Does a single malt change in an open bottle? A test.

[Robin Garr]

Time to restock the bar with our favorite nectar, Talisker, the finest (and only) Skye malt.

Now, an experiment: Compare the last ounce in the old bottle with the first ounce of the new. Will several months' exposure to air make any perceptible difference? Conventional wisdom holds that the high alcohol level preserves it, but I've known bartenders who doubt this.

Mary and I will pour for each other, then taste "blind," and see whether we get consistent results. I'll post later, but meantime, let's hear what you think. Both reports on rigorous studies and mere speculation are equally welcome as usual.

If that's your steady malt, expect you will notice some diffs as you are closely tuned to it. Suspect most casual observers.
Exposure to oxygen will change anything in time. Evaporation does things too.

Just a guess, but I would think that there would be a difference but as Hoke hints, only if you were really looking for it. How long had bottle A been opened?

I've had plenty of high quality distilled spirits opened for loooongg periods of time with no immediately apparent degradation of flavor (again absent a side by side).

BTW Skye? Everyone knows proper whisky comes from about 180 miles south of there.

I don't know how you were planning the bind test, but this is what I would suggest... Get someone to pour 3 glasses, 2 of which will be from the same bottle (but you don't know which), and one from the other. If you just have just two it is too easy to "find" differences that might not exist.

[James Roscoe]

BTW Skye? Everyone knows proper whisky comes from about 180 miles south of there.

Islay rules!!!!!

I don't have an authoritative source, but generally speaking oxygen sort of dulls the tastes in both scotch and cognac after a month or so of being opened. Obviously, that's my experience in a warm climate, where non-air conditioned temperatures average between 20-30C. If you have it in a cooler environment, I would assume a longer shelf life. This, incidentally is not just good to remember for home storage, but also if you go to a bar or restaurant where they don't sell a lot of high end scotch and you see a bottle that's almost empty. Chances are the scotch won't be at its best.

They should not, though, turn into vinegar or the like, because as distilled drinks, they don't have the ongoing chemical processes found in good wine.

BTW Skye? Everyone knows proper whisky comes from about 180 miles south of there.

Islay rules!!!!!

Weren't you the guy observed by passers-by the other day who was licking old ashtrays and munching on charcoal briquets?

[Robin Garr]

BTW Skye? Everyone knows proper whisky comes from about 180 miles south of there.

Islay rules!!!!!

Weren't you the guy observed by passers-by the other day who was licking old ashtrays and munching on charcoal briquets?

Actually, Skye is still an Island, it just happens to be a different island. I think Talisker is very much in the spirit of the islands malts, and that's why we like it.

I confess to having more Orcadian rhythms in my Scotch preferences.

I don't have an authoritative source, but generally speaking oxygen sort of dulls the tastes in both scotch and cognac after a month or so of being opened. Obviously, that's my experience in a warm climate, where non-air conditioned temperatures average between 20-30C. If you have it in a cooler environment, I would assume a longer shelf life. This, incidentally is not just good to remember for home storage, but also if you go to a bar or restaurant where they don't sell a lot of high end scotch and you see a bottle that's almost empty. Chances are the scotch won't be at its best.

They should not, though, turn into vinegar or the like, because as distilled drinks, they don't have the ongoing chemical processes found in good wine.

This pretty much matches my experience.

[Robin Garr]

Oops, got away from this and never reported back. We did not do the three-glass tasting, which would have been more rigorous, but for what it's worth, Mary and I came up with similar conclusions in our separate blind tastings: The last of the malt that had been residing in an opened bottle for months had very slightly darkened in color and seemed a little less complex and a little more harsh than the sample from the newly opened bottle, but the differences were all in the micro-millimeter range, at the threshold of perception. If our findings hadn't concurred, I would have doubted that the changes were more than imaginary. But since we independently came up with similar findings and expressed them in similar language, it either supports a real difference or merely indicates that 22 years of marriage has got us pretty much on the same wavelength.

As you reported, there is a slight degradation over the course of several months. And while I do hold onto bottles for several years, the lifespan of most bottles once opened ranges from 30 minutes (party scenario) to 4 months. Occasionally a bottle lasts 6-8 months, and I have one bottle that has been open for almost 3 years - I opened a bottle of Pappy Van Winkle 23 year old for my father's 60th birthday, and we have revisited it for a single shot each year since on his birthday. He'll be 63 in September.

[Robin Garr]

As you reported, there is a slight degradation over the course of several months. And while I do hold onto bottles for several years, the lifespan of most bottles once opened ranges from 30 minutes (party scenario) to 4 months. Occasionally a bottle lasts 6-8 months, and I have one bottle that has been open for almost 3 years - I opened a bottle of Pappy Van Winkle 23 year old for my father's 60th birthday, and we have revisited it for a single shot each year since on his birthday. He'll be 63 in September.

Thanks, Schlomo! Nice story, and speaking as a Kentuckian, a very good way to treat your father indeed!

I asked this question of Michael Urquhart when he was in the shop awhile ago. He said that whisky most definitely changes after being opened, and a professional can discern differences within days of opening. He said that over time, as the level in the bottle goes down, the volatiles that make up the character of the whisky oxidize and tend to flatten out. But he also said that doesn't necessarily mean the whisky has gone bad, just that it has evolved and he wouldn't turn down a dram from an older bottle. BTW, Mr. Urquhart is the Director of Gordon & McPahail, and now also Director of Benromach Distillery.

Sorry I missed the conversation.

I have personally experienced and know that oxidation changes whiskeys exposed to air for varying amounts of time. In fact, some whisky should be exposed to air before you can really taste the nuances.

Feel free to pick my brain on all things single malt scotch. Aside from Shlomo R, it seems like I am the other person here who know a lot about whisky (WAY more than wine).

I've been a single malt lover since my days as a teenager living in Scotland (18-years old and up), and I've long noticed changes in scotch from bottles open more than a few weeks. The freshness definitely drops and the sweetness can become a bit bitter, especially when the bottle is getting low and has been open for years.