Microoxygenation
Controlled oxygen introduction to improve wine without oxidation faults.
Micro-oxygenation is a winemaking technique that delivers oxygen to wine under carefully controlled conditions. It was developed in 1991 by Patrick DuCournau while working with the highly tannic Tannat grape in Madiran, and its modern use expanded after the European Commission authorized it in 1996. Today, the method is common in Bordeaux and in at least eleven other countries, including the United States and Chile.
The process uses a large device with two chambers connected by valves to an oxygen tank. In the first chamber, the oxygen amount is calibrated to the wine’s volume. In the second, oxygen is injected through a porous ceramic stone at the bottom. Dosage ranges from 0.75 to 3 cubic centimeters per liter of wine. Treatment can involve one or two applications early in fermentation—to help prevent stuck fermentation—or a longer treatment lasting four to eight months during maturation.
Micro-oxygenation influences color, aroma, mouthfeel, and phenolic content. Carboxypyranoanthocyanidins serve as markers of the technique.
Controlled oxygen exposure can improve wine, but too much causes oxidation and too little leads to reduction, each producing wine faults. Barrel aging naturally allows gentle aeration over time, helping tannins polymerize into larger molecules that may precipitate, reducing astringency. Micro-oxygenation mimics this slow barrel maturation in less time or at lower cost, with greater control. During fermentation, added oxygen supports yeast viability, reducing the risk of stuck fermentation and unwanted sulfides. After fermentation, it aids clarification and stabilization without fining agents.
- Developed by
- Patrick DuCournau
- Year developed
- 1991
- Initial grape
- Tannat
- Initial region
- Madiran
- Authorized by
- European Commission
- Authorization year
- 1996
- Dosage range
- 0.75 to 3 cubic centimetres per liter of wine
Lore & Background
The process was developed in 1991 by Patrick DuCournau, working with the exceptionally tannic grape Tannat in Madiran. It gained usage in modern winemaking following the 1996 authorization by the European Commission. Today, the technique is widely employed in Bordeaux, as well as in at least 11 countries, including the United States and Chile.
The process involves a large two-chamber device with valves interconnected to a tank of oxygen. In the first chamber, the oxygen is calibrated to match the volume of the wine. In the second chamber, the oxygen is injected into the wine through a porous ceramic stone located at the bottom of the chamber. The dosage is controlled and can range from 0.75 to 3 cubic centimetres per liter of wine. The process normally occurs in multiple treatments that can last from one or two treatments during early fermentation to a more prolonged treatment during maturation lasting four to eight months.
Micro-oxygenation affects colour, aromatic bouquet, mouth-feel, and phenolic content. Carboxypyranoanthocyanidins can be considered markers of micro-oxygenation techniques.
Reader's Guide
Micro-oxygenation addresses the challenge of balancing oxygen exposure in winemaking: too much oxygen can lead to oxidation, while too little can lead to reduction, each causing associated wine faults. In barrel aging, the natural properties of wood allow gentle aeration over a prolonged period, aiding polymerization of tannins into larger molecules that may fall out of solution, thereby improving mouth astringency. Micro-oxygenation aims to replicate these effects in a shorter time or at lower cost, while enabling more precise control. During fermentation, the added oxygen helps maintain yeast viability, minimizing the risk of stuck fermentation and the production of undesirable sulfides. After fermentation, it can aid in clarification and stabilization of the wine without resorting to fining agents. The technique has become widely adopted in Bordeaux and in at least 11 countries, reflecting its significance as a modern tool for managing oxygen exposure and improving wine quality.
Did You Know?
- Micro-oxygenation was developed in 1991 by Patrick DuCournau working with Tannat grapes in Madiran.
- The European Commission authorized the technique in 1996.
- Dosage ranges from 0.75 to 3 cubic centimetres of oxygen per liter of wine.
- Carboxypyranoanthocyanidins can be markers of micro-oxygenation techniques.
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