Scientists have discovered why forest fires spoil the taste of the wine

© Fotolia / Maksim ShebekoБокалы wineScientists have discovered why forest fires spoil the taste of the wine© Fotolia / Maksim Shebeko

The chemists from Germany found out why the wine often acquires an unpleasant «ashy» taste in cases, when the grapes growing near the areas of forest fires, and published their findings in an article in the Journal of Agricultural and Food Chemistry.

«Taste and smell like wine people are often called «ash» or even «ogurechny». Most importantly, such deterioration of the properties of the drink and what the vineyard grew near the centers of forest fires, it is possible to learn only after the wine ripen,» says Katja Hertel (Katja Hertl) from the technical University of Munich (Germany).

In recent years, scientists have been actively interested in what was happening inside of wine barrels during the maturation of different brands of wine and champagne, as well as inside tubes and bottles with a ready product. For example, recently the Russian chemists found out why the cherry wine from the barrels has a pleasant taste, and their foreign colleagues – revealed the secret of producing champagne from the famous «Veuve Clicquot».

Hertel and her colleagues at the University studied the reverse phenomenon is why the taste of wine is often irreversibly deteriorate if the raw materials for its production are grown near areas of forest or Prairie fires. «Ash» taste of the wine, as the researchers note, is today a big problem for winemakers in Italy and Australia, since the probability of its development they can’t predict or prevent.

Scientists have tried to find the answer to this question by comparing the chemical composition of grape berries, cultivates in normal conditions and under constant smoke areas, and following what is happening in the process of fermentation for making wine.

As it turned out, the «blame» for the development of such a taste was a very special enzyme that is contained in large amounts in the pulp of some varieties of grapes and is involved in the formation of bonds between the sugar molecules in grape juice and aromatic substances contained in the smoke.

This compound, glycosyltransferase, performs an important function in the life of the grape – it plays an important role in the transport of resveratrol, one of the most useful substances in the wine and in grape juice. Resveratrol, as scholars have noted, similar in structure to the molecules of smoke flavor, which enzyme is often «wrong» and connects them with sugars instead of resveratrol.

This process, according to Hertel, explains why the «ash» taste and smell of the wine does not manifest itself until the drink is ready – the molecules of smoke remain attached to sugars as long as they do not break down the enzymes of yeast.

This fact, as the researchers note, can be used in order to create new varieties of grapes or yeast, which would be deprived or glikoziltransferaz, or would not split these molecules. In addition, the chemists suggest that you can create a special artificial sugar, which combines with the aromatic molecules of the smoke and thus would be inedible to the fungus. All this would help to improve the taste of the wine and protect the wine those parts of the world, where frequent fires, from unpleasant surprises.