Port wine oxovitisin A, an oxovitisin, a type of pyranoanthocyanin with a 2-pyrone component. Port wine Port wine (also known as vinho do Porto, , Porto, and usually simply port) is a Portuguese fortified wine produced with distilled grape spirits exclusively in the Douro Valley in the northern provinces of Portugal. It is typically a sweet, red wine, often served as a dessert wine, though it also comes in dry, semi-dry, and white varieties. Fortified wines in the style of port are also produced outside Portugal, including in Australia, France, South Africa, Canada, India, Argentina, Spain, and the United States. Under European
Madeira wine up large (112 gal/423 l) casks of wine known as "pipes" for their voyages to India. The intense heat in the holds of the ships had a transforming effect on the wine, as discovered by Madeira producers when one shipment was returned to the island after a long trip. The customer was found to prefer the taste of this style of wine, and Madeira labeled as "vinho da roda" (wines that have made a round trip) became very popular. Madeira producers found that aging the wine on long sea voyages was very costly, so began to develop methods on the