Trust me, and suspend what appears to be rationality. In this case, proof is in the smelling and the tasting. We re sitting around the dining table with friends who have an increasing appreciation and understanding of wine, two bottles and an array of gl

Trust me, and suspend what appears to be rationality. In this case, proof is in the smelling and the tasting.

We're sitting around the dining table with friends who have an increasing appreciation and understanding of wine, two bottles and an array of glasses before us. Wine one is poured, first into a conventional small tulip-shaped tasting glass. Comments aren't too favourable, either on smell or taste, with sour and acidic among the adjectives suggested.

The same wine goes into glass two, a much bigger affair, somewhat similar in shape though a little more open at the rim. More sniffing, more sipping, and the smiles grow.

Then comes glass three, another generous one but far more globular than its predecessor. "It's wonderful, a completely different wine," is the astonished verdict of someone who previously shared the general doubt that glass shape could make any appreciable difference to the pleasure of drinking. It was hard to persuade her to let go of the glass, so the experiment could continue with the second wine.

And that too proved the point, that scents and flavours can be very, very different depending on the glass you drink from.

The wines I'd chosen for the experience were both pinot noirs, La Grille 2005 from Saint-Pourcain, just to the south of the Loire (Majestic, £6 or £5 if you buy at least two before September 3 as part of your minimum purchase of 12 bottles), and De Bortoli Yarra Valley 2004 (Oddbins, £14).

The first is fresh and light with a hint of spice amid the crisp fruit, good served slightly cool (and in a large glass) with cold chicken or salads. The second shows De Bortoli chief winemaker Steve Webber's passion for elegant pinot (a few years back he made a fabulous Gevrey-Chambertin) in its depth of fruit, concentration and balance - lovely in almost any glass, but deserving of one which allows its qualities to shine.

Which takes me back to the glasses. I was given a trial set from Austrian innovators Riedel, including those intended for bordeaux and burgundy, more than a decade ago. They must be the most effective press freebie ever, as ever since I've delighted in demonstrating what a difference glass shape and size can make.

Even my husband, more sceptical than most, has been won over.

There is some science behind it: the tongue has four taste zones, emphasising sweet flavours at the front, bitterness at the back, saltiness along the edges and acidity just inside the salt-aware zones.

Pinot noir often has high acidity, so a rounded glass with the appropriate rim directs the wine to the front of the tongue and emphasises its sweetness.

Let Riedel, who started this debate in the 1970s and make an array of glasses for every vinous possibility, expand: "The principle of directing the flow of wine to a particular taste zone makes it possible to match the shape to the grape. By customising the shape of the glass to the characteristics of the wine, one can allow the wine to achieve its fullest expression."

If you drink a lot of different wines, you need a deep pocket for glasses to suit every bottle. But there are compromise collections which can make a big difference to enjoyment. And one of my friends sent a successful begging letter to Father Christmas...

Riedel pinot noir glasses cost £50 a pair (Vitis) or £54 (Grape@Riedel, pictured ) - look on the website, www.riedel. co.uk, for more information. You can buy on-line, or from a raft of stockists including John Lewis, Fenwicks at Brent Cross, Heals, Richard Dare in Primrose Hill and Majestic in St John's Wood and Covent Garden.

Liz Sagues