Clearing, Filtering & Bottling Wine: The Last Step to a Finished Wine

Clarifying and bottling wine

Why clarify?

A cloudy wine isn't bad – but a clear one looks better and keeps longer. Cloudiness comes from yeast residue, proteins, pectins and tartrate crystals.

Natural clarification

The simplest way: time and cold. Store the wine at 0–5 °C (cellar, refrigerator). Cloudy particles settle within 4–8 weeks. Then rack.

Fining agents

Bentonite – a clay mineral that binds proteins. 1–3 g/liter, let swell in water, stir in, wait 1 week, rack.

Gelatine + kieselsol – for tannic red wines. Gelatine binds to tannins and precipitates.

Pectic enzyme – an enzyme that breaks down pectin haze (especially in apple, quince wines).

Activated charcoal – only for strong browning or off-flavors, use sparingly.

Filtering

For crystal-clear wine: a pleated filter or wine filter machine (from approx. €50). Filter paper No. 1 (coarse) to No. 3 (fine).

Alternative: pour the wine through a fine sieve or cheesecloth.

Sulfiting before bottling

Potassium metabisulfite (Campden): According to the LVWO Weinsberg, the wine should contain 30–40 mg/l of free sulphurous acid at bottling. Measure the level and add only what is missing – 100 mg of potassium metabisulfite yields about 50 mg of SO₂. The legal maximum for total SO₂ is, for example, 150 mg/l for dry red wine and 200 mg/l for dry white wine. Protects against oxidation and germs in the bottle.

Bottles & corks

• Wine bottles 0.75 liters made of glass (returnable bottles from the supermarket are ideal)
• Rinse bottles with a Campden solution
• Natural cork: needs a corkscrew, good for aging > 1 year
• Screw cap: practical, ideal for young wines that will be drunk quickly
• Crown cap (with a capping tool): inexpensive; for sparkling wine only together with pressure-resistant sparkling-wine bottles

Labeling & storage

• Cool (10–15 °C), dark, bottles lying down (to keep the cork moist)
• Red wine: let mature for at least 6–12 months
• Fruit wines: often best after 3–6 months

Tip: Fill a small tasting bottle – that way you can follow the aging process without opening a full bottle.

Sources

• State Teaching and Research Institute for Viticulture and Pomology Weinsberg (LVWO): Weinqualität sichern durch richtige Schwefelung, accessed 5 Oct 2026

The sources support individual statements in this article. The organisations named have neither reviewed nor endorsed it.