As a sommelier and brewer, I can provide some insight into the use of preservatives in wine. When it comes to preservatives in wine, the most commonly used additive is sulphur dioxide (SO2). Sulphur dioxide serves several purposes in winemaking, including its role as an antioxidant and antimicrobial agent.
Sulphur dioxide is added to wine in varying amounts, depending on the winemaker's preference and the wine style. White wines tend to have higher levels of sulphur dioxide added compared to red wines. This is mainly because white wines are more susceptible to oxidation due to their lower tannin content.
Oxidation occurs when wine is exposed to oxygen, leading to undesirable changes in flavor and aroma. White wines, which are typically lighter and more delicate, are particularly vulnerable to oxidation. By adding sulphur dioxide, winemakers can help prevent or slow down the oxidation process, ensuring that the wine maintains its freshness and vibrancy.
On the other hand, red wines contain higher levels of tannins, which act as natural preservatives. Tannins are compounds found in the skins, seeds, and stems of grapes, and they provide structure, texture, and astringency to red wines. These tannins have antioxidant properties and can help protect the wine from spoilage.
Due to the presence of tannins, red wines generally require less sulphur dioxide for preservation compared to whites. However, it's worth noting that sulphur dioxide is still used in red wine production to some extent, as it plays a crucial role in preventing microbial spoilage and maintaining the wine's stability.
It's also important to mention that although sulphur dioxide is the most common preservative used in winemaking, it is not the only one. Other preservatives, such as sorbic acid and potassium sorbate, may be used in certain wines to prevent refermentation or inhibit the growth of spoilage organisms.
When it comes to personal experiences, I have had the opportunity to taste and evaluate a wide range of wines throughout my career. While sulphur dioxide is present in most wines to some degree, I have noticed that certain winemakers or wine regions tend to use it more sparingly. These wines often exhibit a more natural, expressive character and may appeal to those seeking wines with minimal additives.
The wine with the most preservatives would generally be white wine, as they are more susceptible to oxidation and require higher levels of sulphur dioxide for preservation. Red wines, thanks to their natural tannins, require less sulphur dioxide but still use it to ensure stability and prevent spoilage. It's important to note that the use of preservatives in wine varies among winemakers and regions, and there are also wines available that are made with minimal or no added preservatives for those who prefer a more natural approach.