Making a good wine is like a singing a harmony. On one end, there needs to be acidity and a slight bitterness that comes from the tannins. Then there's the alcohol content — the bit that envelopes the wine in warmth and imbues the liquid with a burst of fruitiness. Sweetness is the final flourish that balances this all out.
Sweet wines are made using different techniques, but as with all wine, the process begins by exposing crushed grapes (or “must”) to yeast, which feeds on the fruit’s sugars and creates alcohol in the process. Impede the yeast along the way, and some of the grapes’ sugars will remain in wine — residual sugar that gives sweet wines their flavour profile.
But things get complicated from there. Sweet wines are made from white-wine grapes stricken with botrytis. If conditions are right, this desirable fungus (fittingly called noble rot) takes hold in vineyards at the tail end of harvest time. This saps grapes of half their water content, causing the fruit to shrivel and concentrates its sugars.
Certain weather conditions such as morning humidity and warm sunny afternoons also act as a rot-control system, creating an environment in which yeasts can only survive so long and residual sugar builds up. Botrytised wines are made most famously in places like Hungary’s Tokaj area — the technique was pioneered here in the 17th century —and France’s Sauternes, in the Bordeaux region. These wines offer a pleasantly musky earthiness that lends a particularly savoury flavour.
But things get complicated from there. Sweet wines are made from white-wine grapes stricken with botrytis. If conditions are right, this desirable fungus (fittingly called noble rot) takes hold in vineyards at the tail end of harvest time. This saps grapes of half their water content, causing the fruit to shrivel and concentrates its sugars.
Certain weather conditions such as morning humidity and warm sunny afternoons also act as a rot-control system, creating an environment in which yeasts can only survive so long and residual sugar builds up. Botrytised wines are made most famously in places like Hungary’s Tokaj area — the technique was pioneered here in the 17th century —and France’s Sauternes, in the Bordeaux region. These wines offer a pleasantly musky earthiness that lends a particularly savoury flavour.
In Sauternes and Barsac along the Garonne river, noble rot finds sanctuary amongst the vineyards of classic white wine grapes Semillon and Sauvignon Blanc. Here, too, is the fabled Chateau d’Yquem, its sweet botrytised wines capable of aging for decades. But even when young, Chateau d’Yquem vintages are the epitome of what river-borne morning mists can do to grapes. The wines taste of apricot, peach, and mushroom, with a mouth-filling suppleness scored by a tingling acidity. One classic pairing is foie gras, while mushroom dishes and blue cheeses are also excellent pairings for the less meat-inclined.
Also not to be overlooked: botrytised wines of increasing levels of residual-sugar, from demi-sec to the rarer bottle-aged moelleux, all made of Chenin Blanc grapes from Vouvray in the Loire River valley in northwest France. Vouvray wines are known for their bracingly-high levels of acidity—a powerful counterbalance to sweetness. They also boast honey-like and lemony aromas that are most accurately described as funky. From cream sauces to sausages to artichokes, most foods pair well with Vouvray wines.
Also not to be overlooked: botrytised wines of increasing levels of residual-sugar, from demi-sec to the rarer bottle-aged moelleux, all made of Chenin Blanc grapes from Vouvray in the Loire River valley in northwest France. Vouvray wines are known for their bracingly-high levels of acidity—a powerful counterbalance to sweetness. They also boast honey-like and lemony aromas that are most accurately described as funky. From cream sauces to sausages to artichokes, most foods pair well with Vouvray wines.
The sugar concentration that produces sweet wines are also malleable by human hands. When nature doesn't do the trick in ripening the grapes, harvested grapes are placed in the sun or special drying rooms before being crushed, as is the case with northeast Italy’s recioto wines.
There’s yet another way to stop yeast from gobbling up sugar: During fermentation, add a little spirit — any liquid with an alcohol percentage of 16 and above — and all sugar-alcohol conversion will come to a halt. In France, these wines are known as vin doux naturels (natural sweet wines) and are commonly enjoyed in the country. Best enjoyed with hearty fare such as caramelised mac and cheese with barbecue-style pulled pork.
There’s yet another way to stop yeast from gobbling up sugar: During fermentation, add a little spirit — any liquid with an alcohol percentage of 16 and above — and all sugar-alcohol conversion will come to a halt. In France, these wines are known as vin doux naturels (natural sweet wines) and are commonly enjoyed in the country. Best enjoyed with hearty fare such as caramelised mac and cheese with barbecue-style pulled pork.
This article first appeared on Robert Parker Wine Advocate in March 2017. Click here for more stories from Wine Journal.
