The Big Question: So does French wine still deserve its reputation as the best in the world?

Does the US's victory over France in a 'blind tasting' of wines matter?

It matters much less than the American triumph that this week's tastings were intended to commemorate: the so-called "Judgement of Paris" of 1976. Then, leading wine tasters, including French ones, placed top Californian reds ahead of the finest French clarets for the first time. That result shook the French industry to its roots.

Depending on your viewpoint, or tastebuds, the 1976 shock transformed the top of the French wine industry, for the better - or the worse. It certainly forced the complacent French top producers to raise their game. Some purists argue that it also began a process of "Americanisation" of some of the leading Bordeaux wines.

In any event, 30 years on, everyone with any sense, or taste, accepts that there are excellent wines from California, Australia, Spain, Italy, Germany - not just from France. On the other hand, in terms of sheer variety, and quantity, of its leading wines - from Bordeaux and Burgundy and elsewhere - France is still far ahead of all other countries.

But which wines are the very best?

It is all a question of taste. Even within France, wine lovers will come to blows (almost) over the relative claims of Bordeaux and Burgundy wines.

This week's tests, flagged long in advance, had an air of inevitability about them. Suffice it to say that American, and British, wine connoisseurs still flock to buy the best French names.

On a blind tasting of vintage bottles from individual producers, Californian wines might easily win on a given day. On another day, French wines might win, depending on who the tasters are.

This week's tastings were between Californian and Bordeaux cabernet wines, or clarets. Burgundy fans might point out that the most expensive of all red wines is neither of these, but a Romanée Conti red burgundy made from pinot noir grapes in a vineyard about the size of a football pitch.

At the top end of the market, it is all a bit meaningless. If you are paying £100 for a bottle of wine, you ought to know what you like and what you are paying for.

So how are the top French wines faring?

Absolutely corking, thank you. Champagne, of all types, cannot be grown in sufficient quantity to meet the booming world demand. The leading châteaux in Bordeaux, and the grand and premier cru labels from Burgundy, have no problem in selling at inflated prices.

The silly money prices of the late 1990s, fuelled by speculation on wine futures, have calmed, but you would still expect to pay about €40 to €100 (£27 to £68) a bottle for the excellent 2005 vintage from a top Bordeaux château.

By the time the wine is ready to drink, five or so years from now, those prices will have doubled or trebled.

There is not one French wine industry, there are two or three. The crisis is real enough, but it affects the middle market (the kind of wine that you might buy for a Friday night dinner at home) and the bottom of the market (the stuff sold in cardboard canisters and plastic bottles).

Here, French wine growers have been hit by a double whammy. The French, especially the young, no longer drink as much wine. Domestic consumption is less than half of what it was in the 1960s. At the same time, foreigners are turning more and more to so-called New World wines, especially Australian labels, which they find more reliable and easier to recognise.

You may have liked the Bordeaux you bought last week, but which of the 30 different châteaux in the shop was it? A wine called Kangaroo Creek, or whatever, is easy to remember. There are 466 different AOC, or Appellations d'Origine Contrôlées wines, in France, before you even start with the Vins de Pays and the hundreds of Bordeaux châteaux.

Ten years ago, France had 33 per cent of the British market in still wines. That is down to a little more than 20 per cent. For the first time in the past two years, something unthinkable has happened. France has a wine lake, or unsold surplus, not just of rotgut, generic red wine, but of "appellations contrôlée", relatively fine wines, especially from Bordeaux and Languedoc. France is still the largest exporter of wine, by value, in the world, but exports of non-sparkling wines fell 2.5 per cent again last year, the fifth successive year of decline.

What are the French doing about it?

Quarrelling among themselves mostly. Last month, the government produced a plan which would encourage fewer, simpler and more readily recognisable brand names for some middle- and low-market French wines. It would also allow French producers to flavour their wine with oak chippings, as the Aussies do. Both these ideas are heresy to the purists.

Quarrels apart, it is inevitable that middle-market French wine will drift away from France's traditional "location", or appellation, based system and towards a simpler, New World-type mass-marketing of cheerfully labelled wines based on the "noble" grape varieties, such as Chardonnay or Merlot, or Cabernet Franc or Sauvignon Blanc. This is being resisted by many small growers.

French philosophy holds that wine comes from the soil - the terroir, or special soil, terrain and weather conditions of a particular vineyard - not just from a grape variety and not from a factory. This philosophy is fine at the top end of the market, and is applied in California and Australia as much as in France. It can create little-known jewels in the middle market. It can also act as an excuse for bad wine-making.

In the mass-marketing age, the plethora of individual French wines in the middle market has become a handicap, rather than an advantage. In years ahead, whether it likes it or not, the French middling wines will have to abandon, in part, the French terroir ideology and tradition.

Many small producers, to survive, will have to stop making their own wines. Instead, they will sell their grapes to big wineries, which, as in Australia or the US, will mass-produce wine of reliable quality and taste. The French growers - and many wine lovers - detest this notion. It would reduce many producers to "grape farmers". It would ruin the fascination of finding that special "little" wine that no one else knows.

Do the French import much wine themselves?

Very little, although that is changing slowly. You can find Italian and Spanish wines, and some American wines, in specialist shops. In supermarkets, wine shelves tend to be all French, save in Calais where they slavishly cater for the British taste.

Is it true the French 2005 vintage was superb?

Everyone says so, especially for Bordeaux wines, especially for Bordeaux red wines and, to be very precise, especially for the Médoc and Haut Médoc clarets, which use a lot of Cabernet Franc grapes. Weather conditions for wine were excellent across France last year - dry but not too dry; warm but not too warm - and especially good for the Cabernet Franc vines in the Médoc. Some say that it may be the finest Médoc claret vintage ever. As a result, sales of all Bordeaux - including the middle-market and low-market Bordeaux - are booming. But, that alone, will not solve the deeper crisis in French wine.

Should you still buy French wine?

Yes...

* The French producers still make among the very best, but you have to know what to go for

* There is no better way to recall the tastes of that splendid holiday along the Rhône

* You can get good value, middle-market wines, as many of the New World products fetch premium "fashion" prices

No...

* As the Berry Brothers' blind tasting showed, you can get equally good wines from both Old and New World sources - why limit yourself?

* The New World wines, sold by variety rather than vineyard, provide a more consistent product

* If you want to buy very cheap wine, Spanish or Italian is better