Whisky aficionados can tell you the brand they like, but only a few know that European and American white oak barrels change both the texture and flavour; the length of aging is also an important factor.
Of all oak quercus alba (American white oak) seems to be more suitable for whisky, and for matter, other spirit aging i.e rum.
Cognac and Armagnac distillers use Limousin or Troncais oak and Gascon oak for Armagnac.
Of late, Hungarian, Slovenian, Russian, and Romanian oak barrels are being marketed, but only to wineries.
European oak is tighter grained than American white oak, which imparts a more intense vanilla flavour to any alcoholic beverage aged in it, and for that reason, many caring winemakers prefer French oak for their chardonnays.
Australian wineries specializing in shiraz like American white oak barrels as their wines are higher in alcohol, and contain high extract levels.
Scotch, Canadian and Caribbean distillers traditionally use American oak barrels that have been used once only for Bourbon whiskey aging. Scotch distillers buy from sherry wineries American oak barrels employed or oloroso aging,.
Canadian whisky producers buy directly from their American counterparts and use it for rye whisky aging.
Now, Scotch distillers have started finishing their aging regimen in barrels previously used for Madeira, Port, Marc de Bourgogne, red Bordeaux wines, rum and call it finished in ….
All variations offer new and appreciated taste dimensions.
The size of the barrel is also of importance in the aging process, as is the toast level of the barrel, which may be Light, or Medium, or Dark.
Large size barrels help mitigate oxidation.
When whisky comes out of the still, it is colourless and very harsh. During aging, it acquires a yellowish colour and becomes mellow, as well as more palatable.
The age of aging influences smoothness, but most experts claim that the mellowing effect stops after 18 years.
Each year the spirit loses an average of two-and-a-half per cent of the volume.
The colour of the whisky comes from the addition of caramel. Distillers may use up to 2 ½ per cent of caramel. Some use less, others prefer not to use any.
There are sufficient numbers of whisky drinkers who appreciate the nuances aging techniques impart, and are willing to pay extra for the privilege.
Oloroso and port barrel finished whiskies are more popular than others.