Sweet and sparkling wines: two different qualities

Sweetness has several routes

There are several ways to make sweet wine. High-sugar grapes can leave sugar after fermentation; fermentation may also be stopped, while permitted sweetening is another option for some wine categories. Grape sugar can become concentrated through extra ripening, drying, noble rot or separating the water that has frozen inside the grapes. Sugar remaining after fermentation is called residual sugar.^[1]

Fermentation can be stopped by filtering out yeast; in very sugary must, yeast may not consume all the sugar. Some wines can also be sweetened with grape must, concentrated must or sweet wine.^[1]

What does noble rot mean?

Under suitable conditions, the fungus Botrytis cinerea causes grapes to lose water and their components to become concentrated. This noble rot is important to some sweet wines, including Tokaji Aszú. Botrytis is not always beneficial: the ripeness of the grapes and the weather are crucial.^[2]

When tasting sweet wine, consider acidity, alcohol and aromas alongside sugar: together they shape the sense of balance. With Tokaji Aszú, understanding the style therefore means considering its acidity as well as its sweetness. It is useful to explore the wine on its own before choosing food for it.^[2]

What changes with bottle or tank fermentation?

During fermentation, yeast converts sugar into alcohol and carbon dioxide; retaining the gas creates bubbles. The presence of bubbles therefore does not, by itself, indicate how sweet the finished wine will be.^[3]

In the traditional method, a base wine undergoes a second fermentation in bottle, retaining the carbon dioxide produced. Time on the lees can shape aroma and texture. In the tank method, second fermentation takes place in a pressure-resistant tank, often with an emphasis on fresh fruit character. These are common approaches, but they do not cover every way of making sparkling wine.^[3]

Bottle and tank fermentation should not become an automatic quality ranking. First establish the style we want, then assess the wine against that preference. A single aroma or the appearance of bubbles is not proof of the method; the producer’s information can confirm it.

Read “dry” in its label context

In Champagne, dosage after disgorgement is one step used to establish the final sweetness. The extra dry category allows more sugar than brut, and sec is sweeter again. Dry or sec on a sparkling label therefore cannot simply be read as the equivalent of dry still wine.^[4]

Dosage is usually a mixture of wine and sugar, with its amount chosen for the intended style. It is added after second fermentation and disgorgement. Establishing the final sweetness and creating bubbles are therefore separate steps: a sparkling wine can be both distinctly fizzy and dry-tasting.^[4]

Start with two questions

When hosting, begin with your guests’ preferences and the food you plan to serve. Do not let the formality of the occasion alone decide between a fresh, fruity sparkling wine and a more developed example. A sweet wine can also be tasted on its own. You do not have to design a separate dish for every bottle when the aim is to understand the wine itself.