Fining
A clarification technique where a fining agent is added to wine to bind with and precipitate out unwanted particles — such as proteins, tannins, or colour pigments — leaving a clearer, more stable wine.
In depth
Wines naturally contain proteins, phenolics, colloids, and other particles that can cause haziness or instability. Fining involves adding a substance that attracts and binds these particles through charge interactions, causing them to clump together and settle out.
Common fining agents: Bentonite (clay) — removes protein; egg white (albumin) — softens tannin in reds; isinglass (fish bladder) — clarifies delicate whites; casein (milk protein) — removes oxidised phenolics; gelatin — removes excess tannin; activated charcoal — removes colour or off-flavours from white wines.
The choice of fining agent depends on the problem being solved. Egg white fining of red Bordeaux is traditional and adds a subtle softening of tannin. Bentonite for protein stability is standard for whites destined for warm climates.
Vegan and vegetarian wine considerations: Animal-derived fining agents (egg white, isinglass, casein, gelatin) are largely removed from the wine before bottling, but trace residues may remain. Many producers now use bentonite or PVPP (synthetic polymer) fining exclusively to make wines suitable for vegans. "Unfined" wines are increasingly common, particularly in the natural wine movement.
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Frequently asked questions
- Does fining a wine affect its quality?
- Fining can affect both positively and negatively. Egg white fining of red wine can soften harsh tannins and improve the wine's texture. But excessive or inappropriate fining can strip flavour compounds, reduce complexity, and affect the wine's long-term development. Many premium producers minimise fining (or fine only with egg white) and avoid filtration to preserve the wine's full character. "Unfined and unfiltered" is increasingly seen as a quality signal.
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