The bacteria are able to convert the whole malic acid of white wines in lactic acid in less than 30 days, when this organic acid content is between 0.5 and 5 g/L.After the alcoholic fermentation carried out by the yeast in wine, it can take place the malolactic fermentation, where lactic acid bacteria metabolize the malic acid in lactic acid. This can occur naturally or by the inoculation of a specific bacterium which it leads to desirable transformations in wine. The process is common in red wines, but unusual in white wines.
The strains, isolated by scientists at the CSIC (Spain) and the Consiglio per la Ricerca e la Sperimentazione in Agricoltura (Italy), have been isolated from a fermented white wine called Caiño Blanco and produced in the North of Spain.
The bacteria are able to convert the whole malic acid of white wines in lactic acid in less than 30 days, when this organic acid content is between 0.5 and 5 g/L.
This transformation leads to a decrease (about 10%) in the sensory acidity of the white wines tested and an increase (about 15%) in the honey aroma. Moreover, in the Albariño white wine, this malolactic conversion produces an increase in its yellow-golden highlights, an increase in the herbal aroma, a decrease in the pineapple aroma, an enhancement in the body and an increase of the softness. On the other hand, in the Caiño Blanco white wine, this fermentation causes a decrease in the herbal aroma and a decrease in the bitterness.
The patent has been licensed in Spain by the company Bodegas Terras Gauda, in Galicia. Industrials partners are sought for other countries.
Contact:
Alfonso Carrascosa (
Instituto de Investigación en
Ciencias de la Alimentación
(CIAL, UAM-CSIC)