Vegetable tannins against the lightstrike

22 July 2023

The bottle is on the table, at the right temperature. Uncork casually, but at the moment of tasting something goes wrong: the wine in the glass gives off an unpleasant scent, reminiscent of cooked cauliflower, garlic, or even wild game.

You have run into the lightstrike, a problem that mainly affects white and rosé wines, both still and sparkling. This is an increasingly widespread phenomenon, thanks to the choice of many producers to use transparent glass for their wines.

At the Faculty of Agriculture of the University of Milan, this problem has been studied for 3 years with a dedicated project, Enofotoshied, and at the end of May, the results of the research were presented at a conference.

Among the speakers was Alessandro Schiavi, the winemaker from Mirabella, one of the companies participating in the project. “The aromatic deviation due to exposure to light causes the wine to produce sulfur molecules, responsible for the aromas of cooked, boiled meat and animals”, says Schiavi.

“In Mirabella, we use dark glass, perhaps less glamorous but certainly safer, especially when the bottles arrive from the customer and remain on the shelves for a long time, exposed to increasingly aggressive light sources. But no wine producer can be said to be totally free from the risk of a lightstrike, even brief exposure to lighting in the cellar interferes, albeit minimally, with the wines and can slightly modify them”.

“For three years we have been experimenting on small lots with the addition of natural products aimed at preventing the defect. The most effective are the tannins of vegetable origin and totally free of allergens. The results are interesting, but we will continue our research activity, comparing ourselves with colleagues, from Franciacortas and beyond, to solve together a problem that is now far more widespread than the well-known corky smell”, concludes the winemaker.

Alessandro Schiavi