Wine clarification: the art of winemaking

Wine clarification is an essential process in winemaking, carried out before bottling. Its purpose is to remove impurities and suspended particles generated during fermentation. Clarification not only improves the wine’s appearance but also enhances its organoleptic qualities, making it smoother on the palate.

Why is Wine Clarification Important?

After fermentation, wines often contain suspended particles, such as yeasts and bacteria, which can make the wine appear cloudy. Wine clarification is carried out to ensure clarity in both bottle and glass for the consumer. Additionally, proper clarification prevents certain instabilities and improves the wine’s organoleptic qualities.

How is Wine Clarified?

There are various methods of clarification. One is spontaneous clarification, which occurs when the particles settle naturally due to gravity. However, this method is not fully effective, as smaller particles may remain suspended in the wine.

To accelerate and assist the clarification process, fining agents can be added. These may be of animal origin, such as egg white and milk albumin, marine origin such as alginates, mineral origin such as bentonite or silica, or chemical in nature.

Wine Clarification Using Egg White

Clarifying wine with egg white is a tradition dating back to the 17th century. The egg white binds impurities and imparts the desired clarity naturally and organically. In this process, one egg white per hectolitre of wine is added to clarify it and soften the tannins before bottling.

Fining Agents in Wine Clarification

Fining agents are substances added to wine to speed up clarification. They coagulate in the wine, increasing the size of suspended particles and accelerating their sedimentation. Several types of fining agents are used:

1. Animal-based fining agents: These include albumins from calf or lamb’s blood for rosé wines, milk or casein for white wines, and egg or bone gelatin for red wines. However, due to concerns such as “mad cow disease,” the use of some of these agents has decreased, with egg albumin being the most commonly used for red wines.
2. Marine-based fining agents: Alginates are an example.
3. Mineral-based fining agents: Bentonite is a common example. It is used at 30 grams per hectolitre, prepared by gradually adding it to ten times its weight in water. After 48 hours of resting, it is stirred, and an equal volume of water is added. The wine is then set in motion, and the fining agent is applied gradually while maintaining movement. After 12 days, 95% of the clear wine can be separated.
4. Chemical fining agents: Silica gel is an example of this type.

Vegan Wines and Clarification

In recent years, there has been growing interest in vegan wines. What makes a wine vegan? The answer lies in the clarification process.

As mentioned, some fining agents are of animal origin, meaning wines clarified with them are not suitable for vegans. Vegan alternatives, however, are available.

Vegan wines are clarified using plant-based or mineral agents. For example, bentonite, a type of clay, is a popular vegan fining agent. Other vegan fining agents include alginate, derived from seaweed, and activated charcoal.

Additionally, some wines may clarify naturally over time without added fining agents. These unfiltered wines are also vegan-friendly but may appear cloudier and contain sediments.

Benefits of Wine Clarification

Clarification not only improves appearance but can enhance flavour and aroma. For example, egg albumin can improve the aroma and palate of red wine. Bentonite is particularly useful for white and rosé wines, as it removes proteins that could cloud the wine.

Wine Filtration

Filtration is another clarification technique, involving the removal of suspended solids by passing the wine through a filter. The aim is always to achieve clarity without compromising the wine’s taste. However, harsh filtration should be avoided, as it can remove important compounds that contribute to complexity, tannins, and colour stability.

Final Considerations on Wine Clarification

Wine clarification is a crucial winemaking step, requiring careful selection of the fining agent, proper dosage, preparation of the stock solution, application, and resting. While clarification can give wine brilliance, this clarity is typically guaranteed for up to two months. For wines intended for longer storage, filtration may also be required.

In conclusion, wine clarification is an art requiring knowledge, experience, and patience. The result is a high-quality wine with a clean, bright appearance and enhanced flavour and aroma. At Bodegas Romale, we take pride in offering wines that have been carefully clarified to provide the best possible experience for our consumers.