An introduction to Port

Port starts with grapes grown in the heat of the Douro valley usually on terraces cut into the steep hillsides. The region runs from just over the mountains from Porto, right up to the Spanish border.

Whereas most wines are made from a limited palate of grapes, Port has dozens, maybe even hundreds, of different varieties. In the past these were planted in a hodge-podge with growers probably not aware of which varieties they had. Nowadays, viticulture is more systematic though some producers are returning to the old system. The best known Port grapes are touriga nacional, touriga Francesa, tinto roriz (known in Spain as tempranillo), tinta cão, and tinta barroca. There are also white grapes including gouveio, malvasia Fina, moscatel galego, rabigato, and viosinho.

After harvesting, which usually takes place in September, the grapes are taken to wineries around the Douro valley. There they are crushed. Traditionally this was done by foot in great stone lagars, and some wineries still practise this, but most wineries are now mechanised. The aim is to extract as much flavour, tannin, and colour out of the grapes without crushing the pips which would release bitter aromas. Oddly enough, human feet are perfect for this. The crushed grapes are then left to ferment either with cultured or natural yeasts.

After about two or three days, high strength grape brandy (77% ABV) known as aguadiente is added to the still-fermenting wine, about one part brandy to five parts wine. This kills the yeasts and stops fermentation. You are left with an intensely flavoured and coloured sweet wine of about 19-20%.

Traditionally, Port was then brought down to age in the cooler climate of Vila Nova de Gaia, opposite the city of Porto, where most of the Port houses had their warehouses. Nowadays, however, thanks to air conditioning and better transport. Much of the ageing and blending takes place in the Douro valley itself.