I RECENTLY OPENED AN elderly bottle of Domaine de Trévallon, one of the top wines of Provence, from the 1989 vintage. It was drinking beautifully, a lovely elegant wine if fading a little. The level of alcohol read 12 per cent. The current 2007 vintage weighs in at 14 per cent. Such increases are not uncommon. A friend recently brought a bottle of 1990 Henschke Mount Edelstone Shiraz that was 12 per cent alcohol, and tasted wonderful. The same wine from 2002 in my cellar registered 14.5 per cent. In virtually every wine region, alcohol levels have been steadily moving upwards for the past 20 years.

There are a number of reasons. Global warming plays a role, as most of the world’s wine regions are hotter. Improved viticulture and lower yields mean grapes have more concentration, but also more sugar. As the sugars ferment into alcohol, so the wines will have higher levels. But it appears the key factor could be our changing tastes.

We are apparently the Coca-Cola generation, used to sweetness in everything we drink. Even if our wines are dry, we like them to be ripe and have what is referred to as fruit sweetness. In the past, producers in the cooler climates of Europe struggled to achieve full ripeness, and as a matter of course added sugar to boost alcohol levels, a process known as chaptalisation. Grapes were picked solely on sugar content.

However, in recent years a second factor, that of physiological ripeness, has entered the winemaker’s lexicon. They now believe that the phenolic ripeness of grapes is of equal importance. It is this physiological ripeness that gives a fruit ripeness or sweetness to the wine.

In cooler climate wines, physiological ripeness normally occurs before sugar ripeness. But in warmer regions it occurs later, and most New World winemakers now give their crop a much longer “hang-time” on the vine to obtain fully mature grapes. In Chile, for example, many wines were criticised for having herbaceous or leafy green flavours, the result of early picked-grapes. They were usually around 12 to 12.5 per cent alcohol. Most now harvest much later to avoid this. The wines are now typically 13.5 to 14 per cent and often more.

Is this extra alcohol a problem? For those who like rich, powerful wines, obviously not. But I like to drink quite a lot of wine; not because I want to get drunk, but because wine is a gustatory pleasure, and the higher the alcohol, the less I can tolerate. A bottle of alcohol at 15 per cent has 25 per cent more alcohol than one at 12 per cent – worth remembering if you are counting units. For example, 250ml of wine at 15 per cent is four units, the entire recommended daily intake for males.

Higher alcohol levels also change the way a wine tastes. The nose becomes less focused and on the palate, it can be very blowsy and hot. By contrast, I find lower alcohol wine refreshes the palate and stimulates the appetite. I may be in a minority. At public tastings I have done, it is invariably the wine with the highest alcohol, ripest fruit (and frequently the most oak, too) that appears to be the most popular. Perhaps I need to re-educate my own palate. However, I have noticed a change in the past year or two, with wine-drinkers preferring the lighter style.

It is not always easy to work out a wine’s strength. The alcohol on the label does not have to be entirely accurate. The producer is allowed a half a percent margin of error in either direction. An Australian winemaker recently told me that in Europe this has now increased to .8 per cent, which means that wine that claims to be 13 per cent could be almost 14 per cent.

BOTTLES OF THE WEEK

Domaine La Condamine L'Évêque, Syrah Mourvèdre 2009, Côtes de Thongue, 12.5%, €9.99Light, savoury, dark fruits with a nice acidity and no tannins. Great for midweek drinking. Stockist: O'Briens

Domaine Uby Colombard-Ugni Blanc 2009, Vin de Pays des Côtes de Gascogne, 11.5%, €9.99You would be forgiven for thinking this was a Sauvignon, as it tastes very like one. A fresh, lifted, aromatic nose leads on to some very attractive rounded peach and passion fruit, held in check by lively lime acidity. Perfect party fare, or with fish and seafood. Stockists: Deveney's, Dundrum; Marlay Wine Shop, Rathfarnham; Molloy's, Donnybrook; The Vintry, Rathgar; The Vanilla Grape, Kenmare; Ardkeen Stores, Waterford

Riesling Réserve 2008, Caves de Turckheim, Alsace, 12%, €13.99Fresh and clean, with subtle pear and honey fruits. This is a delicious wine that will go perfectly with fish, chicken and pork dishes. Stockists: Savage's, Swords; Lilac Wines, Dublin 3; Select Londis stores; Gerry's, Skerries

Château Bellevue la Forêt 2006, Côtes du Frontonnais, 13%, €11.95This has a wonderful nose of forest fruits, and on the palate it is full of black pepper and blackberries. Very moreish, with an enticing freshness on the finish. Definitely one to have with food. Stockists: Widely available, including Superquinn and select Londis; Molloy's Liquorstores; Swans on the Green, Dublin 2

BEER OF THE WEEK

Youngs Bottle-conditioned Bitter, 4.5%, €2.89 for a 500ml bottleVery moreish light ale with a fresh hoppiness and a dry, slightly bitter finish. Good session beer or with sausages.

DIARY DATE

Superquinn is holding a tasting with Dominique Grangeon of leading Rhône producer Domaine de Cristia on October 13th in its Lucan store. There is no charge, but numbers are limited. Apply for a space at wine@superquinn.ie