What does ageing wine actually do?

[malcolmfraser]

...and how do I know which wines will benefit from being put to the back of the cupboard for a few months?

I have a gallon of apple wine that's pretty sharp tasting - will it mellow out if I leave it for a while?

Thanks
Malcolm

[MKG]

That's some question, Malcolm.

Firstly, aldehydes form from the breakdown of alcohols, and they in turn break down into esters - and all of that makes the wine smell nice.

Secondly, tannins drop out, reducing the harshness of a new wine.

Thirdly, malic acid breaks down, reducing the bitterness of a new wine. If you're lucky, that happens as a malo-lactic ferment which produces a much softer wine with a bit of the old frizzante on the tongue.

Fourthly, a million and one other things happen (there are some awfully long molecules which find themselves coming into being). Wine chemistry is a long, slow affair and should result in a liquid which is immensely drinkable but which, in a lot of cases, bears little relationship to the starting ingredients.

To age a wine appreciably, it needs to be a fairly heavy one to begin with - i.e. a lot of ingredients were used in its manufacture and it was made to be on the high side when it comes to alcohol content. Light wines, or low-alcohol wines, do not age successfully for very long - a year or so at most. All wines though, heavy or not, reach a point after which they deteriorate. I honestly doubt that even the best of the heaviest of wines is going to improve further after ten years maturation - in fact, it's going to deteriorate.

So, your gallon of apple wine. It will certainly mellow, but whether it will mellow to your taste is an altogether different thing. But there are other things you can do, depending upon the cause of that sharpness. You could, for instance, treat it with precipitated chalk, which would reduce the overall acidity. Or you could quite intentionally brew up a very bland wine to blend the apple with.

Now, how do you know which wines will benefit from maturation? Well, all of them, with the above provisos, will alter in character. The thing is whether you want that character to change. I'm always a fan of tasting a wine and, if I like it, putting it on the "drink now" list. But then I like my wines to have the character of the fruit from which they're made, I like a little more tannin than most people etc. etc. I don't like very acidic wines, so I make sure that the acid content is as low as is safe BEFORE I ferment it.

The best thing you could do is to make up a heavy-bodied wine at about 15% alcohol. Taste it as soon as it's finished and write notes. Put it away for a month, taste it again and add more notes. Repeat that on a monthly basis and, after a year - or even longer - read through all of your notes. You''ll be surprised at the things you've noticed and, while you were at it, you'll have learned a hell of a lot about maturation.

Mike

[The Riff-Raff Element]

That's some question, Malcolm.


Mike

What he says.

In the very great wines that will benefit from aging, once the first stages of molecular breakdown and change are over with, it is the slow modifictaion of the various tannins that builds the character of the wine. Knowing what tannins are going to be in the wine (a reflection of the grape varities, the blend and how/where they were grown) and how they are going to change over time is the skill that can make paople pay hundreds of euros / pounds for a bottle.

Not that I would, mind.

[frozenthunderbolt]

I would also add that if you mature it in a cool place and your wine is over acid, it can cause tartaric acid to crystalise and precipitate out of the wine, reducing its acidity if it is then carefully racked off.

[malcolmfraser]

Thanks (again) for the very helpful reply MKG, and thanks to the others for extra tips.

I'll take your advice and make up a 'test' wine to sample over the next year or so, I might also blend a bit of the apple wine with another light wine to see how that tastes.

Cheers and happy new year!
Malcolm