Forty years is a difficult distance for any Scotch, and for an Islay distillery built to feed blends it is a minor miracle that Bunnahabhain has been able to release 40 year olds at all. The distillery's historical role as a filling-malt supplier, coupled with the relative indifference to single malt branding under its earlier owners, meant that a handful of very old casks survived in the warehouses essentially because nobody had got round to using them. The modern range has drawn on this quiet inheritance since the Burn Stewart years.
The 40 year old is bottled without chill filtration and at natural colour, in keeping with the distillery-wide policy established in 2010. Strength has varied across releases but sits below the 46.3% house standard — at this age cask strength is itself determined by evaporation, and the spirit is usually bottled at whatever figure remains after four decades of angels' share in an Islay warehouse. The example at hand is around 41.9%.
What distinguishes a 40 year old Bunnahabhain from the 30 is not more of the same but a shift in register. The density gives way to something more filigreed; the sherry recedes and the spirit's own character — the wax, the quiet salinity, the nutty thread — returns to the foreground. It is not, at this price, a whisky to be drunk casually, and the rating reflects its character rather than any pretence at value. For a particular kind of drinker, on a particular kind of evening, it is unforgettable.
