I often find myself championing the underdog, which for an Italian, who are prone to switch to winning sides whenever possible, is a rare thing. Possibly I've been too long outside the motherland. Even when it comes to wine I find myself championing causes in the same way that others might might swim against the current. I'm always trying to make people like Madeira, I argue that Fernet Branca is actually very pleasant when you've got used to it, I want everyone to enjoy the delights of vintage port but most of all, I want dessert wines to make a comeback.

A dessert wine, by definition, is a wine that it not fermented out completely, leaving some residual sugar that gives it the sweetness. Just to explain that, the process of fermentation is the digesting of sugar by yeast, which produce alcohol as a by-product. Left alone, the yeast will eventually convert all the sugar in the wine must into alcohol, and leave a dry wine. But wine-makers have some control over this; yeasts won't survive once the alcohol reaches about 16% by volume. So if you start with a lot of sugar the yeasts finish fermentation when there's still sugar left. Alternatively, as in Port, you can add pure alcohol to the still fermenting must, bringing the percentage by volume up to around 16% and stopping the fermentation. That leaves unfermented sugar and you have a sweet, fortified wine.

The most famous, and the most expensive, dessert wines are made from the Semillon grape in the Sauternes and Barsac regions of Bordeaux - Chateau d'Yquem being the prime example. The Semillon grape has the capacity under certain climactic conditions, to undergo 'noble rot', or as the French say 'pourriture noble.' The skins of the grapes are attacked by a fungus which makes them shrivel, losing much of their water content and thus increasing the percentage of sugar in the remaining liquid. Obviously this results in a very much smaller quantity of wine from a given area and accounts for the price of wines made in this way.

When dessert wines are made in other areas and with other grapes the noble rot cannot help the wine-maker. The most common way of achieving the same effect is to partly dry the grapes prior to crushing. This is how Italy's famous 'vin santo' is made, and the Southern French 'vin de paille' get its name from the straw on which the bunches of grapes are laid to dry in the sun. What makes dessert wines so appealing to me is not the sweetness, it's that all the flavours and aromas of the grapes are intensified as the grapes lose water-content. A sip of a well-made dessert wine is like a taste explosion, there's a concentration of the flavour elements in the grapes into the liquid.

Wine of the Week

Brown Brothers Orange Muscat 1999

Increasingly found on restaurant wine lists, this is an excellent dessert wine without any price penalty. Intensely flavoured and appealing to the palate, it's at it's best when drunk with food.

Widely Available RRP £9.99 (half bottle)