Some wine producers are reducing alcohol content to less than 9 per cent, while others are topping 14. But who's right?

What do you think is high-alcohol wine? I think of something over 14 per cent abv. I wouldn't think of the kind of wine that's by my side as I write this at an isolated gîte in the Hérault, near the jewel-like village of St Pons de Mauchiens. The wine is the sublimely scented Prieuré St Hippolyte Rosé 2004, made nearby and sold for wallet-busting prices of between €3.50 and €4 (around £2.50). Alcohol: 12.5 per cent. Perfect for the wine, and perfect for me.

But not perfect for some Languedoc vignerons, who have reacted with alarm to the general drop in alcohol consumption among their native market. (As we Britons drink more, the French are drinking less.) One of the solutions they've hit upon is to use a process called reverse osmosis to remove some alcohol from their wines.

Reverse osmosis is a well-established wine technology, used for reducing any ingredient that the winemaker regards as excessive. It's used fairly extensively in the New World, as well as Europe. Bordeaux estates with the requisite readies can shed excessive water from a damp harvest using the same type of technology. Their Californian counterparts are more likely to use it for de-alcoholisation, though they can also achieve the same thing by the old expedient (perfectly legal in some circumstances) of simply adding water.

However, in the Languedoc there is a minor problem with de-alcoholisation: strictly speaking, it is not legal. An article published in Midi Libre late last month, surveying the two sides of the issue, found sympathetic but firm opposition from regulatory authorities: "The process does not form part of the authorised oenological practices appearing in EC regulations." On the vignerons' side there is anger and fear: "If France doesn't want to be left on the sidelines," says François Pugibet of the Domaine de la Colombette near Béziers, one of the vignerons experimenting with alcohol reduction, "it has to open itself up to this type of technique. People no longer want to have their heads spinning when they drink wine." At her property she's been experimenting for four years, bringing the level down to just 9 per cent.

This is an incredibly complicated issue, even without the legal aspects. No one can fail to feel sorry for honest winemakers trying to shore up a customer base that's rapidly disintegrating. No one of good sense can criticise the idea of making good wine at a lower alcohol level. (As long as the wine is good, it must be emphasised. The manufactured low-alcohol wines I've tasted weren't fit for washing potatoes.) And there's too much wine about nowadays that is simply higher in alcohol than is good for anyone.

The pint-sized EC-type bureaucratic purist lurking within me still stops and thinks, "Hang on, isn't this taking technology a little far? Aren't we sacrificing an element of terror, authenticity or fidelity to nature?" But he doesn't talk for long. If you can make equally good wine but with 30 per cent less alcohol, and if that convinces more people to drink the stuff - thus saving one of their greatest pieces of national heritage - then why should anyone object?

If the Languedocien winemakers are frightened of their natural 12.5 per cent, God only knows what they would make of the 14-plus regularly achieved in warmer areas of South Africa. I am generally not a fan of high-alcohol wine, but some people in South Africa know how to handle it. One of those is the extremely talented Marc Kent of Boekenhoutskloof, an iconoclast who follows no orthodoxies except for those laid down by his own convictions. His biggest reds don't recognise any number lower than 14 per cent, yet they have the stuffing to keep the alcohol in its place. Just don't try to sell them in Béziers.

Top Corks: Boekenhoutskloof over-14s

Porcupine Ridge Syrah 2004 (£6.99, Avery's Mail Order, Waitrose, Somerfield, Wine Society) Big alcohol is matched by the right figures elsewhere. More northern Rhône than Antipodean.

Porcupine Ridge Merlot 2004 (£6.99, Oddbins) This Porcupine is a lot more interesting and prickly than many of his dumber, cuddlier brethren. Careful oak treatment, pleasingly plump.

Porcupine Ridge Cabernet Sauvignon 2004 (£6.99, Sainsbury's) More French classicism from South Africa, all cassis and fine French oak. And, like all these wines, it has a screwcap - hooray!