Racking
The process of transferring wine from one vessel to another to separate it from the sediment (gross lees) that has settled — a standard cellar operation during élevage.
In depth
After fermentation, dead yeast cells, grape fragments, tartrate crystals, and other particles settle to the bottom of the barrel or tank as "lees." Gross lees (heavy sediment from early fermentation) can cause off-flavours if left in prolonged contact with the wine. Racking removes the clear wine from above the sediment by pumping or siphoning it into a clean vessel, leaving the lees behind.
Racking serves multiple purposes: it separates wine from gross lees (quality); it introduces small amounts of oxygen (which can soften tannins and help integrate oak — or, if excessive, oxidise the wine); and it allows inspection and quality checking of each barrel.
In traditional Bordeaux élevage, red wines are racked every 3 months or so during their 18–24 months in barrel — typically 4–6 times total. Each racking is an opportunity to blend, assess quality, and adjust.
Natural wine producers often minimise racking to preserve the wine's natural character and CO₂ protection. The opposite approach — leaving wine on fine lees without racking for extended periods (sur lie) — is deliberately chosen for certain white wine styles.
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Frequently asked questions
- Why does racking introduce oxygen into wine — is that intentional?
- Yes, in controlled amounts. Each racking exposes the wine to a small amount of oxygen as it is transferred from vessel to vessel. In moderation this benefits red wine: it softens tannins through polymerisation, helps integrate oak flavours, and can reduce reductive notes. Winemakers adjust racking frequency based on the wine's needs — a tannic young red may benefit from several rackings; a delicate white is racked as gently as possible to avoid oxidation.
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