Between Port and hope, anything is possible. An inside look at one of the worlds most treasured wines: Port, part one.
Port is a fortified, (semi-)sweet wine from the world’s oldest regulated and demarcated wine region. The region was created with the establishment of the Companhia Geral da Agricultura das Vinhas do Alto Douro and demarcated in 1756. Port wine takes its name from the Portuguese city of Porto, the sea port at the mouth of the Douro, where the river flows into the Atlantic Ocean. Port wine, high in alcohol due to the addition of 77% neutral spirit during fermentation, is the result of the combination of soil, climate, grape varieties, its location determined by its steep hills along the meandering river Douro, the wine-making process and the way port matures or ages.
It was the geopolitics of Europe in the middle of the 17th-century, that caused the British to develop Portuguese wine into Port as we know it today. In 1678 Britain declared war on France and blockaded French ports. It was then that the British wine merchants turned to Portugal to find an alternative to the French wines. Travelling inland along the Douro River, the merchants found darker and more astringent red wines in contrast to those they had seen near the coast. In order to stabilize the wines for shipment to England, the merchants added brandy. The Methuen Treaty of 1703 is generally regarded as the beginning of the port trade.
There are three sub-regions of the Douro Valley – the Baixo Corgo, Cima Corgo and Douro Superior – all of which have vineyards on various altitudes with soils that get different exposure to the sun, varying amounts of rainfall and are planted with different grape varieties. Historically the vineyards in the Douro were planted with a mix of indigenous grape varieties and many vineyards still are. This mixed planting is referred to as a ‘field blend’. One winemaker told me once: “forget about the separate grape varieties, it’s the blend that counts.”
The Douro region, especially the Cima Corgo, is one of the most difficult areas to produce wines in the world. In spite of the The climate is harsh with blistering hot summers and cold winters and unpredictable weather forecasts. The soil is made up of granite and schist, a slate-like metamorphic rock that is rich in nutrients, but also has some useful water retention properties.
The vines used to be supported by century old terraces built with stone retaining walls (the terraces themselves are sloped, not level) the traditional socalcos, but repairing them after the often heavy winter rains is a tedious, money- and time-consuming job which led to the biggest change in the last 40 years in the Douro area, the replacement of traditional socalcos with patamares and vinha ao alto.
The first method, planting on the terraces, patamares, where the bulldozer cuts a flat, level surface onto the sides of the slopes, is chosen when the site is too steep and one cannot do vertical planting. The second method vinho ao alto or vertical planting, where one plants the vines up and down the hill side, offers the greatest level of mechanization.
The Quintas or vineyards in the Douro region are all graded according to a classification system that is based upon the physical characteristics of the vineyard and its potential to produce quality wines. The system is run by the Instituto dos Vinhos do Douro e Porto – IVDP. The IVDP authorizes for each grower the maximum amount of wine that may be fortified in a given year, depending on location, altitude, aspect, angle of slope, the soil and degree of stoniness, the micro climate, planting density, productivity, age of vines, type of grape varieties and type of training. Each factor has a minimum and maximum point score associated with it, and there are a total of 2,361 points available. An “A” grade vineyards must score over 1,200 points. A “B” vineyard scores between 1,001 and 1,200 points, and so on to “F”, the lowest grade. The IVDP classifies and rates the vineyards of the Douro every year, their classification dictates the production level and the price a grower can receive for their grapes for Port. The IVDP also regulates and controls the quality of DOC wines produced in the Douro.
Most Port is still matured in Vila Nova de Gaia and shipped from Porto, although some producers have built lodges in the Douro to age their ports as a result of the 1986 change in legislation allowing port to be shipped from anywhere in the Douro region and not just Vila Nova de Gaia.
Other changes include chilling the brandy before fortification; cooling the must before fermentation; researching and experimenting with various types of brandy used to fortify ports. Exploring new types of presses used for press wine is another development, besides the move toward the use of robotic lagares and automated piston plungers during vinification, which benefits the costs effectively, though treading grapes in lagares is still practised by the large producers of premium vintage ports, as well as by some smaller traditional houses.