Description

Sodium Bentonite

Winemakers can use sodium bentonite as a fining agent in wines and ciders. Simply mix with hot water before adding to juice or wine, following the instructions on the label.

What is sodium bentonite?

Bentonite is a naturally occurring clay that forms over millions of years from the weathering of volcanic ash. People widely consider it the “clay of a thousand uses” because it can absorb water and bind with other substances. Scientifically, montmorillonite forms the main component of the clay, giving it its signature swelling and sticky properties.

Why winemakers use sodium bentonite

• Clears cloudy wine – Bentonite removes proteins and haze-forming particles that make wine look cloudy.
• Improves stability – It prevents protein haze from forming later in the bottle.
• Speeds up clarification – Wine clears faster than it would naturally.
• Works well with fruit wines – Many fruit wines contain more proteins, so bentonite helps them clear properly.
• Improves appearance – Clear wine looks more professional and appealing.

When to add bentonite

Winemakers typically add bentonite:

• At the start of fermentation (common in fruit winemaking), or
• After fermentation if the wine remains cloudy.

Many home winemakers add it early because fermentation helps mix the bentonite thoroughly, making it more effective.

How does Bentonite work as a fining?

Bentonite naturally carries a negative electrical charge. Many of the haze-forming proteins in wine carry a positive charge – especially in white wines. When you add the bentonite, the negative charge on the clay attracts and binds to the positively charged proteins. This bentonite-protein complex clump together into larger particles, they become heavier and start to settle at the bottom of the fermenter. As the particles settle, the wine above becomes clear, free of haze or cloudiness. This also reduces the risk of a protein haze forming later in the bottle. Bentonite can also bind trace metals and other colloidal particles, improving stability and shelf life.

Why Choose Sodium Bentonite?

Unlike calcium-based alternatives, sodium bentonite offers a superior swelling capacity and a high negative surface charge. This makes it an incredibly efficient “magnet” for positively charged proteins that cause unwanted cloudiness or “protein haze” after bottling.

How to Achieve the Best Results

To maximize the efficacy of sodium bentonite, it must be properly hydrated before addition. Mixing the powder into hot water (approx. 60°C) creates a smooth slurry that increases the available surface area, ensuring every gram works to its full potential.