Why do we use bentonite in white wines?

Answered by Kyle Floyd

As an expert sommelier and brewer, I have come across the use of bentonite in white wines on numerous occasions. Bentonite, a type of clay, serves a specific purpose in winemaking – the removal of proteins from and . This process is crucial in ensuring the clarity and stability of the final product.

One of the key reasons for using bentonite in white wines is its unique ability to react with proteins. Bentonite is a negatively charged clay colloid, while proteins in carry a positive charge. This electrical attraction between the two allows bentonite to bind with the proteins, forming insoluble complexes that settle to the bottom of the vessel. This process, known as fining, effectively removes proteins from the wine.

Proteins can cause haziness or cloudiness in white wine, which is undesirable both aesthetically and from a sensory perspective. When proteins are present in the wine, they can form visible particles or create a hazy appearance. This can negatively impact the consumer's perception of the wine's quality. By using bentonite as a fining agent, winemakers can achieve a clear and visually appealing product.

Moreover, the presence of proteins in white wine can also lead to instability issues. These proteins can interact with other wine components, such as tannins and phenolic compounds, forming complexes that are prone to precipitation or haze formation. This can result in sedimentation or even the formation of undesirable crystals in the wine bottle over time. By removing proteins with bentonite, winemakers can enhance the stability of the wine, ensuring that it remains clear and free from any unwanted precipitates.

In my own experience as a sommelier, I have witnessed the impact of bentonite fining on the quality of white wines. Wines that have undergone bentonite fining tend to have a brighter and clearer appearance, which is visually appealing to consumers. Additionally, these wines often exhibit improved stability, both in terms of their visual appearance and taste. They are less likely to develop sediment or haze, even after extended periods of storage.

It is worth noting that while bentonite is highly effective in removing proteins, it can also remove other desirable wine components such as aroma compounds and polyphenols. Therefore, winemakers must carefully consider the dosage and timing of bentonite addition to strike a balance between protein removal and the preservation of desirable wine attributes. This requires a keen understanding of the specific characteristics and requirements of each individual wine.

Bentonite is used in white wines to remove proteins, which can cause haziness and instability. Its negatively charged nature allows it to react with positively charged proteins, precipitating them from the wine. The use of bentonite results in wines that are visually clear, stable, and free from unwanted precipitates. However, careful consideration must be given to dosage and timing to avoid removing other desirable wine components.