How does oxygen impact wine?

Oxygen (its use and restriction of) is vital in wine production, wine service and wine storage. Today we're going to go over the impacts of oxygen, what's too much, what's not enough and how you can stop it from spoiling your wine as a winemaker, wine lover or sommelier.

How oxygen impacts winemaking?

Winemaking is an ancient art that combines science, tradition, and the alchemy of nature to produce the nectar of the gods. Among the many elements that contribute to the intricate dance of flavours and aromas in wine, oxygen plays a crucial role. While oxygen is often associated with decay and spoilage, in the realm of winemaking, it is a key player in shaping the character and quality of the final product.

The Oxygen Paradox:

Oxygen, despite being essential for life, can be a double-edged sword in winemaking. When exposed to excessive oxygen, wine can undergo oxidation, a process that leads to undesirable changes in colour, aroma, and flavour. However, controlled exposure to oxygen at various stages of winemaking is a deliberate and essential practice that winemakers employ to enhance the complexity and aging potential of their wines.

Oxygen's Influence During Fermentation:

The winemaking process begins with the fermentation of grape juice into wine, a magical transformation orchestrated by yeast. Oxygen's role during this stage is subtle yet impactful. Oxygen helps yeast cells reproduce and maintain a healthy fermentation environment. However, winemakers must carefully manage oxygen levels, as excessive exposure at this stage can lead to unwanted oxidation and the development of off-flavours.

Maturation in Barrels:

Once fermentation is complete, many wines embark on a journey of maturation, often in oak barrels. This phase is where oxygen truly flexes its muscles, contributing to the evolution of wine's character. Barrels are not airtight, allowing a controlled ingress of oxygen. This slow and measured exposure encourages the integration of flavours, softening of tannins, and development of desirable aromas such as vanilla and spice.


Recognising the importance of oxygen in the aging process, modern winemakers have developed techniques like micro-oxygenation. This method involves the controlled addition of tiny amounts of oxygen to wine, replicating the natural aging process but with precision. Winemakers can fine-tune the level of oxygen exposure, ensuring that it enhances the wine's structure without jeopardising its integrity.

Aging Potential and Oxygen:

Oxygen's influence becomes even more evident in wines intended for extended aging. Fine wines, especially reds like Cabernet Sauvignon and Bordeaux blends, often benefit from aging in the bottle. During this period, minute amounts of oxygen interact with compounds in the wine, leading to the development of tertiary aromas and flavours, such as leather, tobacco, and earthiness.

The Bottling Dilemma:

While oxygen can contribute to the complexity of a wine, it becomes an enemy once the wine is bottled. Exposure to oxygen in the bottle can lead to premature aging, loss of freshness, and a decline in overall quality. Winemakers employ various techniques, such as inert gas flushing and the use of high-quality closures, to minimise oxygen ingress and preserve the wine's vitality.

How oxygen impacts wine storage?

Wine, often referred to as "bottled poetry," undergoes a fascinating journey from the vineyard to the cellar. While winemakers meticulously craft their creations, the journey doesn't end with the sealing of the bottle. The storage conditions, particularly the role of oxygen, play a pivotal role in determining how a wine evolves over time. In this exploration, we'll delve into the intricate relationship between oxygen and wine storage, unraveling the mysteries that influence the aging process.

The Oxygen Conundrum:

Oxygen is a crucial element in the development of wine, fostering complex aromas and flavours during the winemaking process. However, when it comes to wine storage, the presence of oxygen can be both a blessing and a curse. The challenge lies in finding the delicate balance that enhances a wine's evolution without accelerating its demise.

Oxygen's Initial Impact:

Once a wine is bottled, the presence of oxygen initiates a series of chemical reactions that shape its character. In the initial stages, oxygen helps integrate tannins and soften the wine's structure. This controlled exposure contributes to the wine's maturation, unlocking new layers of complexity and nuance.

Corks and Oxygen Exchange:

The choice of closure plays a pivotal role in managing oxygen exposure during storage and wine maturation. Natural cork closures, despite their traditional appeal, allow for a slow exchange of oxygen between the environment and the wine. This gradual introduction of oxygen can be beneficial for certain wines, particularly those intended for extended aging. However, it also poses a risk of oxidation if storage conditions are not optimal, this is why a wine storage cabinet or freestanding wine fridge are often sought for those without country homes and cellars.

Alternative Closures and Oxygen Control:

As the wine industry evolves, alternative closures such as synthetic corks and screw caps have gained popularity. These closures offer a tighter seal, minimising oxygen exchange and reducing the risk of premature aging. While this can be advantageous for preserving the freshness of certain styles of wine, it may limit the development of complex tertiary characteristics in others.

Cellaring Conditions and Oxygen Management:

Proper storage conditions are paramount to the longevity of wine, and oxygen management is a critical aspect. Wines should be stored in a cool, dark, and humidity-controlled environment to minimise the impact of oxygen on their delicate composition. Wine cellars, whether traditional or modern, provide the ideal setting for wines to mature gracefully.

Decanting and Oxygen Exposure:

The act of decanting wine serves a dual purpose: to separate sediment and to expose the wine to oxygen. While some wines benefit from aeration and the resulting release of aromas, others, particularly older and more delicate vintages, require gentler handling to avoid excessive oxidation. Understanding the specific needs of each wine is key to making the most of the decanting process.

The Aging Dance:

As wines age, their relationship with oxygen becomes more nuanced. While some wines thrive on extended bottle aging, developing complex tertiary characteristics, others are best enjoyed in their youth, showcasing vibrant fruit flavours. The art of wine storage lies in recognising the potential of each bottle and providing the ideal conditions for its unique journey.

In the tapestry of wine storage, oxygen is a silent but powerful conductor, orchestrating the symphony of aging. Whether unlocking the hidden potential of a Bordeaux blend or preserving the freshness of a crisp Sauvignon Blanc, the impact of oxygen is undeniable. As wine enthusiasts embark on the exploration of their cellars, they become stewards of time, carefully managing the delicate dance between oxygen and wine to savour the true essence of each bottle.

How can a wine fridge stop wine oxidising too quickly?

Temperature Stability:

One of the primary functions of a wine fridge is to maintain a consistent and appropriate temperature for your wine. Unlike regular refrigerators that often have lower temperatures suited for food storage, wine fridges are set to a range ideal for wine preservation, typically between 5 to 18 degrees Celsius. This stability prevents the expansion and contraction of the wine, reducing the likelihood of air seeping into the bottle.

Humidity Control:

Proper humidity is another crucial aspect of wine storage, and wine fridges address this by incorporating humidity control features. A relative humidity level of around 70% is considered optimal for wine cellaring. This prevents corks from drying out, maintaining their integrity and ensuring a tight seal that guards against oxygen infiltration. Brands that allow personalised control over humidity include some units from Swisscave, EuroCave and mQuvee.

Protection from Light:

Exposure to ultraviolet (UV) light can be detrimental to wine, leading to the degradation of organic compounds and the acceleration of oxidation. Wine fridges are designed with UV-resistant glass or solid doors to shield your bottles from harmful light, preserving the wine's colour and flavour characteristics.

Reducing Vibration:

Wine is a delicate elixir, and excessive vibration can disturb its natural aging process. Wine fridges are engineered with anti-vibration systems or utilise absorption cooling technology to minimise disturbances. This ensures that sediments settle naturally, rather than being agitated and affecting the wine's overall stability.

Dual or Multi-Zone Functionality:

Not all wines age at the same rate or under the same conditions. Recognising this, many brands offer dual zone wine fridges.

To conclude, oxygen, with wines and humans is both a blessing and a curse, its essential, but will eventually lead to a slow decline, in order to preserve the wine for as long as possible, investing in a wine storage solution is the best way to enjoy your wine for longer.

Author - Sarah Newton

Sarah Newton has worked in the wine industry for two decades holding senior positions at some of the UK wine industry's leading brands. The MD of Coolersomm, Sarah is WSET certified and our lead wine buyer too.