A history of aging

20 August 2014

By Mitch Bechard, Western US Brand Ambassador

When talking about the characteristics of a scotch whisky it is now believed that around 60 - 80% of these come from the maturation process, but where did this tradition and lengthy process of aging scotch come from? The first written record of whisky making in Scotland dates back to 1494, however Scots were making it long before that. Originally, Scottish whiskies would have been drunk as new make spirit or ‘cleric’ straight from the still.  This is because it was either illegal or the farmers making it at the time wanted to drink it instantly, but most probably a combination of both these factors.

We believe that the first aging of Scotch whisky was an accident. There are no accounts of Scots enjoyed a dram as ‘mature’ until the 1820’s. Prior to this herbs and spices were added to make it more palatable, the first scotch cocktails.   As the demand grew for this liquid it needed to be transported further distances in casks.  During this period what was put into these casks prior was not important, as the cask was seen more as a transportation vessel.  I have read horror stories about casks used that held fish in their previous life, one whisky I would not like to try!  When casks were used not of fishy origin the liquid that was carried inside them was found to become rounded and softened by the wood and aging scotch whisky was born.  Oak soon became the preference due to its strength and the characteristics it gave.  Scottish and English oak were used at first but these trees took a long time to grow with an average age of around 70 years. Combine that with the fact that the United Kingdom is fairly small in size, fitting into the state of California very comfortably; there was not a lot of land to grow these.  Documented experiments were done using pine trees.  This was a disaster due to the resin canals passing into the whisky, luckily sap flavoured Scotch whisky never caught on! 

By the 1860s the United Kingdom had started importing sherry and it still accounts for 30% of its consumption to this day.  The abundance of sherry casks at the time excited the Scots and started the long relationship of using sherry casks to mature whisky..  It was not until the 1940s that American casks were used.   After World War II American coopers were short of work and struck a deal with the distillers to insure that all bourbon must use new wood for every maturation, this was eventually passed as Federal law in 1964.   

When looking at American Bourbon casks versus sherry casks the difference is not only obvious with regards to their size but also their inner workings. 

The Bourbon industry benefits from charring their casks where in Europe sherry casks are lightly toasted.   There are two stories as to why American wood is charred.  The first relates to the so called father of bourbon, Rev. Elijah Craig.  Supposedly he used charred barrels that he salvaged from a barn fire.  My preferred story credits the Mississippi for this. During the 17th Century, oak barrels made the 2,320 mile journey down the river containing food and other products.   To remove rotting remains in the casks prior to filling with whiskey they were “fired” in an attempt to sterilize them. It became apparent that this layer of charcoal acted as a filter and also imparted more flavour into the whiskey, therefore mirroring the situation in Scotland as the trip down the Mississippi could have taken up to 3 months thus mellowing out the spirit.  It is believed that the Mississippi could be the main reason why bourbon is aged today.

The first American casks were used in Scotland in 1946 and the relationship has blossomed ever since. From this point on the flavor profile of Scotch whisky was changed forever going from the heavy rich fruity characteristics seen in European wood to the lighter, vanilla and more delicate style within the interaction from American casks.

It is estimated that around 80% of casks now used to mature whisky in Scotland are sourced from the USA. Therefore it is no surprise that Glenfiddich has maintained a strong relationship with the bourbon industry for their casks.  This is evident through releases such as the spectacular 19 Year Old Age of Discovery Bourbon that is a tip of the hat to the bourbon industry.  Along with the new Glenfiddich 26 year old Excellence that uses exclusively the finest bourbon casks.

So next time you are having a wee dram reminisce on how that liquid got to taste the way it does today through the progression of aging, but most of all savour and enjoy every sip.

Follow Mitch on Twitter: @GlenfiddichMB