noun / verb From Old French fin (fine, pure); the process of making wine fine — clear and stable — has been practised since ancient Rome

Fining /ˈfaɪnɪŋ/

A winemaking process in which a substance (the fining agent) is added to wine to attract, bind with and precipitate unwanted particles — proteins, tannins, colour compounds or off-flavours — so that they can be removed by settling and racking or filtration. The fining agent is not intended to remain in the wine; it is removed along with the particles it has bound.

Common fining agents

Bentonite

A type of clay (montmorillonite) with a negative charge, used primarily in white and rosé wines to remove unstable proteins that would otherwise cause heat-induced haziness. The most common fining agent for white wines. Bentonite is also used in some vegan wines as it is mineral-based.

Egg whites (albumen)

Positively charged proteins in egg white bind with large, harsh tannins in red wine, softening the texture. The most traditional agent for high-quality red wines — still used in Bordeaux and Burgundy. 2–6 egg whites per 225-litre barrique. Renders wines non-vegan.

Isinglass

A fining agent derived from dried fish swim bladders, used mainly in white wines and Champagne to remove yeast cells and produce brilliance. Very effective in small doses. Renders wines non-vegan.

Casein (milk protein)

Used to remove oxidative browning and certain off-flavours. Can also reduce over-oaked bitterness. Traces may remain in wine — relevant for milk-allergic consumers. Renders wines non-vegan.

Activated charcoal / PVPP

Used to remove excessive colour, browning or certain aromatic off-compounds. PVPP (polyvinylpolypyrrolidone) is synthetic and effective for removing oxidised phenolics. Both are vegan. Used in white and rosé wines to improve appearance and freshness.

Why fining matters

Freshly fermented wine contains many compounds in suspension: dead yeast cells, grape protein fragments, polyphenolic particles and colour compounds. Left unchecked, these can cause haze, instability or off-flavours in the bottled wine. Protein haze in white wine — caused by proteins reacting with heat during storage or transit — is one of the most common causes of wine returns. Bentonite fining removes these proteins before bottling, producing a wine that remains clear even when exposed to warmth. Tannin management through egg white fining is a traditional tool that remains in use because it works: the texture of an egg-white-fined Bordeaux is measurably different — softer, more integrated — than the same wine unfined.

The natural wine approach

Many natural wine producers choose not to fine their wines as part of a broader commitment to minimal intervention. The philosophy is that fining removes not only unwanted particles but potentially desirable complexity and character. Unfined natural wines are often hazy, particularly those with extended skin contact (see the orange wine guide). Haze in a wine explicitly produced without fining is not a defect — it is a deliberate stylistic statement. The debate between conventional winemakers (who argue fining produces stability and consistency) and natural winemakers (who argue it strips character) is genuine and ongoing. The tannin in unfined red wines may also be more pronounced — which some drinkers prefer.

Sources: OIV (oenological practices, fining agents), WSET (winemaking curriculum, Level 3), AWRI (protein stability and fining research), Jancis Robinson MW — Oxford Companion to Wine (fining entry). Corrections via the contact form.

Questions

About fining.

What is fining in winemaking?

Fining is the process of adding a substance to wine to clarify it and improve stability. The fining agent — typically a protein, mineral or other compound — binds electrostatically with unwanted particles in the wine: unstable proteins (which would otherwise cause haze in white wines), harsh tannins (in red wines), colour compounds or off-flavours. The agent and the particles it has bound then precipitate and can be removed by racking (siphoning the clear wine off the sediment) or filtration. The goal is a cleaner, more stable wine. Fining is distinct from filtration: filtration passes wine through a physical barrier; fining uses chemistry to aggregate particles first.

Is fined wine vegan?

Not necessarily. Several common fining agents are animal-derived: egg white (albumen) is used to soften red wine tannins; isinglass (from fish swim bladders) is used to clarify whites and Champagne; casein (from milk protein) is used to reduce browning. While these agents are removed from the finished wine, trace amounts may remain, and the production process uses animal products — which is why many vegans avoid wines fined with these agents. Vegan-friendly fining agents include bentonite (clay), PVPP and activated charcoal. Many producers now label their wines as vegan or indicate on sites like Barnivore which fining agents were used.

What is unfined wine?

An unfined wine is one that has not had any fining agent added. The wine's clarity is achieved through settling, racking and sometimes filtration alone, or the wine is bottled with its natural turbidity intact. Many natural wine producers deliberately avoid fining as part of a minimal-intervention philosophy — the wine may be hazy or cloudy in the glass. This is not a defect in unfined wines; it reflects the presence of natural yeast cells, proteins and other particles. See the orange wine guide for how natural wines are typically made without fining or filtration.

Does fining affect the taste of wine?

Yes — intentionally, in some cases. Egg white fining of red wine reduces harsh or aggressive tannins, producing a softer, more rounded texture. This is a deliberate stylistic tool used in Bordeaux and Burgundy to refine young wines. Bentonite fining of white wine removes proteins but does not significantly alter flavour; however, it can strip some aromatic compounds, so winemakers use it conservatively. Activated charcoal fining removes certain off-flavours but can also remove positive aromatic compounds. Unfined wines — particularly natural wines with extended skin contact — often have a different textural and flavour profile from heavily fined equivalents: more grip, more complexity, sometimes more haze. See the tannin glossary entry for how tannin management affects texture.

Do fining agents end up in the wine I drink?

The goal of fining is that the agent is removed before bottling — it precipitates along with the particles it has bound and is racked or filtered out. In practice, trace amounts of fining agents may remain in the finished wine, particularly casein (milk protein) and isinglass. The EU requires wines to carry allergen warnings if they have been fined with egg or milk products and those allergens may be present above a threshold level. For consumers with severe allergies to eggs, fish or milk, it is worth checking whether the wine is fined with animal-derived agents. For the vast majority of consumers, the trace amounts present no health concern, but the vegan question is separate from the allergy question.

Is fining the same as filtering?

No — they are distinct processes that are often used in combination. Fining uses a chemical or biological agent added to the wine to aggregate (clump together) unwanted particles, which then settle out and are removed. Filtration passes wine through a physical barrier (a pad, membrane or earth filter) that physically removes particles above a certain size. Both aim to produce a clear, stable wine. Some producers use only fining (no filtration), some use only filtration, some use both, and some use neither (unfined and unfiltered). Unfiltered wines may throw sediment in bottle; unfined wines may be hazy. Neither is a fault in a wine produced this way intentionally.