The title of this blog is naturally not true, since a Bourbon is very different from a Scotch Whisky, but what I mean to say is that I want to find out if the “wood-influence” of American Oak is comparable between a “New American Oak” barrel, a “Ex Sherry” American Oak barrel and a “Ex Bourbon” American Oak barrel.
I had given myself a task. A tast to compare three drams. Why? To see if I could find out if “Sherry” matured Scotch Whisky is somehow more like Bourbon than like Sherry. I tasted a “PX Sherry” just for the sake of tasting actueel Sherry.
The drams I compared are:
- Koval, Bourbon
- Compass Box, The Circus
- Corsair, Triple Smoke
Why did I select these drams?
The Koval Bourbon is mash bill that has millet as second component. This means there is little influence of spice that can come from rye that would overpower the taste. The millet gives a dimension to the taste that cannot be confused for something else, since this is the only Bourbon in the world that has Millet.
The Compass Box The Circus is the dram I selected to compare the “Sherry” influence against. Since it is not allowed by UK laws to have anything “added” to the barrel, the only influence of the “Sherry” can come from the “Sherry” that is left over in the wood of the barrel. I do not know today which kinds of barrels Compass Box uses, and it is also not disclosed in the information provided. I do know that this is a Scotch Blended Malt that is made with 100% barley. It is therefor an excellent example of a high quality dram.
The Corsair Triple Smoke is a 100% barley Whiskey. It shares one of the influences that is also present in the Koval Bourbon, being that both are matured in new American Oak barrels with a Medium Char. They both have been matured around 2 to 3 years. This means the wood interaction is comparable but not “the same”. The Alcohol / water / barrel reduction/addition and reaction processes are “comparable”.
What I noticed is that the color of the three drams is very alike indicating that wood abstraction processes have resulted in comparable outcomes. All drams are natural color and non-chill-filtered.
I had started out comparing “The Circus” to the “Bourbon” and what struck me was the “pepper-spice” nose on both. I have smelled an actual PX Sherry and nothing spicey is in the nose of this Sherry. Does this mean anything? It could, if I would know the “Sherry” background used in the Compass Box.
What I have been reading in a book called “Whisky
Technology, Production and Marketing” is this: The importance of wine contact has not been established. Constituents of sherry have been identified in whisky matured in sherry casks, but their sensory impact, if any, has not been established.
So the Bourbon and the Circus share spice notes in both taste and smell. I also tasted the Triple Smoke and that struck me is that the Triple Smoke and the Circus smell actually even more comparable to each other with respect to the spice. Since the spice cannot come from rye, and it does not come from the millet it stands to reason that it comes from the Oak.
The Koval lacks the citrus floral note intensity (they are in there but less prominent) that are present in the Triple Smoke and Circus. This is partly explained by the fact that the 51% corn. The other 49% millet give the influence, since it cannot come from the wood.
The Circus is “Complex” due to (but not alone) the blending of Malts and the added influence of wood during maturation. The overall intensity of Spice and other wood related influences is “less prominent” compared to the others, but more intense then a “Ex Bourbon” matured dram. The Circus has the most Citrus / Floral / Malt influences compared to the others. Which is logical since it is a 100% barley sources from 4 sources. Which also ads complexity.
The Bourbon from Koval gets is complexity from the combination of Millet in the mash bill which adds grain related complexity that cannot be found in the other two. But the Vanillin and Spice influence is “comparable” to the Corsair. These are from the new American oak.
The Corsair Triple Smoke is remarkably simular on the nose to The circus, but less complex since it misses the 4 component parts that the Circus has. It does however have something on the nose that the circus does not since it was smoked with three kinds of fuels. This add a smoke influence that is more prominent in the Corsair. The influence and levels of spice are higher, but surprisingly simular.
What this all tells me is that the influence of wood can be ranked in a way that is not orthodox in whisky reviews, so bare with me.
20: “High” Oak influence :
Corsair and Koval, due to fresh American White Oak, small cask, medium char. The wood influence is documented to be 20x higher for some notes, compared to the same notes in “Ex-Bourbon”.
2-19: “Medium” Oak influence :
Compass Box, due to inability of “low alcohol Sherry-oak” interaction with either an American White Oak barrel or a Spanish Oak barrel. Low alcohol (higher water) interaction “leaves” components behind that the Sherry just can’t withdraw. These are “left behind” for the high Ethanol Single Malts to interact with when used. (Before the early 1970 this was the “normal oak influence”. This was before the industry switched from “Sherry transport casks” to cheaper “Ex-Bourbon casks”)
1: “Normal” Oak influence :
“Standard” Single malts matured in “first fill” ex-bourbon. Since the influence of the “left over bourbon” in the wood is negligible just as the “Sherry” influence is. (See quote from the book I mention before) the main influence is the cask. This has become the “standard” ever since Scotsch Whisky could not used new make American oak “transportbarrels” used for shipping “Sherry” to the UK. This practice stopped after the early 1970’s.
0-1: “Low” Oak influence:
The barrels used for bourbon and first fill, when reused, can be re-charred, but this simply does not give the cask the same wood influences that a new barrel has. These casks are on the lower end of the influence scale, since all wood/alcohol interactions have just about taken place. Multiple fills will eventually “deplete” the cask.
It is quite hard for me to make a summarization of all I have learned over the past months, but the tasting of actual PX Sherry, the tasting of the corsair next to the compass box, comparing to the Koval bourbon and any other ex bourbon dram has me convinced that the “Sherry” influence is Negligible/non-excistend and that the actual “Sherry” influence should be read as “Spannish Oak” or “American Oak” influence. The nose and “sweet” taste of PX Sherry is simply not there in my view. The sweet in Sherry is a waterdesolve able influence that is to little to be registered. Also the nose and palate of the corsair and compass box are just to simular to be explained by anything else than the wood influence. The low alcohol/high water content of the Sherry, the presence of flor in a Sherrybutt and the high quantity of water lead me to conclude that “Sherry matured” malts make use of the wood flavour compounds NOT withdrawn from the cask by the “low alcohol/high water” Sherry.
Compared to “New American Oak” this wood influence is naturally less prominent than in “Sherry butts”, since the low alcohol in Sherry did actually extract some flavours. It is however more prominent than using “Ex bourbon” casks, since the high alcohol Bourbon has attracted most of the wood influences from the cask before Scotch is put in. The longer the age of the bourbon, the less wood influence is left.