Demystifying Sugar Levels in Wine
Learn everything about sugar levels in wine, from its transformation during fermentation to its role in flavor balance. A focus on Quebec wines and the myths surrounding sugar in the bottle.
Many people focus heavily on sugar levels when choosing a wine from the shelves. But what is the real impact of sugar in wine? Let’s dive into the bottle to debunk the myths surrounding sugar levels in wine.
First, it’s important to know that Quebec wines contain very little sugar. Most analyses show sugar levels of two grams per liter—virtually undetectable. In comparison, commercial grape juice contains 152 grams of sugar per liter.
This isn’t because Quebec wines are vastly different from others in this regard; it’s primarily because almost all the sugar is converted into alcohol during fermentation. Yeasts “consume” the sugars, transforming grape juice into wine. No sugar means no alcohol!
Sugar is therefore essential and an integral part of wine production.
“Glucose and fructose accumulate in the grape as it ripens,” explains Dominique Fink, president and co-founder of Oenoscience, a laboratory specializing in the chemical and microbiological analysis of alcoholic beverages.
Several factors in the vineyard influence the sugar content in grapes: the grape variety, climatic conditions (heat), how the winemaker manages and cares for the vineyard, the timing of the harvest, and more.
“In Quebec, we have chosen to work with grape varieties that mature well in our climate,” Dominique points out. “Hybrid varieties like Frontenac, Seyval, or Vidal ripen faster than Cabernet Sauvignon, for instance, a *vitis vinifera* variety [less suited to our climatic conditions]. That said, with climate change, we can now grow Merlot or Riesling in Quebec and achieve better ripeness with these grapes.”
The sugar content of a grape is determined by its Brix level, measured using a device called a refractometer.
“Ideally, we look for a Brix level between 22 and 24,” explains Julia Torchut, oenologist at Elnova.
Once the grapes are harvested, the winemaker can introduce sugar into the wine in two ways: either by stopping fermentation or by adding sugar during fermentation, a process known as chaptalization.
“Many people are hesitant to talk about chaptalization, but it’s done all over the world,” Julia Torchut points out. “There’s no issue with it because all the sugar is converted into alcohol, leaving almost none in the final product.”
For sparkling wines, it’s a bit different. Depending on the type of sparkling wine the winemaker wants to produce, the sugar content will vary—ranging from sweet, demi-sec, sec, extra-sec, brut, extra-brut, to brut nature. Additionally, whether or not sugar is added for the second fermentation in the bottle determines whether it’s classified as a dosed or non-dosed sparkling wine.
Sugar on the Palate
What about sugar when it comes to tasting wine?
“In Quebec, we consider wines with less than four grams of sugar per liter as dry, and most wines made here fall below that threshold,” explains Julia Torchut. “To detect sugar during tasting, it typically needs to be between 6 to 10 grams per liter. Even then, I’m not sure casual tasters would notice it.”
Sometimes, a wine might give the impression of sweetness due to barrel aging or aging on lees, the oenologist adds.
That said, sugar, along with acids and alcohol content, contributes to a wine’s balance.
“A little sugar in wine isn’t a bad thing—it can sometimes enhance its roundness,” notes Dominique Fink.
Et les consommateurs aiment parfois plus le sucre qu’ils ne le pensent.
«Il y a un vigneron qui me racontait : les gens veulent un vin sec et quand je leur sers un vin à quatre grammes de sucre par litre au lieu de deux, ils l’aiment plus. On a des conceptions qui sont parfois fausses sur le vin, rappelle la biologiste moléculaire. Il y a des vins qui sont extrêmement populaires comme le Ménage à trois qui contient 12 grammes de sucre par litre. Tout dépend du marché que le vigneron veut cibler.»
Donc finalement, le sucre dans le vin est une question de raisin, et des choix du vigneron faits au champ et/ou chai.
