The Everything Guide to Brettanomyces in Wine

Sep

The Everything Guide to Brettanomyces in Wine

The Everything Guide To Brettanomyces In Wine

In the world of winemaking, there's a tiny yet notorious character that can dramatically influence the taste, aroma, and overall quality of your wine. We're talking about Brettanomyces, or simply "Brett," as it's affectionately known in the wine industry. For winemakers, enthusiasts, and everyone in between, understanding Brettanomyces is crucial.

In this comprehensive guide, we'll delve deep into the world of Brettanomyces in wine, from its origins and effects to detection, prevention, and elimination strategies. Whether you're a winemaker, distributor, collector, or simply a wine lover, read on to uncover the mysteries of Brettanomyces and how it can impact your cherished vintages.

Brettanomyces in wine

Brettanomyces under a microscope

What is Brett?

To the uninitiated, "Brett" might sound like a nickname for a friend, but in the world of winemaking, it refers to something far less friendly. Brett, short for Brettanomyces, is a microscopic yeast that holds the power to make or break a wine, and its influence can be both intriguing and devastating.

Brettanomyces bruxellensis, to give it its full scientific name, is a wild yeast strain that has been causing quite a stir in the wine industry for centuries. Its presence in wine can be both intentional and unintentional, and its effects are polarizing, leading to intense debates among winemakers, sommeliers, and wine enthusiasts alike.

The Origins of Brettanomyces

The name "Brettanomyces" is derived from Greek, with "brettan" meaning "British" and "myces" meaning "fungus" or "yeast." This yeast strain was first isolated in the late 19th century in English beer, but its presence in wine was discovered later. While it has been described as a "wine fault," its influence can sometimes be considered desirable in certain styles of wine.

A Pervasive Intruder

Brettanomyces, once introduced into a winery, can be a persistent intruder. It has an uncanny ability to survive in the winemaking environment, even when rigorous sanitation measures are in place. Its resilience makes it a formidable foe for winemakers, as it can linger in barrels, tanks, and equipment, waiting for the right conditions to wreak havoc.

Brettanomyces in Wine

The influence of Brettanomyces on wine is primarily through the production of volatile phenols. These compounds can impart a range of aromas and flavours, including barnyard, leather, smokiness, and medicinal notes. In small quantities, some tasters find these nuances intriguing and complex, contributing to the wine's character. However, in excess, they can overwhelm the wine, leading to off-putting and unpleasant sensory experiences.

The Love-Hate Relationship

Brettanomyces has created a love-hate relationship in the wine world. Some winemakers actively embrace it, believing that a touch of Brett can add depth and complexity to certain wine styles. In contrast, others consider it a formidable adversary, capable of ruining entire vintages.

Brett in Beer and Spirits

While we primarily associate Brettanomyces with wine, it also makes appearances in the realms of beer and spirits. In the craft beer world, Brett is used intentionally in the production of sour and wild ales, where its character is celebrated. In the world of spirits, it can occasionally appear, adding unique notes to aged products like whisky.

How Does Brett Happen? The Unpredictable Nature of Brett

One of the most frustrating aspects of Brettanomyces is its unpredictability. It can strike when least expected, even in wines that have been meticulously crafted and monitored. The presence of Brettanomyces is not solely a result of negligence; it can happen to even the most seasoned winemakers. Understanding how Brettanomyces finds its way into your precious wine barrels is crucial for preventing its unwanted presence.

The Vineyard Origins

Brettanomyces doesn't simply materialise in the wine cellar. Its journey begins amidst the vines themselves. Brettanomyces bruxellensis, the most common culprit, is known to reside on grape skins. This yeast strain is resilient and can survive even the harshest conditions, waiting for the perfect moment to make its move.

During the grape harvest, the berries come into contact with these yeast cells. As they are crushed, the grape juice, now teeming with sugar, becomes an irresistible invitation for Brettanomyces to flourish.This is the first step in the wine's journey towards becoming a host to this intruder.

Barrel Aging – A Perfect Hideout

Once the grapes are crushed and the juice is extracted, the wine is transferred to barrels for ageing. This is where Brettanomyces often finds its ideal hiding spot. Wooden barrels, especially those that have been used for several vintages, may carry traces of Brett from previous encounters. These microscopic cells can lay dormant, ready to spring into action when conditions are right.

Brett's affinity for barrels lies in the wood itself. The porous nature of oak allows the yeast to infiltrate the wood's fibres, making it challenging to eliminate. Over time, the wood can become a breeding ground for Brett, which can continue to release its influence into future vintages stored in the same barrels.

The Role of Sulfur Dioxide

Sulfur dioxide (SO2) is a winemaker's best friend when it comes to preserving the quality of wine. It acts as a preservative and antimicrobial agent, preventing the growth of unwanted microbes, including Brettanomyces. However, if the winemaker is not diligent in monitoring and maintaining proper S02 levels, Brett can seize the opportunity to thrive.

In some cases, the presence of Brett can even lead to a phenomenon known as "sulfur-bound Brett, "where the yeast forms compounds with SO2, rendering it ineffective in controlling microbial growth. This creates a challenging situation for winemakers, as they must find alternative methods to combat Brettanomyces.

Unintentional Fermentations

Brettanomyces can also rear its head during the winemaking process itself. If winemakers do not take measures to control fermentation, Brett may spontaneously start its own fermentation. This can occur if the winery environment is not properly sterilised or if equipment is not adequately cleaned and sanitised.

Once Brettanomyces starts fermenting, it can be challenging to stop. It produces volatile phenols, compounds that can drastically alter the aroma and taste of the wine. This is why winemakers must be vigilant in maintaining a clean and controlled fermentation environment.

what are wine tannins

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I Have Brett. What Happens Now?

So, you've identified the presence of Brett in your wine. What should you do next? We'll walk you through the steps to take when you discover this pesky yeast in your cellar.

1. Assess the Extent of the Infestation

First and foremost, you need to assess the extent of the Brettanomyces infestation. Is it a minor presence or a full-blown invasion? This assessment will help you determine the appropriate course of action. Signs of Brettanomyces include off-putting aromas and flavours like barnyard, band-aid, or sweaty saddle. If you're unsure, consult with a wine sensory expert who can provide a professional assessment.

2. Isolate the Affected Wine

Isolation is key to preventing further contamination. Remove the affected wine from any barrels, tanks, or containers immediately. This step is crucial to ensure that Brett doesn't spread to other wines in your cellar.

3. Determine the Wine's Value and Purpose

Consider the value and purpose of the wine in question. Is it a high-end vintage with potential for ageing, or is it a more straightforward table wine? This assessment will guide your decision on whether to salvage the wine or use it for blending.

4. Consider Blending

Blending can be an effective way to mitigate the influence of Brettanomyces. By blending the affected wine with clean, Brett-free wine, you can dilute the off-putting flavours and aromas. This approach is often used for wines with lesser value or those intended for early consumption.

5. Consider Filtration

Filtration is another option for removing Brettanomyces cells from the wine. However, it's essential to note that this method may not completely eliminate the yeast and its byproducts. Still, it can be a useful tool when combined with other strategies.

6. Barrel Cleaning with Steam

Cleaning wine barrels using steam is a proven method for removing Brettanomyces (Brett) contamination and ensuring the preservation of your precious wines. Steam effectively sanitises the interior of the barrel, killing off the Brettanomyces yeast and neutralising its impact on your wine.

Always follow safety precautions, consult the user manual for your steam generator, and consider seeking advice from experienced winemakers when using this technique. Properly cleaned barrels will contribute to the production of exceptional wines free from Brettanomyces-related issues.

Brettanomyces Removal

Steam cleaning barrels since early detection

Conclusion

Brettanomyces may be a small yeast, but its impact on wine is enormous. From its origins to detection, prevention, and elimination, understanding Brett is vital for anyone involved in the world of wine. Whether you're a seasoned winemaker or a wine enthusiast, this guide equips you with the knowledge and tools to tackle Brettanomyces head-on, ensuring your wine stays pristine and delicious.