Thursday May 16, 2024

Barrels, or casks to give them their correct name, are amazing things. Designed so that one man can move a full 500lb barrel on his own, made without any glue or fastenings and the effects they have on maturing spirit are but some of the few things that makes these wooden vessels nothing short of miraculous.

Even today, we still don’t know exactly what happens inside a barrel when spirit is matured. Through extensive research, we do have an idea as to how and why certain flavours are developed, however, we still don’t know the whole story.

The wood used to make (cooper) the casks, plays a dramatic and vital role. Oak is predominantly the wood that is used but the different species and even the trees original location will have an impact on the flavour of the spirit.

There are a few oak species that fall under the category of European oak, with each one adding slightly different notes to the maturing spirit. As a rule, European oak will develop more spicy notes. The American white oak is undoubtedly the king of barrel woods, as the vast majority of all whiskey casks are made from this. The grain is tighter and it has far less tannins than its European counterpart and has more density giving notes of vanilla and caramel.

Next we have to consider that each cask is constructed of approximately thirty individual staves. All of the staves can feasibly originate from thirty totally different trees, from thirty different locations, all with different sunlight exposure, soil minerals, climate and decomposing foliage. This undoubtedly will have an effect on how each tree grows and it stands to reason that every barrel will be a combination of multiple trees with multiple flavour contribution, giving the maturing spirit a totally unique flavour profile.

The effects of the different wood the staves are made from, can be seen if we were to fill two identical barrels. Coopered in the came cooperage, charred to the same level and stored in the same rickhouse directly adjacent to each other, the resulting whiskey character will be noticeably different from each cask.

The larger distilleries with their huge barrel inventory, need to ‘blend’ their barrels to achieve their brand profile flavour. This in itself is an amazing process performed by very skilled individuals. Samples are pulled from the selection of barrels that have reached their maturity and the blender will taste them all. They will then know in which casks to place the blended mix to produce the desired taste. When you consider the thousands of casks that these distilleries bottle at one time, these people really do have amazing taste memory and a phenomenal skill.

All whiskey barrels are charred on the inside. This is crucial to achieve what we know as whiskey. The temperature that the barrel is subjected to during the charring process will also have an effect on the flavour of the spirits matured in that particular barrel. The length of time and the intensity of the heat can be varied to meet the flavour profile requirements of the distiller. The results can range from oaky (200ºf – 320ºf), through sweet, vanilla, toasty and almond (480ºf – 520f). These flavour notes are ‘pulled’ from the barrel due to seasonal temperature fluctuations influencing the internal pressure in the barrel. In the hot summer months, the spirit heats up, expands and is then forced into the wood, past the charred layer. In the cold winter months, the spirit cools and contracts, pulling back into the barrel, bringing the desolved caramelised wood sugars from the charred layer with it. As a result, this gives the whiskey the colour and flavours we have become familiar with today.

Other articles about our Whiskey, Rum and Spirits

Our jounal about Whiskey, Rum and our process and how we do it the old fashioned Tennessee way

in the pursuit of the finest handcrafted, premium spirits

dedicated to crafting the finest of American spirits

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