From the Latin pruina, frost. It is a seedy and whitish coating of leaves, stems and fruits in some vegetables similar to the frost of winter mornings. Now that we are harvesting, we observe this mantle, similar to the fogging of a glass fresh from the freezer, on the skin of the grapes that protects them from the sun's rays, from the rain and from the attack of insects. In it also lie the yeasts that carry out the fermentation of the wine.
