This was originally published on oneblockwest.com.
Among diners in the restaurant and even among the servers, there is a good bit of confusion about Port. It seems nobody is exactly sure how it is made or what the differences between the kinds are.
Port is one of the oldest recognizable wines in the world. If you were to go back to Portugal in the latter half of the 17th century, you would find sweet fortified wines that you would recognize, although the name Port didn’t evolve until much later.
The name Port is an anglicization of the town of Oporto, the port from which Port is shipped, on the Atlantic Ocean at the mouth of the Douro river in northern Portugal. Although the wine has been traditionally matured and bottled in Villa Nova da Gaia, across the river from Oporto, the wines are made a long way upriver in the upper Douro, from the east-west center of the country to the eastern border with Spain (where the river is known as the Duero as in the Ribera del Duero DO).
Today as ever, the wines are vinified on the quintas (the estates) upriver where the grapes are grown. Then the wines are put in casks called pipes and sent downriver to the various lodges in Villa Nova da Gaia where they are matured, and thence after shipped to the world, primarily northern Europe. Since 1986, the wines no longer have to be matured and bottled in Villa Nova and we are starting to see many fine wines matured and bottled on the various quintas, of which there are thousands, many privately owned.
The restrictions on maturation and bottling in Villa Nova were put in place by the large port shippers to control the trade: small producers could not afford to build a lodge in Villa Nova in which to mature and bottle their wines. They were forced to sell their wines to one of the bigger houses.
Port starts off life like most wines, undergoing the usual pressing and fermentation, except that winemakers do not try to slow the fermentation by keeping the juice cool as they do in other hot weather climates. Fermentation of port is often very warm. The sweetness comes in because the winemakers do not allow the fermentation to complete: they stop it by adding aguardente, neutral grape alcohol, in a process called fortifying the wine. Once the alcohol level gets above 15% or so, the yeasts responsible for fermentation are killed, leaving unfermented sugars intact, hence the wine is sweet.
Most winemakers fortify their wines when the sugar level falls to about 90g per liter of juice by adding 110 liters of alcohol to 440 liters of wine (the Port pipes hold 550 liters). To make a drier port, they let the fermentation go longer and add less alcohol (the longer the natural fermentation, the higher the base alcohol level). To make a sweeter port, they stop the fermentation earlier and add more alcohol.
The styles of port are very confusing if you try to read the labels on the bottles. The best rule to remember is that in addition to a port made solely from white grapes (called white port), there are basically only two styles of red port: ruby and tawny. Both these names are taken from the color of the finished product and if you look at both in a glass, it is immediately obvious which is which.
Once the port is fortified, it is then placed in pipes to age. How long it ages governs whether it is a ruby or a tawny. Rubies spend little time in barrel and maintain their youthful color, fruitiness, and vibrancy in bottle where they are no longer exposed to oxygen (a reductive environment). Tawnies, on the other hand, spend a long time (8 to 50 years or more) in barrel, oxidizing further and further. As red wine oxidizes, it turns browner and paler and takes on nuttier flavors. Where rubies are bright and fiery, tawnies are mellow and nutty. Different styles for different folks.
There are further subdivisions, especially within the ruby style. A normal ruby will see between zero and four years in barrel and will be blended from several vintages. A late bottled vintage (LBV) will see between 4 and 6 years in barrel and will be the wine of a single vintage. There is a move afoot to call LBVs reserve ports. A vintage port legally sees less than two years in barrel and is the product of a single vintage, a vintage that the port shippers decide is especially worthy. Vintage ports can take decades to mellow into fine drinking wines. As an example, my 1977s are just barely ready to drink and will age well beyond my lifetime.
We offer many different ports at One Block West, often pairing the nutty tawnies with nut-based desserts and the rubies with chocolate. They're both great matches.