A new ozone based method will replace sulfite-based method of preservation

Feb 12, 2007 09:41 GMT  ·  By

It is said that the quality of a wine is in the soil, climate and ... yeast.

But mass-marketed grapes can stay stored for months and producers usually use sulfur dioxide to prevent their decay. The sulfur dioxide is effective but it is corrosive and can provoke severe allergic reactions in some people.

During the wine-making process, producers can also add sulfites to prolong their shelf-life, but these products can trigger asthma and other conditions in some people, not mentioning that they give wine a chemical flavor rejected by any real wine consumer.

Now, a team at the Technical University of Cartagena in Spain led by Francisco Artes-Hernandez has probed a new technique that employs ozone to preserve grapes. This method would prevent allergies and increase the wine's healthy compounds at the same time.

The new technique implies exposing macroperforated packages of grapes at 0 degrees C to cycles of 0.1 micro liters per liter of ozone. Comparing this method with others, the researchers found that the ozone technique had the 90% of the effectiveness of SO2 in preventing decay. Moreover, the ozone method increased four times the amounts of antioxidants compared to untreated grapes.

The precise cause of antioxidant levels increase is not known, but as these compounds emerge as a response to environmental stress in plant cells, probably their level increases to protect the cell against ozone. "Because wine growers don't store grapes for prolonged periods, they are unlikely to use ozone in any preservation process", said Andrew Waterhouse, Chair of the Department of Viticulture at University of California, Davis.

But specialists admit that the ozone technique could replace the tricky sulfites added to wine during the liquefaction process, resulting in healthier wines.

Antioxidants are natural chemicals found in red wine, chocolate, coffee and many fruits, and are supposed to be beneficial, by impeding the emergence of many conditions, like cancer and neurodegeneration.