I asked myself this question while drinking from an old bottle of Glen Marnoch Speyside Single Malt.
Back in 2018 I reviewed this whisky.
It didn’t particularly suit my palate – I found the added caramel a bit heavy & ‘muddied’ any potential flavours the Speysider possessed.
4 years down the road – long past the 2 years maximum storage recommendations for an opened bottle – I dug it out from the back of my spirits shelf.
This time round I experienced a subtle hint of what I can only describe as ‘burnt’ coming through.
Could this be the caramel degrading?
If anything – age has improved this Glen Marnoch!
I found this ‘burntness’ a far more attractive quality than the rather sweet & sticky caramel experienced with the fresh bottle.
Still wouldn’t rate it however.
Web article on storing your open spirits bottles here.
Original Glen Marnoch blog here.