Sugars in Wine Explained

Today, we’re focusing on an essential topic that influences how we experience wine, and that is, sugars.

Regardless of the type of wine or style of wine you prefer, sugar, and its profile on a wine, plays a considerable role in the enjoyment you experience on the palate, and as such, it is a topic worth exploring. Let's begin.

Where Do the Sugars in Wine Come From?

The sugars in wine originate naturally from grapes. As grapes ripen on the vine, they produce sugars, mainly glucose and fructose, through photosynthesis. These sugars accumulate in the fruit, providing the energy yeast needs during fermentation.

When winemakers add yeast to grape juice, the yeast consumes most of these sugars, converting them into alcohol and carbon dioxide. However, not all sugars are fermented. The sugar that remains after fermentation is called residual sugar (RS), and it’s what gives wine its sweetness.

Finally, the balance between residual sugar, alcohol, and acidity shapes the wine’s taste and mouthfeel.

How Do Different Wines Get Their Sweetness Levels?

The sweetness of a wine depends largely on how much sugar is left after fermentation:

• Dry wines have little to no residual sugar because fermentation is allowed to complete fully.

• Off-dry or medium dry wines contain a small amount of residual sugar, giving a subtle hint of sweetness.

• Semi-sweet wines have a noticeable sweetness but still maintain balance.

• Sweet wines often come from late-harvest grapes or are made by stopping fermentation early, leaving a high level of residual sugar.

Climate and grape variety also influence sugar content. Grapes grown in warmer climates tend to have higher sugar levels, while cooler climates produce grapes with less sugar and higher acidity.

The Wine Sweetness Scale

Here’s a simple guide to understanding wine sweetness based on residual sugar content:

Classification	Residual Sugar (g/L)	Taste Profile
Dry	0–9	Crisp, no perceptible sweetness
Off-Dry / Medium Dry	10–17	Slight sweetness, balanced
Semi-Sweet / Medium Sweet	18–45	Noticeably sweet
Sweet	45+	Rich, dessert-like sweetness

Most everyday table wines fall into the dry category, while dessert wines and some fortified wines are sweet.