The first demand for aged whisky started at the end of the 18th century. By the early 1800s, the term ‘old whisky’ entered the vernacular and became the most popular brand prefix in the 19th century. This emboldened less scrupulous members in the trade to devise maturation short cuts to imitate the flavour and colour of aged whisky. In industry-speak, this is called cheating Mother Nature.
Having been involved in a number of accelerated maturation experiments and the opportunity to taste many experimental products from competitive accelerators, you discover each process brings biases.
In the quest for the Holy Grail of complexity, balance, enrichment and long finishes these interventions mask, substitute, remove, add and accentuate flavours. This can be an asset if you are making whisky for cocktails or mixers where the manipulated flavour profile marries with other liquors and gustatory ingredients.
In 1738, an early recipe, using the Anglicised spelling of whisky which first appeared in 1735, called for cloves, nuts, raisins, mace, caraway, anise, sugar and other spices indicating early malt spirits were flavoured with spirits and liqueurs, not wood. At the time when wood maturation programs began, wood substitution recipes started to be propagated, such as burnt sugar for the appearance of age and Bohea tea or tobacco for ‘seasoned flavour’. The prevailing orthodoxy was to seek a clean spirit for ‘whisky must be purified, the product rectification removes contaminants which render them disagreeable or highly injurious’. Then you added flavours to ameliorate the whisky.
In 19th century North America, charcoal filtration was the most popular method to rectify spirit.
During the past 200 years, hundreds of accelerated maturation patents have been issued, from electrical charges, vapour treatment, shaking machines, pressurisation, aeration, steam coils through barrels and heat cycling to barrelhouse design.
In industry-speak, this is called cheating Mother Nature and beating Father Time
Some techniques were borrowed from the brandy and rum industries, such as tranchage (heating new make), boise (boiling oak chips to syrup) and paxarette (seasoning exhausted casks with boiled down grape juice and fortified wine).
Many countries have banned these processes. After the repeal of US Prohibition in 1934 there was an acute shortage of old whisky, so ultra-violet exposure, sonic rays (‘aging whisky in hours’), charred grates to oxygen and ozone diffusers were tested and patented.
On discovering an Australian whisky distillery was experimenting with isotopes in 1961; the Scotch whisky industry rushed to the Atomic Energy Authority facility at Wantage for irradiation. Between the failed experiments and the fear of a Frankenwhisky, the nuclear option ended.
Wood treatment is another time-proven method. Rifling and honeycombing the internal staves, adding inserts and chips, to smaller capacity casks.
In the 1930s, the University of Pennsylvania conducted sonic tests making the extravagant statement: ‘intense sound for seven hours will age whiskey by the equivalent of four years in wood’.
My favourite is the patrician Maryland distiller, Outerbridge Horsey IV. From 1886, he regularly sent his rye whisky from Burkittsville, around the Horn to San Francisco.
Then the barrels were shipped by rail back to his Needwood Distillery for bottling. The effects of the ocean, crossing the tropics twice and the continental train trip, mellowed his Golden Gate whisky so he could sell at a premium. Other distilleries sent their whisky on return trips to Cuba and Rio.
In the 1930s, Edradour, Distillery producer of King’s Ransom, put whisky casks as ballast on cruise liners to obtain the same benefits, then marketed their blended Scotch as ‘Round the world whisky’.
Recently an American Bourbon Jefferson and Australian whisky Starward have sent casks on worldwide maturation voyages as promotions. Maybe you can trick Father Time?