Quick answer
- The most common causes are leftover CO2, bentonite that wasn’t mixed in well, a room that is too warm, and not waiting long enough.
- Degas fully, add the fining agent, and leave the wine somewhere cool to clear.
- Never filter or bottle cloudy wine. If it is not clear, it is not ready.
A crystal-clear wine looks great and keeps better. Here is why some batches stay hazy and how to fix them.
Common Causes of Cloudy Wine
- Not fully degassed. CO2 keeps tiny particles floating, and fining agents can’t do their job. See How to Degas Wine.
- Poorly mixed bentonite. If bentonite was dumped in and barely stirred, proteins can drop out later, even in the bottle.
- Too warm. Wine clears better somewhere cool.
- Not enough time. Some wines just take longer. The longer you leave it, the clearer it gets.
- Tap or well water. Some water can leave wine hazy.
How Fining Agents Work
Fining agents carry an electrical charge that attracts the particles causing the haze. They clump together and sink to the bottom of the carboy.
Bentonite
A clay added on day 1 to remove proteins. Mix it in thoroughly. Shop bentonite.
Isinglass
The fining agent most often included with wine kits. It is gentle and works well on white wines, because unlike gelatin it doesn’t need tannins to work. It also brightens the colour. Being gentle, it sometimes doesn’t clear a wine completely.
Gelatin
The strongest of the natural finings. It also removes excess tannins and some colour, so it suits big reds better than delicate whites.
Kieselsol and Chitosan
A popular two-part fining pair. Many kits include them in place of isinglass. Kieselsol · Chitosan.
Sparkolloid
Known for working when other finings fail. It forms a firm sediment bed. To use the powder: 1 teaspoon per 4 L (1 US gal) of wine, mixed with 1 cup of wine per teaspoon. Boil for about 3 minutes, pour it into the carboy through a funnel, refit the airlock, and leave it somewhere cool for 10 days. Some fine particles can stay suspended, so filter the wine afterward.
Step-by-Step Fix for a Cloudy Wine
- Check that fermentation is finished: S.G. 0.990 to 0.995.
- Degas thoroughly.
- Add a fining agent and mix it in well.
- Move the carboy somewhere cool and dark. Don’t disturb it.
- Wait at least a week, then check. Give it more time if needed.
- Rack off the sediment, then filter for a final polish. See How to Filter Homemade Wine.
Frequently Asked Questions
How long does it take wine to clear?
Usually 1 to 2 weeks after fining, but some wines take longer, especially in a warm room.
Can I bottle cloudy wine?
We don’t recommend it. Sediment will form in the bottles, and if the haze is from fermentation that hasn’t finished, corks can push out.
Will filtering fix cloudy wine?
Filtering polishes a wine that is already nearly clear. Very cloudy wine clogs the pads and can damage an electric filter.
Shop fining agents and additives
Need a hand with your batch? Call us toll-free at 1-877-668-6160 (Monday to Friday, 8:00 a.m. to 3:00 p.m. Eastern) or send us a message.
This guide is adapted from the ABC Crafted Series booklet Wine From Kits: What the Instructions Don’t Always Tell You. Always follow the instructions that come with your kit.