What do you think what alters opened whisky during time?

[lbacha]

Evaporation is only going to occur if you leave the bottle open for an extended period of time or you have a faulty seal, oxidation will occur even in a completly sealed bottle so i'm going with oxidation.

Len

[Deactivated Member]

But the whisky doesn't change if the bottle remains sealed. In the experiment Muskrat Portage conducted, in which he left a dram out for 24 hours, the results were exactly what people describe happening to a bottle that has been open for a long time. Every time you open and pour, you let some vapors out, and some fresh air in. Over a long period, the result is the same. It's especially noticeable in bottles left on a bar with open pourers.

[Drrich1965]

But the whisky doesn't change if the bottle remains sealed. In the experiment Muskrat Portage conducted, in which he left a dram out for 24 hours, the results were exactly what people describe happening to a bottle that has been open for a long time. Every time you open and pour, you let some vapors out, and some fresh air in. Over a long period, the result is the same. It's especially noticeable in bottles left on a bar with open pourers.

Do you mean to say that if a bottle was left unopped for a million years, it would not change? If the answer is that it would in this lenght of time, then we are talking perceptable change, degrees, and must figure out the exact amont of times given certain variables (i.e. heat, light, ect).

[Deactivated Member]

Do you mean to say that if a bottle was left unopped for a million years, it would not change?

Of course not. But the question is what the cause of deterioration in whisky is, in a bottle that has been open for a while.

If you open a bottle of wine, pour a glass or two, and then replace the cork, the remaining wine will oxidize in a few days. If this happened with whisky, we'd all have a lot of worthless bottles right now. So plainly oxidation in whisky, if it occurs, happens at a much slower rate than in wine. I don't deny that it can occur in whisky, and it may be part of what is going on in a bottle that has been open for a long time. But it seems obvious to me that whiskies I've had that have been off were suffering from the evaporation of volatile components, as I think Musky demonstrated.

[peergynt323]

I promise I won't argue on this thread. See Evaporative Equilibrium on this Wikipedia article: http://en.wikipedia.org/wiki/Evaporation

[TheLaddie]

The question now is simple, what do you think that alters whisky during time after opening?

The answer is simple.

I drink it.

[Deactivated Member]

I promise I won't argue on this thread. See Evaporative Equilibrium on this Wikipedia article: http://en.wikipedia.org/wiki/Evaporation

Thank you for supporting my position.

[les taylor]

I'm with the Laddie. Once its open what other viable option is there.

[peergynt323]

If you read more carefully, Mr. TH we are now talking about opening and then resealing a bottle of whisky. It's obvious that it doesn't evaporate appreciably, but anyone with a nose and palate will tell you that it changes.

[lbacha]

Evaporation is an easy thing to measure since we are talking about the alcohol evaporating. Other than water (and it will evaporate much slower than the alcohol) most of the other elements and compounds won't evaporate out at room temp. I suggest we find someone who can measure alcoholic content (Any brewers or winemakers on the forum) and leave a bottle of say gin or vodka open for a week or two (I can't rationalized experimenting with a good bottle of whisky) then check the alcohol content it should be lower than the original content due to the evaporation of alcohol. If it isn't then oxidation is our culprit. I think this is a Myth Busters question for anyone who has seen that show.

Len

[peergynt323]

The abv would be lower, but both water and alcohol are scentless and tasteless. The question is really whether the appreciable change in the aromatics and flavor components evaporate or oxidize, and unfortunately that cannot be proven easily. Does anyone have a spectrometer handy?

[les taylor]

Peergynt wrote:-

Does anyone have a spectrometer handy?


Sorry no but I do love Myth Busters a great show.

[Deactivated Member]

If you read more carefully, Mr. TH we are now talking about opening and then resealing a bottle of whisky. It's obvious that it doesn't evaporate appreciably, but anyone with a nose and palate will tell you that it changes.

Disagreed (part in bold).

The abv would be lower, but both water and alcohol are scentless and tasteless. The question is really whether the appreciable change in the aromatics and flavor components evaporate or oxidize, and unfortunately that cannot be proven easily. Does anyone have a spectrometer handy?

Agreed. Let's leave it at that.

[Muskrat Portage]

C_I:
An interesting twist on what appears to be an age-old discussion, at least in this forum.

Despite the proposals made by my learned friends, I choose to go with "oxidation" as the effect which affects whisky over time. To state it simply, whether the bottle is opened or sealed, oxidation naturally will take place. There is always air in the necktop of any bottle which will, over time, affect the surface of the liquid and thereby the sum total of the product.

Once said bottle is opened and a pour of liquid done, there will be a greater area of the liquid surface in contact with a greater volume of air. Logically, this increase of surface area will mark an increasing of the rate of oxidation over any previous rate.

In conclusion, once a bottle is opened, it is best just to drink it and enjoy it preferably in convivial company. To stave off the long term effects of oxidation of course.
Muskrat

[Di Blasi]

I chose other, as all of those choices apply, plus others, I'm sure. One, for example, is the drinker, yes you, that have changed tasting styles, moods, etc. Whisky changes over time, yes, in and out of the bottle.

[Aidan]

Is there any point guessing what happens. If the handle on my spectrometer wasn't broken, I'd be able to tell you exactly.

Anyway, I might as well have a guess too. I think whisky would have undergone a large amount of chemical activity during production and maturation. So this might mean it has found a chemical equilibrium. The way air acts on this may either oxidise, reduce or do nothing to the whisky.

[irishwhiskeychaser]

Well I voted 'Evaporation leading into oxidation'

As the less you have in the bottle the quicker it seems to go off and that is probably because you have more air in a nearly empty bottle than a nearly full one.

Hey Aidan that's funny as my Hi-Flux-Capacitor is on the fritz too.

Between the 2 of us we could of cracked it but only for the dodgy hardware

[Scotchio]

Without entering into this debate at all I will mention something that may be relevant, A recent mini of Littlemill 8 I picked up contained about 2cl of whisky. It was an error on the sellers part and he reimbursed me appropriately. The bottle was sealed so i figured I'd give the contents a try anyway. The liquid was not whisky but pure water, it was bottled at 40% and the angels had sucked their greedy share right through the cap. clearly, like many on this forum they prefer their whisky without water. water

[peergynt323]

I like your scientific mind C_I. Also note that gold and copper probably have enormous boiling points but a distinctive smell. It depends on how sensitive our nose is to those things. Sharks can detect blood on the order of molecules.

Where did you get such an accurate scale, C_I? It wouldn't have anything to do with you living in the Netherlands, would it?

[Lawrence]

But the whisky doesn't change if the bottle remains sealed.

You've obviously never heard of Old Bottle Effect; people who make a practice of collecting and sampling older whiskies (those whiskies that have been in the bottle for decades) comment on a common taste characteristic which they have termed Old Bottle Effect.

Whisky does change in sealed bottles, remember bottles and the closures are designed for short term storage; they are simply not sesigned for the long term and air enters and alcohol leaves in some cases.

But then again you don't believe in Scottish terroir either.

[Deactivated Member]

How long does it take to be noticeable, Lawrence? I'm talking about bottles on the shelf for a normal amount of time in a shop, or even for some years at home. You are talking about very old bottles, I take it. As we all know, whisky is not considered to age in the bottle the way wine does.

No, I don't believe in terroir in whisky production, or the tooth fairy, either. Tales told to stimulate the imagination of the innocent.

[lbacha]

I've noticed what Lawrence is talking about in alot of 1960's bottlings (that is bottled in the 1960's), I attributed it to when it was bottled but maybe it is what happens while in a bottle for that long, remember wine oxidizes through the cork so why not whisky but at a slower pace because of the higher alcohol content.

[peergynt323]

I have to agree with Len and Lawrence. Saying that whisky doesn't change after 30 years in a sealed bottle is much like saying that whisky doesn't change within a year of opening the bottle. It does, just not that much.

Malt maniac Serge often talks of bottle age. Also I had the priviledge of trying a Linkwood bottled in 1971 with a screwcap and that was one elegant whisky. I don't have much experience with this kind of thing, but it was like nothing I had ever tasted. And even the old bottles of Tamnavulin and Dufftown were fascinating because they were so damn smooth.