Dry Chenin, the Loire's new weapon

Leaning into the wind whistling straight off the Atlantic 80 miles away on to his own particular south-west-facing butte of the Bonnezeaux appellation in the Loire Valley, Bernard Germain told me proudly, "In 1996 when I bought Château de Fesles all my neighbours in Bordeaux laughed at me. They were all investing in Argentina at the time. But thanks to global warming, our time here has come."

Global warming seemed a distant prospect last month when I can see from the scrawl in my notebook that I must have been wearing gloves when I took down his words, but he has a point. One of the main things that has so far held back many wines of the Loire Valley in comparison with the fruit bombs of the New World has been its relatively cool climate and the fact that many grapes there in the past had obviously failed to ripen fully. But if average temperatures everywhere are set to rise, then the Loire Valley's wines will be clear beneficiaries, as some stunning reds from 2002 and heatwave vintage 2003 so eloquently demonstrate.

In the old days reds in two years out of three were thin, weedy and tart but in future should settle nicely this side of ripeness most years while the white wines for which the Loire is most famous are already much riper – naturally riper rather than thanks to the beet sugar once added routinely to bump up alcohol levels. The average total acid level in Muscadet for example has fallen from more than five grams per litre to a level closer to three.

Climate change has played some part in the recent improvement in wine quality in the Loire but arguably more important has been man's role in the cellar and vineyard, particularly vineyard. Today among conscientious growers there are real efforts to maximise flavour and minimise the likelihood of mildew and the rot to which the local white wine grape Chenin Blanc is so prone by fierce pruning, de-budding, thinning the vine canopies, grassing over vineyards so that less water is available to the vines which are therefore less leafy and produce grapes which can be kept on the vine longer and are naturally riper. The really conscientious producers (still a minority but a growing one) are careful to pick by hand, often going through the same vineyard several times to pick only those grapes at optimum ripeness each time, rather than a single scalping by machine, and are motivated by quality rather than quantity.

In the cellar the big difference is that sugar beet and sulphur are used so much less. In the bad old days a typical Vouvray, for example, reeked of the spent match smell of sulphur because it was an easy way to ensure that a wine full of added sugar would not re-ferment.

"I started making wine with my grandfather in 1978," says Jo Pithon, now arguably Anjou's most lionised producer. "I tell people, I know all about bad wines – I used to make them. In those days we bottled with 125 milligrams per litre of free sulphur. Now I aim for 25 and a sterile bottling."

Two of his Anjou Blanc Secs, dry wines made from Chenin Blanc, a grape dismissed as irredeemably cheap in places such as South Africa and California, typify the recent wine revolution here. His Bonnes Blanches vineyard of schist and clay in St Lambert used to produce sweet wines but the old vines here are now dedicated to producing a spicy, powerful dry white wine with (occasionally too powerful) oak influence – a thoroughly modern wine in fact.

This is the big development, that the producers of the middle Loire – Anjou-Saumur and Touraine – realise that the future of their signature white wine grape Chenin Blanc will depend on their ability to produce fine dry wines from it, and oak has played a crucial role in this transformation. The majority of growers were up in arms when the likes of Jacky Blot of Domaine de la Taille aux Loups in Montlouis across the river from Vouvray and Bernard Germain of Fesles started to ferment the local Chenin in new oak barrels, typically keeping the new wine on the lees. But even I, deeply suspicious of over-oaked wines, have to compliment them and those like them who are now producing dry Chenins of enormous sophistication and depth thanks to the extra layers of flavour and richer texture resulting from the stint in oak. The 2005s in particular are extremely promising.

It was of course necessary to experiment with exactly what sort and size of barrel worked best and most producers seem to favour the 400 litre size, much larger than the norm in Bordeaux and Burgundy, for this relatively delicate grape.

The relatively tiny Jasnières appellation in Coteaux du Loir pioneered dry Chenins via the likes of the fashionable Eric Nicolas (imported into the UK by Richards Walford), de Rycke (Irma Fingal Rock) and Joel Gigou but these wines have an austerity that is unlikely to convert neophytes. Mark Angeli (Yapp) of Anjou has also won friends for his quirky wines, including many dry Chenins, within France anyway and also depends heavily on oak.

On the other hand, some of the most dazzling red wines I tasted on a recent visit to the middle regions of the Loire had seen no oak at all. If Chenin Blanc is the signature white wine grape of this part of the wine world, Cabernet Franc is its red counterpart. Cabernet Franc makes more delicate, more fragrant and typically softer wines than its progeny Cabernet Sauvignon. Since 1994 the talented winemaker Philippe Vatan of Château de Hureau has used a delicate hand with oak on his Saumur Blanc Sec but his various luscious bottlings of the red Saumur Champigny show wonderfully precise variation in terroir influence without any oak at all because, as Vatan puts it, "oak dries the tannins on the finish, especially during the first two years, and I don't like it".

If and when wine drinkers tire of the massive alcohol levels and extreme concentration of so many wines made in hotter climes today, the Loire should be well placed to take advantage of this trend. But those selling the delicate wines of the Loire outside France have encountered difficulties because the wines are so different from what has been the fashionable norm – and have been perceived as poor value. To a certain extent producers in the Loire have been sheltered from the harsh competitive realities of the international wine market by their proximity to Paris. When so many Parisians regard the Loire as home, or at least home at weekends, wines such as Saumur-Champigny and Bourgeuil are extremely easy to sell in and around the French capital.

Outside France, red Chinon has a certain following in the US – perhaps partly because of its easy-to-pronounce name, but most importers of Loire wines agree somewhat glumly that consumer interest in Loire wines tends to begin at Sancerre and end at its close neighbour and taste-alike Pouilly Fumé, both towns many miles upriver of Anjou-Saumur and Touraine. These two aromatic dry whites based on Sauvignon Blanc continue to be extraordinarily popular and sell almost regardless of quality. But Sauvignon Blanc is by no means as important to the Loire Valley as Chenin Blanc is.

As Bernard Germain admits, "Chenin Blanc can make the worst and best wines in the world, but we have to find a market for them – too few people know about great Chenin Blanc."

Rich and smoky on the nose from a difficult year. The wine needs another year or so to show at its best.

Domaine Huet, Le Mont 2004 Vouvray Sec

Biodynamic wine with enormous life and tingle.

Incredible that this is 14.5 per cent – it doesn't taste it. Very lively and zesty.

Vines are 55 years old – very intense and youthful. Intense though slightly severe on the finish.

From an excitingly steep vineyard painstakingly acquired parcel by parcel and replanted for the first time in decades.

Powerful, rich but dry, hints of lime.

Claude Papin, Château Pierre Bise 2004 Savennières

A good example of the current revolution in this once-excessively-austere appellation. Full, clean and approachable.

As usual from this quintessential biodynamic domaine, seriously weird nose but impressive extract and no shortage of interest.

Ready to gulp. Open and layered – very full and unusual.