Man – or woman – walks into a bar.
A certain kind of bar. One that prides itself on having anything up to several hundred whiskies for you to pay an arm and several legs for. The kind that that offers a ‘whisky menu’ and advises on flights, food combinations and general connoisseurship daftness.
Take a wee look at the bottles. How full are they? Because the great ignored fact about such establishments is this: whisky goes off in an open bottle.
True, some bars recognise this and hand-date the opening of a particular whisky, often selling it off cheap after a set length of time – notably the Highlander in Craigellachie and Fiddlers in Drumnadrochit. Some – very few, and none that I’ve ever had a dram in – use a nitrogen pump to fill bottle after a measure has been poured, or a Vacuvin to extract the air. Most denigrate the entire idea that strong drink deteriorates.
However, the science of the matter seems indisputable. I have been told that the maximum shelf life of an opened bottle of average whisky is two years. Deterioration gets worse the emptier the bottle gets, as there’s more air inside the glass, but you aerate the whisky every time you pour. Alcohol+water+oxygen = (in the end) acetic acid.Not to mention all those other compounds, the ones that give each whisky its own special flavour, evaporating at different rates.
There are tricks you can play. For example, glass marbles, like the ones used by flower arrangers to fill vases, in the bottle to keep it filled to the neck. I have tried this and found it irritating and ineffective. Not to mention the fatal mistake I made by washing the balls and then failing to dry them properly, which left enough water attached to dilute the lovely Benromach http://www.benromach.com/benromach.htmlin to unacceptability.
My concern about this came about after I tried a Scotch Malt Whisky Society Mortlach, with maybe a couple of inches left in the bottle after five years, which had become, to put it mildly, rancid.
I spoke to Master of Malt John Lamond, a man much more experienced in whisky matters than I will ever be and someone who has a background in the wine trade too. He pointed out that alcohol plus oxygen equals acetic acid, and there’s no running away from that basic scientific fact. It’s worse with wine. John no longer orders sherry in bars, he told me, as the maximum shelf life of an opened bottle of sherry is just three days. Port, a week. Whiskies last a great deal longer, due to the alcoholic strength, and some will last longer than others – some congeners/alcohols distinctive too particular distillates evaporate quickly, others slowly.
So the next time you see rare whisky for sale behind a bar, think carefully about the state of the bottle before you spend your £20 for 35 ml. Or even your £2.50. The case for that old maritime habit of gathering a group of friends, cracking a fresh bottle and throwing the cork away seems…well. Open and shut.