Microoxygenation
Encyclopedia
Micro-oxygenation is a process used in winemaking
Winemaking
Winemaking, or vinification, is the production of wine, starting with selection of the grapes or other produce and ending with bottling the finished wine. Although most wine is made from grapes, it may also be made from other fruit or non-toxic plant material...

 to introduce oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...

 into wine
Wine
Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...

 in a controlled manner. Developed in 1991 by Patrick DuCournau, working with the exceptionally tannic grape Tannat
Tannat
Tannat is a red wine grape, historically grown in South West France in the Madiran AOC and is now one of the most prominent grapes in Uruguay, where it is considered the "national grape". It is also grown in Argentina, Australia, Brazil, Peru, and in Italy's Puglia region where it is used as a...

 in Madiran, the process gained usage in modern winemaking following the 1996 authorization by the European Commission
European Commission
The European Commission is the executive body of the European Union. The body is responsible for proposing legislation, implementing decisions, upholding the Union's treaties and the general day-to-day running of the Union....

. Today the technique is widely employed in Bordeaux
Bordeaux wine
A Bordeaux wine is any wine produced in the Bordeaux region of France. Average vintages produce over 700 million bottles of Bordeaux wine, ranging from large quantities of everyday table wine, to some of the most expensive and prestigious wines in the world...

 as well as at least 11 different countries, including the United States
American wine
American wine has been produced for over 300 years. Today, wine production is undertaken in all fifty states, with California producing 89 percent of all US wine...

 and Chile
Chilean wine
Chilean wine is wine made in the South American country of Chile. The region has a long viticultural history for a New World wine region dating to the 16th century when the Spanish conquistadors brought Vitis vinifera vines with them as they colonized the region. In the mid-19th century, French...

.

Process

The process of micro-oxygenation 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
Volume
Volume is the quantity of three-dimensional space enclosed by some closed boundary, for example, the space that a substance or shape occupies or contains....

 of the wine. In the second chamber the oxygen is injected into the wine through a porous ceramic
Ceramic
A ceramic is an inorganic, nonmetallic solid prepared by the action of heat and subsequent cooling. Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous...

 stone located at the bottom of the chamber. The dosage is controlled and can range anywhere from .75 to 3 cubic centimetre per liter
Litér
- External links :*...

 of wine. The process normally occurs in multiple treatments that can last anywhere from one or two treatments during the early stages of fermentation
Fermentation (wine)
The process of fermentation in wine turns grape juice into an alcoholic beverage. During fermentation, yeast interact with sugars in the juice to create ethanol, commonly known as ethyl alcohol, and carbon dioxide...

 (to help avoid stuck fermentation
Stuck fermentation
A stuck fermentation occurs in brewing beer or winemaking when the yeast become dormant before the fermentation has completed. Unlike an "arrested fermentation" where the winemaker intentionally stops fermentation , a stuck fermentation is an unintentional and unwanted occurrence that can lead to...

) to a more prolonged treatment during the maturation period that can last four to eight months.

Benefits

The exposure of wine to oxygen in limited quantities can be beneficial to the wine. There needs to be a balance where too much oxygen can lead to oxidation and too little can lead to reduction
Redox
Redox reactions describe all chemical reactions in which atoms have their oxidation state changed....

 and the ensuing wine faults. In oak barrel aging, the natural properties of the wood allows for a gentle aeration
Aeration
Aeration is the process by which air is circulated through, mixed with or dissolved in a liquid or substance.-Aeration of liquids:-Methods:Aeration of liquids is achieved by:...

 of the wine to occur over a prolonged period. This aids in the polymerization
Polymerization
In polymer chemistry, polymerization is a process of reacting monomer molecules together in a chemical reaction to form three-dimensional networks or polymer chains...

 of tannin into larger molecules, which are perceived on the palate
Palate
The palate is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but, in most other tetrapods, the oral and nasal cavities are not truly separate. The palate is divided into two parts, the anterior...

 as softer. The process of micro-oxygenation aims to mimic the effects of slow barrel maturation within a shorter period and for less of the long-term cost associated with oak barrels. It also enables more control over this process, as opposed to barely observing it in such natural material containers as barrels.

During fermentation, the added oxygen can help maintain the viability
Viability
Viable or viability is the ability of a thing to maintain itself or recover its potentialities.Viable or viability may also refer to:...

 of the yeast
Yeast
Yeasts are eukaryotic micro-organisms classified in the kingdom Fungi, with 1,500 species currently described estimated to be only 1% of all fungal species. Most reproduce asexually by mitosis, and many do so by an asymmetric division process called budding...

 to minimize the risk of stuck fermentation
Stuck fermentation
A stuck fermentation occurs in brewing beer or winemaking when the yeast become dormant before the fermentation has completed. Unlike an "arrested fermentation" where the winemaker intentionally stops fermentation , a stuck fermentation is an unintentional and unwanted occurrence that can lead to...

 and the production of undesirable sulfides. After fermentation it can aid in the clarification and stabilization of the wine without resorting to the use of fining agents.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK