Oporto Oporto wine is fortified with winery brandy, added during the fermentation to interrupt it, and to set its alcoholic content to the desirable value, also leaving some natural grape sugar free in the final product. The wine is kept in the Douro region during winter after the vine, being then transfered to the cellar where it is going to be gradually classified to give origin to different types of Porto Wines that are then bottled, conducted to the internal market and exported to all the world.