Portwine must come exclusively from the three production areas in the Douro Valley in northern Portugal (Baixo Corgo, Cima Corgo and Douro Superior). More than 40 grape varieties are authorised for the production of port wine, the most important being Tinta Roriz, Touriga Nacional and Tinta Barroca.
After the grapes are picked by hand, they are pressed and the must is used for fermentation. The fermentation is stopped by adding a wine distillate of about 80%vol. The moment when you add the wine distillate is crucial as it determines the remaining sugar, the sweetness of the port wine. Each port wine matures first for at least 2 years in wooden barrels.
Portwine has an alcohol content of between 19 and 22 % vol., so it can be stored for a long time.
Vintage Ports will be bottled after 2 years
Late Bottled Vintage Ports (LBV) will be bottled after 4-6 years
Colheita Ports will be bottled after a minimum of 7 years (sometimes they stay as long as 50-80 years or more in the barrel)