Ed wrote:I do wonder if anyone has tried the open bottle vs. unopened bottle test with a bottle that had received no special treatment, but had just sat there with a finger or two in the bottom?
Ed, we've all done a little informal "research" on this matter. Just go into a bar that doesn't sell much single malt whisky and look for a bottle on the shelf with an inch or so left in it. When you've made a large enough sample (statistical sample, that is), you'll find that many of these have lost a hell of a lot of zip, flavorwise. In fact, I sometimes make my choice in a bar based on which bottle is the fullest. Still no guarantee, I suppose, but the odds are better. Of course, evaporation will be more of an issue in a bar than at your home, so to be fair, you might want to look for bottles that are closed when not being poured, rather than having pourers on them.
I remember visiting the Lochside Hotel in Bowmore some years ago and noting that they had several drams on the menu at prices of £200 or more--I think one was £500. I could see that several of these bottles were down to a finger or two, and you can only imagine how long they'd been sitting there, given the price. Whether these drams were ever worth that price is arguable, but most certainly anyone who bought those last few drops was not getting what he was paying for. Then again, the rich German or Japanese tourist who eventually does buy a round of the stuff to impress his friends probably gets what he deserves.
I think if I owned a pub, I'd date the bottles when they were opened, and after a certain amount of time, mark them down a bit--probably the opposite of what the Lochside does with their rare malts, but I don't want that last finger sitting there for months, no matter what it is, nitrogen or no. Then again, maybe I'd just drink it.
Given that I've noticed that some bottles have improved some after opening, I think I would be inclined to hold off on the nitrogen treatment until the bottle had been open a while, anyway. And I wonder if it's possible that a whisky with absolutely no exposure to oxygen might go sort of dead, anyway...but that's just idle speculation.