The major historic memento of the region took place between 1755 and 1761, with the institution of the Fundação da Companhia Geral da Agricultura das Vinhas do Alto Douro (General Company Foundation of Agriculture of the Upper Douro Vineyards), on September 10th, 1756, and the creation of the first demarcated region of the world. During these years at the behest of the Prime Minister and Marquis of Pombal, 201 stone markers with the Feitoria
designation were placed (Figure No. 25) in order to delimit the region. The first records of wines with the Vinho do Porto
designation date back to 1760.
The Douro Demarcated Region has 250 hectares of total area, divided into three sub-regions: Baixo Corgo, Cima Corgo and Douro Superior (Figure No. 8). The geology of the region is characterized by greywacke schist soils and in some places of granitic origin. These soils have been worked for centuries by human action in order to create a vineyard planting base and other crops in the rock mass formations. The macro climate of the region is heavily influenced by the mountain ranges of Marão and Montemuro, which act as a natural barrier to the humid winds from the west. The winters are very cold and rigorous and summers are very hot. Rainfall is also a factor that varies widely given the geographical complexity of the region. The highest values of rainfall vary between 1200 mm and 380 mm per year, at different points in the same region. One of the most important agents for the cultivation of the vine is sun exposure. The fact that this is a mountainous region, causes the Sun's viewing period varies greatly from plot to plot.
To prove one more quality control effort, a system of quality assessment of vineyard plots was created, even more rigorous than the Clos
of Burgundy, with a scoring system that integrates location, slope, altitude, rock mother, sun exposure, the gross elements, shelter, cultural operations, performance, vine varieties, planting density, the plantation system and the age of the vines.
This set of factors, properly assessed and qualified numerically, give rise to 6 qualifications (Table No. 4) different, representing the letter A, the best classification, succeeding the B, C, D, E and F, with the latter to represent the lowest score of the scale.
This is a unique system in the world and evaluates, by a numeric value, the qualitative and quantitative selection of each plot. It is certainly a method that contributes to the definition of the quality of the wines produced in the region.
The vines that give rise to Vinho do Porto are mostly planted on ledges built on mountain slopes of the Alto Douro region, difficult to access and where the steepness is a factor that affects the viticulture work. The varieties used for the preparation of the Vinho do Porto are Portuguese native grape varieties. The best known are the Tinta Amarela, Touriga Francesa, Touriga Nacional, Tinta Roriz, Tinta Barroca and Tinto Cão, in red wines, and the White Port wines, Malvasia Fina, Gouveio, Viosinho and Donzelinho; there are also many other grape varieties but with a lower planted area.Vinho do Porto
can be divided into four broad categories or families: Ruby
(White) and Rosé
(Table No. 5).
The family of Ruby's is characterized by wines which seek to keep the red colour, the fruity aroma and the strength of a young wine. Within this family there are categories of Ruby, Reserva, Late Bottled Vintage (LBV) and Vintage. Qualified wine LBV and Vintage are wines that have the potential to age for long years without a deadline given its great ageing potential.
The family of Tawny's is characterized by the association of different wines at different degrees of ripeness, aged in an oxidative environment, in barrels or casks. These wines have a change in their colour, framed in the subclasses of red-tawny colour, tawny and tawny light. The aromatic bouquet of this family is quite marked by dried fruit and wood notes, features stressed due to the wine antiquity. The categories within this family are Tawny, Tawny Reserva, Tawny com Indicação de Idade (Tawny with indication of age) (10 years, 20 years, 30 years and 40 years, blend resulting of different wines from different) and Colheita (from only one year of harvest). Tawny's are wines that result from the combination of different batches of different harvest years, with the exception of Tawny's Colheita. The family of White Port comes in many styles, particularly associated with periods of greater or lesser duration of ageing and varying degrees of concentration of sugars as a result of their development process. In this family of wines a floral bouquet on the nose and a complex alcohol on the palate are characteristic.
The family of Rosés is obtained by a short maceration of red grapes and wine making with white wine. The oxidative phenomena in this style of wine to preserve its colour is not promoted. This family of wines is characterized by very soft and light notes of cherry, raspberry and strawberry.Vinho do Porto
is the best known Portuguese wine in the world and also the one for which there more attempts to reproduce or copy. What is important to note here is the necessary verification of authenticity, so that the copy does not devalue the product and misleads the consumer.