Port is a fortified wine from the Douro Valley of northern Portugal. Claiming to be the oldest demarcated vineyard area in the world, it was granted its appellation by royal decree in 1756 (though both Tuscany and Tokaji make similar claims). The Douro region is protected from the Atlantic winds and humidity of western Portugal by the Serra do Marão mountains. Being so sheltered, rainfall is quite low by Portuguese standards, so summers are hot and dry and winters are cold.
Although more than four dozen different grape varieties are allowed in the production of port, the following five red-skinned varieties are widely considered the best: Touriga Nacional, with a powerful body and tannins best for vintage Ports; Touriga Francesa, which brings a smooth, rounded texture with soft tannins and a delicate aroma; Tinta Roriz, a variant of Rioja’s Tempranillo known for its firmness and structure; Tinta Barroca, with a very high sugar content and an intensity and structure rivalling Nacional; and Tintã Cão, which has all but disappeared due to miniscule yields, but is noted for providing texture and structure rather than for intensity.
Grapes are picked at around 12° to 14° Baumé and fermented for only 36 to 48 hours. The extraction of colour and tannins are essential to the ageing properties of the wines, and in some of the finest vineyards this is still achieved by the traditional treading of the grapes. After about half of the sugars have been transformed into alcohol, the wines are fortified with pure grape spirit (77% a/v). Most wines are taken to Vila Nova de Gaia on the south bank of the Duoro to mature in gentler conditions. Provenance might dictate the fundamental quality and style of port, but there are two important factors: whether or not the wine is from a single vintage and whether the majority of it was aged in bottle or in wood.
Port is made in many different styles, primarily divided into two categories according to how it was aged.
After only a short time in wood, Vintage and Single Quinta Ports are bottled without filtration and aged in the bottle. These are the ports deemed to be the best, and they age well in the bottle but deteriorate quickly once opened.
Vintage Port – The best of the best, blended from various vineyards in one superior ‘declared’ year. Aged for only two years in cask before bottling, Vintage Ports age slowly in the bottle for between 15-30 years.
Single Quinta Port – Created from a single ‘Quinta’, or vineyard property, it is aged in wood for only two years and bottled without filtration just like a Vintage Port. It provides a vintage-style wine in years when no vintage has officially been declared. Single Quinta Vintage Ports take 8 to 10 years to develop their full potential. Single Quinta Ports are different from Vintage Ports in that they convey both the terroir of the property and the character of a single year.
Wood-aged ports are aged in wood before they are bottled and released. They are filtered before bottling and therefore do not need decanting.
Ruby Port – Only aged in large wooden vats for two to three years, Ruby Ports are young, full-bodied and brash. Generally, they are aged in the much hotter Douro Valley and care is taken to prevent oxidation. This practice preserves the deep ruby colour and the powerful fruit characters of youth.
Character Port – Just like a non-vintage Champagne, port producers endeavour to blend to a house style that only changes minimally. Character Ports are such wines, usually blended from Ruby Ports from various years and vineyards. Generally, they are aged for four to six years in wood where they retain their fresh, ruby red colour.
Aged Tawny Port – Ageing high-quality Ruby Ports in wood for many years softens the tannins, and natural oxidation changes the colour from bright red to a tawny colour. Although an age may be shown on the label, it is an average age, not an absolute age. Aged Tawny Ports should not be kept for years, but consumed near the date on the label.
Late Bottled Vintage Port (LBV) – Contrary to true Vintage Ports, these wines spend much longer in a cask. Upon their release they are fully matured.
White Port – These are made exclusively from white grapes and generally bottled at about three years old, though a few producers are reintroducing the more traditional 10-year-old White Port and even a 25-year-old is now available – although the rules forbid an age statement on the label. Dry White Port usually means off-dry and White Port indicates sweet. White Port is best consumed cool to cold.
NOTE: Old bottles of port can be difficult to open by pulling the cork as the cork may crumble; it is a lot cleaner to use port tongs. You superheat the tongs and clamp them around the bottle neck below the cork. Remove the tongs, chill the neck immediately (ice towel), and then you can literally lift the now cleanly split top of the neck off, leaving no glass (or cork) behind in the bottle.