What Is Must in Winemaking?

The term 'must' describes freshly pressed grape juice at the start of the winemaking process — before fermentation transforms it into wine. Understanding must helps explain why different winemaking decisions lead to dramatically different results in the finished wine, including differences in sugar content, calorie count, and flavour.

What is must?

Must (from the Latin vinum mustum — 'young wine') is the mixture of grape juice, skins, seeds, and sometimes stems created immediately after pressing. It's thick, opaque, and high in natural sugar — typically 10–25% glucose, depending on grape variety and ripeness. The solid portion (skins, seeds, stems) is called pomace, which makes up 7–23% of the must's total weight.

How does must become wine?

Yeast naturally present on grape skins — or cultured yeasts added by the winemaker — begin consuming the sugar in must and converting it to alcohol and CO2 through fermentation. The duration and temperature of fermentation, and how long the pomace stays in contact with the juice, determine much of the finished wine's character: its colour, tannin levels, acidity, and — crucially for DrinkWell's range — its residual sugar content.

Must and residual sugar

Residual sugar is what remains in the wine when fermentation ends. In a fully dry wine, fermentation continues until essentially all fermentable sugar has been converted to alcohol — leaving 0g or near-zero residual sugar. In sweeter wines, fermentation is stopped early (a process called stuck fermentation) or sugar is added after fermentation (chaptalisation), preserving or adding sweetness.

All wines at DrinkWell are produced by allowing full fermentation — no stuck fermentation, no post-fermentation sweetening. The result is 0g of sugar per 125ml serving across our entire range, regardless of grape variety or style.

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• Zero sugar wine — 200+ bottles confirmed at 0g per serving
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