Here is a brief history of the fortified wine, a guide to the different varieties – and the best buys
I'm being whirled energetically around a granite vat, knee-deep in grapes, while a small man beats a tambourine with gusto. I've drunk some port and I'm feeling slightly hysterical. It is harvest time in the Douro Valley in Portugal and we're tramping the newly picked fruit that will become some of the region's fortified wine, much loved around the world – and especially in the UK at this time of year.
Quinta do Vesuvio, owned by the Symington family, is one of the few remaining estates to use people rather than machines for grape-treading. About 50 of the seasonal pickers earn a bonus ending the day's work submerged in these lagars for four hours. In the first stage (the corte), lines are formed and we march to a called rhythm. This breaks the grapes gently and uniformly, extracting the skins' deep colour and tannins. Then it's liberdade: the band strikes up and the crowd – among them couples, young and old – are free to dance and stroll the lagar. It is great fun, but after an enthusiastic hour I stumble out, dizzy and exhausted.
Luckily, others have more stamina. There is no time to waste, as the fermentation has to be interrupted 36-48 hours after it starts by the addition of natural grape spirit to the "must" (fermenting grape juice): one part spirit to four parts must. This arrests the process, preserving about half the grape's natural sugars for port's characteristic rich and fruity finish. The grape spirit brings the strength of port up to 20% by volume – thus "fortified wine".
It is a stressful time for Paul Symington, who eyes the September skies nervously for the forecast storm that threatens his unpicked grapes. It is beautiful and isolated up here in the Douro – a Unesco heritage site, and the largest area of mountain vineyard in the world. Steep walls of schist rise dramatically from the river, making mechanised picking impossible. The region suffers meltingly hot summers and bitterly cold winters, conditions that produce small, thick-skinned grapes: the main varieties are touriga nacional, touriga franca and tinta barroca, producing the dense concentrated must required. It is challenging viticulture, which explains the industry tradition of families such as the Symingtons, with 13 generations' experience to call on in making port.
When the Grahams – a Scottish entrepreneurial family – first invested in the upper Douro valley, acquiring Quinta dos Malvedos in 1890, the Douro river was the sole means of transportation. The wine was loaded on flat-bottomed boats (rabelos) to wind its way 60-80 miles downstream to Porto (then Oporto). Standing at the lodge at Malvedos today, you can see the jutting rocks that would have made it a wildly treacherous journey.
Once it reached the cooling Atlantic breezes of Oporto, the wine was aged and blended in barrels and bottles in the riverfront lodges at Gaia, opposite the main city. And from here to export: much of it went to England, where it made a welcome alternative when conflicts (and punitively high taxation) disrupted the UK's relations with France in the late 1600s and early 1700s. Low import duty further encouraged trade and Gaia's cobbled streets and hillsides are still littered with billboards attesting to British influence – Croft, Cockburn, Taylor, Dow, Warre. Fortification was employed to avoid spoilage on the long trip home, and the resulting strong, sweet wine appealed to the English market.
It is still considered a very British drink, coming out with the stilton at Christmas. But, as the port buyer for Berry Bros & Rudd, Simon Field, points out, deeply discounted supermarket varieties undermine the category, meaning we miss more interesting varieties. "Tawny port is still underappreciated in the UK," he says. These aged ports are ubiquitous in Porto – I quickly became a convert and will be spending Christmas nursing a 20-year-old tawny, fondly remembering my time in the lagar whence it came.
White grapes make a sweet and a dry wine. It is a popular aperitif in Portugal, lengthened with tonic (one-third port to two-thirds tonic) for a rival to a G&T before dinner. It keeps for three weeks. Serve chilled to 8-10C with ice, lemon and mint, and pair with toasted almonds or olives.
Buy: Taylor's Chip Dry Port (£12).
A good entry-level port – affordable, accessible, fresh and fruity. Blended from the grapes of several harvests and aged for two to three years, it is bottled young and boasts the vibrant colour we've come to associate with port. Premium ruby reserve, blended from higher quality wines and barrel-aged for about five years, is still fruity but offers more complexity. It keeps for about a month; serve at 16-18C and pair with cheese or dark chocolate.
Buy: Graham's Six Grapes (£12.75) or Cockburn's Special Reserve (£10.99).
Tawny starts off the same colour as ruby but, aged in oak barrels, fades to a tawny, golden brown, and swaps that fruitiness for a nutty, caramel edge. True tawny comes in 10-, 20-, 30- and 40-year-old versions – the average age of the wine (a blend of different years). It keeps for a good month. Serve at 12-14C with fruit, cheese and desserts.
Buy: Warre's Otima 10-Year-Old Tawny (£11) or Graham's 20-Year-Old Tawny (£25).
Vintage and late-bottled vintage (LBV)
Both are made from a single year's harvest but vintage is the real deal, with the price tag to match. Taken from the best grapes of the best harvests and declared as "vintage" (about three times a decade), it is then stored for 18–24 months in oak vats before bottling, and reaches its prime a few decades later, having aged in the bottle. One for investors and fine wine lovers: once open, consume within two days.
Buy: Dow's, Fonseca, Graham's, Noval and Taylor's, all upwards of £40, depending on the year and the producer.
LBVs also specify the year of vintage, will have been barrel-aged for four to six years and are closest to vintage in style, though fruitier, lighter-bodied and far cheaper. The unfiltered can be drunk right away without decanting (if it doesn't specify on the label, it's unfiltered) and will keep for two weeks or more.
Buy: Graham's and Taylor's 2008 LBV (£11–12).
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image: © jason gessner