drying.

What got me thinking about all this is specifically is the comparison between BT and DSP 16 made wheaters and what I notice is a greater (not overwhelming but to me is there slightly) bitter wood almost soot taste in the BT wheaters versus that pure cotton candy (Randy's description and I agree) of DSP 16. Is that toasting and #4 char at BT the difference or do they do something different for the wheaters. Anybody know the barrel specs for DSP 16 even at their end run?

[Gillman]

Good questions, but answers will be hard to find I think!

I have read that the heavier the char, the more the wood sugars are consumed, potentially resulting in a less sweet - more bitter or ashy, one might infer - whiskey. Maybe the barrels used by D.S.P. 16 were less heavily charred than those used today. Or perhaps the staves were air-seasoned for a longer time than today, resulting in greater neutralization of wood tannins or some unique character imparted by microflora in the open air of the area. Or both.

I have also read that barrel head staves are dried to a lower moisture content than for side staves, by a couple of points. I don't know why this is, but it may explain why you char them less. They are drier and perhaps a heavy char might impair their holding quality.

Of course, it's very hard - impossible IMO - to say with any certainty what could account for a perceived bitter quality in a whiskey as compared to another. There are so many variables and potential explanations. What about yeast types for example, the grades and sources of the grains used, the aging environment itself (Louisville vs. Frankfort)? For example, I feel I can note a light earthy quality in BT whiskey, a "watercourse" quality, it's terroir probably, something which wouldn't have existed in Louisville or not in the same way.

Gary

[sailor22]

Great questions!

Gary probably hit it on the head when he said there were so many variables that clear answers regarding such a subtle difference would be hard to find.

Regarding seasoned wood being used in barrels, Woodford's release of "Seasoned Oak" that was darker, sweeter and wet woodier than a typical Bourbon. I think they described the wood as being yard seasoned for a year before the barrel was made but I don't recall any description of the char level or if it was pre toasted or not. In that case at least the differences weren't subtle.

[p_elliott]

We toured Independent Stave during the sampler and they told us that everyone but MM used a #4 char. That MM used a #3.5 char we didn't see any place that they could have toasted the barrel before charring. This was Independent Stave in Lebanon KY and they only sell to distilleries in KY not to the Craft guys as I understood it. They said they also only made one char a day i.e. if they were charring to #3.5 that's what they did all day no switching. They also only made 53 gallon barrels there.

[T Comp]

We toured Independent Stave during the sampler and they told us that everyone but MM used a #4 char. That MM used a #3.5 char we didn't see any place that they could have toasted the barrel before charring. This was Independent Stave in Lebanon KY and they only sell to distilleries in KY not to the Craft guys as I understood it. They said they also only made one char a day i.e. if they were charring to #3.5 that's what they did all day no switching. They also only made 53 gallon barrels there.

From Independent Stave's own site they talk about toasting barrels and do market to the craft guys and have three different barrels in their Craft Distillers Series. These differ on air seasoning time, toasted heads, heavier toast and type of wood. We also know that the Woodford Double Oaked is achieved with the second barrel being toasted twice as long but charred more lightly through their cooperage. Of course we are also in a great American whiskey period where we are seeing both experiments and permanent line extensions based on differing approaches to the barrel wood.

Here's a link to a research article James Swan did in 1993 regarding oak wood and seasoning for wine barrels. At the bottom of page 3 is reference to the study of kiln drying of barrel staves going back to the 1930'3. It states "the procedure only really came into major use in the bourbon barrel production in the early 1960's." http://findarticles.com/p/articles/m...g=content;col1

So in an attempt to answer some of my questions I will assume at least. Toasting is the same process of what is also called kiln drying. All the major distillers currently have their staves air dried for different periods and most also then toast or kiln dry. And there may have been a period of time starting in the 60's when distillers/cooperages stopped air drying and only kiln dried but have returned to air seasoning and kiln drying. Am I right or wrong at least on this?

[BFerguson]

So in an attempt to answer some of my questions I will assume at least. Toasting is the same process of what is also called kiln drying. All the major distillers currently have their staves air dried for different periods and most also then toast or kiln dry. And there may have been a period of time starting in the 60's when distillers/cooperages stopped air drying and only kiln dried but have returned to air seasoning and kiln drying. Am I right or wrong at least on this?

I'm thinking wrong. Sorry.

Kilning, from my understanding is really just a drying step. And really, if the wood could be naturally air dried long enough first, would probably be a unneeded step. Granted, i'm thinking of what I know about kilning from a woodworking perspective, but the basic principle is the same, dry the wood enough to the point where it is stable enough to work with.

Toasting, is putting more heat to the wood than kilning, just enough to give it some color, and heat the wood to bring out different flavors, but not to the point where the wood is catching fire. if it did, then you would be in the char territory.

It's like toast, air dry a piece of bread, and you get the the moisture loss, but no change in color. Put it in the toaster, and you get color from the heat caramelizing the sugars, and new flavors from this. Keep the heat on long enough, you will get char. A wholly different flavor profile.

A simple analogy, but a good one I think.

B

[tmckenzie]

Independant stave is offering a number 5 char to the craft distillers, when I spoke with them, they said many wanted to speed up the process, so they are offering this. I think it would be too much myself. We used to use kiln tried until we tried some 36 month air dried with a number 4 char, and I was so pleased with the effect it had, we have switched over to all 36 month air dried barrels. I think it will make abetter product. It seems to had vanilla sooner and seems to smooth it out faster than kiln dried.

[Bourbon Boiler]

From home experiments, I find the heavy char imparts color and aging faster, but it does not create a better product. I think it is similar to the small barrel argument, the char filters some impurities, and imparts a flavor, but lacks the caramel, cinnamon, and vanilla flavors that the lighter toasted wood does.

[Gillman]

I have heard staves can be bent using steam or very hot water, and this is a current way to make them pliable. This would not toast the barrels I believe.

Maybe this is why toasted barrels are provided, i.e. to supply the want of a light toast and its taste impact resulting from abandonment of bending staves through heating on a fire of oak waste.

Gary

[p_elliott]

Next time you're in Bardstown go tour Independent Stave it's only about 30 miles away.