In 1963, Glenfiddich was the first to export to the world as a single malt, not as a blended malt. Glenfiddich 15 Years Old Solera Reserve was created by Maltmasters by adapting the Solera system used in sherry barrel aging. The spicy and mellow taste is said to be the result of the alchemy of the "solera bat", and the malt whiskey is aged in three types of barrels: bourbon barrels, new white oak barrels, and sherry barrels for about 6 months. It is born by maturation.