Concept card Process
White winemaking
In one sentence
Winemaking in which the grapes are pressed before fermentation: the juice, parted from the skins, ferments without them and lacks a red's colour and tannin.
From grapes to white wine
Straight to the cellar
Without the skins' protection, the juice oxidises fast.
Direct pressing
Whole or lightly crushed grapes, pressed with no maceration.
Settling
The solids in the juice settle out in the cold.
A cool fermentation
Usually between 14 and 20 °C.
Malolactic and lees
Malolactic carried out or blocked; lees ageing possible, sometimes stirred.
Key points
- Pressing before fermenting is what separates white from red, and most of what follows stems from it.
- Without the skins' protection, the juice is more exposed to oxidation, so it is protected at every stage.
- Pressing in stages, the pneumatic press keeps the finest juice apart from the coarser tailles.
- Malolactic is a choice: blocked to keep tension, carried out to round the wine.
What it changes in the glass
- A cool fermentation keeps the fruity and floral aromas, which partly fade at higher temperatures.
- Malolactic blocked: brighter acidity. Carried out: a rounder wine.
- Ageing on the lees adds richness and complexity.
Not to be confused with…
The juice ferments with the skins, which give it colour and tannin; pressing comes afterwards.
A blanc de noirs
Not a different process: white winemaking applied to black grapes, pressed quickly and very gently with no maceration, so the juice stays almost colourless.
Picked white grapes, somewhat damaged, wait half a day before going to the press. What does their juice mainly risk?
One question to test yourself: it does not count towards your progress.
Protecting a fragile juice
Reds get tannic and antioxidant protection from the skins; white juice lacks it and browns quickly in air. The whole point is to protect it from grape to press, press to tank, and tank to bottle.
- Grapes are often picked early in the morning, to keep freshness and acidity.
- They reach the cellar quickly, sometimes under inert gas or with a light, early dose of sulphur.
From press to tank
12 to 24 h
of settling in the cold: the time it takes the solids in the juice to sink
- The pneumatic press works gently, in stages of rising pressure: free-run juice first, the more tannic tailles at the end of the cycle.
- The solids are fragments of pulp, skin and earth. They are left to settle, or removed by centrifuging or flotation.
- Too cloudy, the juice ferments with herbaceous, reductive smells; too clear, it starves the yeasts of nutrients and the wine of substance.
A cool fermentation
The clarified juice usually ferments in temperature-controlled stainless steel, far cooler than a red. Above about 20 °C, the fruity and floral primary aromas, the most volatile ones, partly fade before fermentation ends.
Barrel fermentation, rarer and warmer, serves styles that seek richness and oak that blends in early.
Malolactic, a choice of style
- Blocked with cold or sulphur, it leaves the malic acidity and the wine's tension in place.
- Carried through, it softens the acidity and rounds the wine out.
- Both coexist within one region, white Burgundy for instance, depending on the winemaker.
- Neither clearly blocked nor completed, it can leave an unstable wine that may referment in bottle.
Lees and stirring
The fine lees are dead yeasts lying at the bottom of the tank or barrel. As they break down, they release compounds that add richness, complexity and some protection against oxidation.
- Bâtonnage stirs the lees back up with a rod and strengthens the effect.
- Overdone, it risks reductive notes (egg, cabbage, struck match), then corrected by controlled aeration.
To learn it in depth
Related reading
Sources (4)
- Reference bookHandbook of Enology, Volume 1: The Microbiology of Wine and Vinifications— Wiley
- Reference bookThe Oxford Companion to Wine— Oxford University Press
- Reference bookUnderstanding Wine Chemistry— Wiley
- Reference bookWSET Level 3 Systematic Approach to Tasting Wine (SAT)— Wine & Spirit Education Trust