PORT

Port wine

Port wine (also known as Vinho do Porto, Portuguese pronunciation: , Porto, and often simply port) is a Portuguese fortified wine produced exclusively in the Douro Valley in the northern provinces of Portugal. It is typically a sweet, red wine, often served as a dessert wine though it also comes in dry, semi-dry, and white varieties. Fortified wines in the style of port are also produced outside Portugal, most notably in Australia, South Africa, Canada, India, Argentina, and the United States. Under European Union Protected Designation of Origin guidelines, only the product from Portugal may be labelled as port or Porto. In the United States, wines labelled “port” may come from anywhere in the world, while the names “Dão”, “Oporto”, “Porto”, and “Vinho do Porto” have been recognized as foreign, non-generic names for wines originating in Portugal.

Region and production:

Port is produced from grapes grown and processed in the demarcated Douro region. The wine produced is then fortified by the addition of a neutral grape spirit known as aguardente in order to stop the fermentation, leaving residual sugar in the wine, and to boost the alcohol content.
The fortification spirit is sometimes referred to as brandy but it bears little resemblance to commercial brandies. The wine is then stored and aged, often in barrels stored in a cave (pronounced kahv and meaning “cellar” in Portuguese) as is the case in Vila Nova de Gaia, before being bottled.
The wine received its name, “port”, in the latter half of the 17th century from the seaport city of Porto at the mouth of the Douro River, where much of the product was brought to market or for export to other countries in Europe.
The Douro valley where port wine is produced was defined and established as a protected region or appellation in 1756, making it the oldest defined and protected wine region in the world. Chianti (1716) and Tokaj (1730) have older demarcation but no regulation associated and thus, in terms of regulated demarcated regions, Porto is the oldest.
The reaches of the valley of the Douro River in northern Portugal have a microclimate that is optimal for cultivation of olives, almonds, and especially grapes important for making port wine. The region around Pinhão and São João da Pesqueira is considered to be the centre of port production, and is known for its picturesque quintas—farms clinging on to almost vertical slopes dropping down to the river.

Wine regions

The demarcation of the Douro River Valley includes a broad swath of land of pre-Cambrian schist and granite. Beginning around the village of Barqueiros (located about 40 miles (about 70 km) upstream from Porto), the valley extends eastward nearly to the Spanish border. The region is protected from the influences of the Atlantic Ocean by the Serra do Marão mountains. The area is sub-divided into 3 official zones-the Baixo (lower) Corgo, the Cima (higher) Corgo and the Douro Superior.
• Baixo Corgo – The westernmost zone located downstream from the river Corgo, centered on the municipality of Peso da Régua. This region is the wettest port production zone, receiving an average of 900 mm, and has the coolest average temperature of the three zones. The grapes grown here are used mainly for the production of inexpensive ruby and tawny ports.
• Cima Corgo – Located further upstream from the Baixo Corgo, this region is centered on the town of Pinhão (municipality of Alijó). The summertime average temperature of the regions are a few degrees higher and rainfall is about 200 mm less. The grapes grown in this zone are considered of higher quality, being used in bottlings of vintage and Late Bottled Vintage Ports.
• Douro Superior – The easternmost zone extending nearly to the Spanish border. This is the least cultivated region of Douro, due in part to the difficulties of navigating the river past the rapids of Cachão da Valeira. This is the most arid and warmest region of the Douro. The overall terrain is relatively flat with the potential for mechanization.[
Grapes
Over a hundred varieties of grapes (castas) are sanctioned for port production, although only five (Tinta Barroca, Tinta Cão, Tinta Roriz (Tempranillo), Touriga Francesa, and Touriga Nacional) are widely cultivated and used. Touriga Nacional is widely considered the most desirable port grape but the difficulty in growing it and the small yields cause Touriga Francesa to be the most widely planted grape. White ports are produced the same way as red ports, except that they use white grapes— Donzelinho Branco, Esgana-Cão, Folgasão, Gouveio, Malvasia Fina, Rabigato and Viosinho. While a few shippers have experimented with Ports produced from a single variety of grapes, all Ports commercially available are from a blend of different grapes. Since the Phylloxera crisis, most vines are grown on grafted rootstock, with the notable exception of the Nacional area of Quinta do Noval, which, since being planted in 1925, has produced some of the most expensive vintage ports.
Grapes grown for port are generally characterised by their small, dense fruit which produce concentrated and long-lasting flavours, suitable for long aging. While the grapes used to produce port produced in Portugal are strictly regulated by the Instituto do Vinho do Porto, wines from outside this region which describe themselves as port may be made from other varieties.

Transport

While port is produced from grapes grown in the Douro valley, until 1986 it could only be exported from Portugal from Vila Nova de Gaia near Porto, Portugal’s second-largest city. Traditionally, the wine was taken downriver in flat-bottom boats called ‘barcos rabelos’, to be processed and stored. However, in the 1950s and 1960s, several hydroelectric power dams were built along the river, ending this traditional conveyance down the river. Currently, the wine is transported from the vineyards by tanker trucks and the barcos rabelos are only used for racing and other displays.

Properties

Port wine is typically richer, sweeter, heavier, and possesses higher alcohol content than unfortified wines. This is caused by the addition of distilled grape spirits (aguardente similar to brandy) to fortify the wine and halt fermentation before all the sugar is converted to alcohol and results in a wine that is usually either 18 to 20% alcohol.
Port is commonly served after meals as a dessert wine in anglo-Saxon countries, often with cheese; white and tawny ports are often served as an apéritif. In Europe all types of port are frequently drunk as aperitifs.

Styles

Port from Portugal comes in several styles, which can be divided into two broad categories:
• Wines that have matured in sealed glass bottles, with no exposure to air, and experience what is known as “reductive” aging. This process leads to the wine losing its colour very slowly and produces a wine which is smoother on the palate and less tannic.
• Wines that have matured in wooden barrels, whose permeability allows a small amount of exposure to oxygen, and experience what is known as “oxidative” aging. They too lose colour, but at a faster pace. They also lose volume to evaporation (angel’s share), leaving behind a wine that is slightly more viscous.
The IVDP (Instituto dos Vinhos do Douro e Porto) further divides port into two categories: normal ports (standard rubies, tawnies and white ports) and Categorias Especiais, special categories, which include everything else.

HISTORY OF PORT WINE

The first vineyards in Douro were planted in the thirteenth century during the reign of Dom Diniz.
Until the 17th century, French wines were infinitely more popular than wines from Portugal. However, by the end of the 17th century, relations between Britain and France had deteriorated so badly that the British government decided to impose heavy import duties on French wines, and the discovery was made that the wines from the Douro valley were to the taste of the British. The British had forsaken the wines of Bordeaux in favour of those coming from the Douro valley.
Port’s big impact came during the French Revolution and the Napoleonic Wars that followed. Since French wine was more or less unobtainable, the British took to port like ducks to water. Soon British wine merchants migrated to Portugal and established the famous port houses.
Port can legally still only be produced in the Douro region within boundaries firmly delineated by the Portuguese government. It remains to this day the centre of much of the world’s production.
Three main factors account for the difference between one port and another:
- The quality of the grapes and the soil in which they are cultivated
- The blend of wines selected for each style of port
- Whether the port is matured in the bottle or in a wooden cask

1. SOILS AND CLIMATE

It is difficult to imagine a more challenging place to grow grapes and, at first sight, hard to conceive how the banks of the Douro ever came to be planted with vineyards.
Forming a deep cleft in the rock, the river Douro runs from east to west and is therefore the natural axis for the region. The river itself, dammed to form a series of placid Finger Lakes, flows at an altitude of between 60 and 140 metres above sea level. The terrain either side of the Douro is irregular in the extreme with deeply incised tributaries draining the mountains, which rise in places to over 1000 metres on the edge of the region. Half of the region’s vineyards are planted on slopes.

The Douro’s soils are naturally rich in Potassium and magnesium but tend to lack calcium and boron, causing a condition known locally as moromba. This was originally thought to be a virus, but is now successfully treated by applying borax to the soil. The proportion of organic material in the Douro’s soils is low and regular application of both organic and inorganic fertilisers is necessary to correct the imbalance of nutrients.
The Northwest of Portugal receives during the winter a lot of rain. The region of Douro is divided in three sub regions, each of which has it its own meso-climate and tends to produce a very different style of Port.

2. VINEYARDS AND QUINTAS

Planting a vineyard in the Douro is rather like planning a new town. All the gradients have to be considered in detail if the property is to function efficiently over a commercial life.
The feature that all the vineyards have in common is the initial deep ploughing or ripping of the earth to create a course top soil roughly 1-1.3 metres in depth. These steps like terraces are called socalcos or patamares.

The use of tractor changes the style of these terraces. The early patamares have been planted with up to 2.2 metres between each of row of vines. This allows a small caterpillar tractor to circulate between the row of vines to carry all the bags of grapes.

The vineyard classification is the basis for the authorisation which regulates the amount of Port that may be produced in any one year. Taking in account the previous year’s sales and stocks of Porto held by the shippers, the Instituto do Vinho do Porto (Port Wine Institute) determines the total amount of grape that must be fortified to make Porto. The vineyard plot within the Douro is graded according twelve different physical variables:
- Altitude
- Locality
- Productivity
- Soil Type
- Vine Training
- Grape Varieties
- Angle of inclination of the slopes
- Aspect and exposure
- Stoniness
- Age of the Vines
- Shelter
- Vine Density
On the basis of the vineyard classification a licence would be issued permitting the grower to produce a certain amount of Port per thousand vines.
The building block of the Douro is the quinta. All the quintas have the adega (vinery), armazem (storage).

4. MAKING PORT- TRADITION AND TECHNOLOGY

In the past, the grapes were carried out entirely by hand. Grapes were traditionally cut into large, coarse woven baskets with capacity up to 75 Kg at a time. These would then be carried to the adega by a regimented line of pickers. Although baskets are still used by some smaller growers, nowadays they are loaded on to trailers and towed to the adega by tractor. The majority of grapes are now transported to the winery in 1000 Kg steel bins known as dornas.

Baumé (a measure of the concentration of grape sugars), pH and total acidity are crucial readings but tasting grapes or juice are important for the determination of the optimum ripeness. All grapes destined for the production of Port must legally be above 11 degrees baumé.
The key to the production of a quality red Port is in the vigorous extraction of colour and flavour compounds found in the skins of the grapes. The deep hue, firm tannin structure and ripe flavours that characterise a young, premium quality Port have to be extracted before the fermentation is prematurely arrested by the addition of grape spirit known as aguardente.

TRADITION

The place where is extracted the colour and flavour from the Port grapes is the lagar. This is a square stone tank made from granite or cement, usually no more than a metre in depth with a capacity varying between 15 and 25 pipes (8000-14000 litres).
Over the course of a day’s picking, the lagar is filled to within 15 to 20 centimetres of the brim. As the sun begins to set the pickers return to the adega and start treading the grapes in the lagar. For the first two to three hours, the treaders link arms and march slowly back and forth; the soles of their feet crushing the grapes gently against the stone floor of the lagar.

Depending on the temperature at which of the grapes reach the vinery, fermentation will begin quite soon after treading, possibly during the night. The action of human legs and feet helps to warm the must. Ideally the grapes will arrive at the adega registering temperature around 20ºC, rising to 28-30ºC at the height of fermentation.
Once a sufficient amount of colour and flavour has been extracted and sugar level fallen to around 7 or 8 baumé, the partially fermented must is run off the skins and mixed with the fortifying aguardente. Blended in a proportion of roughly 20 per cent aguardente to 80 per cent grape must, the alcohol is raised to a level where the fermentation yeasts are unable to survive. The result is a deep, dark, naturally rich wine with between 80 and 120 g/l residual sugar and a alcoholic strength of 19-20 per cent by volume: the embryonic Port.

TECHNOLOGY

The process called Autovinification powered by a natural build-up of carbon dioxide in the system is the more vigorous and the most used. Nowadays, large wineries are fully automated from star to finish. As soon as a consignment of grape arrives at the winery, a core sample is taken from each of the bins and the must weight or baumé is recorded by refractometer to determine the amount of fermentable sugar. After the bins has been weighed it is tipped into a reception hopper from where a large screw (‘without end’) conveys the grapes to a crusher-destemmer, which removes at least a proportion of the stalks from both red and white grapes. Before the crushed grapes reach the fermentation tank or autovinifier, the must is dosed with sulphur dioxide at levels of between 40 and 150 mg per Kg. Most wine-maker will adjust the acidity of the must at this stage to around pH 3.6-3.7 by adding the appropriate amount of tartaric acid.

Measurement of the acidity

The preoccupation with the ways of crush the grapes in the lagares have led to a number of attempts to simulate the gentle action of the human foot with pistons. A temperature controlled stainless steel vat equipped with programmable pistons is installed in some quintas.

Pistons to crush the grapes

When they were first developed, most autovinification vats were cubic in shape and built from epoxy-lined reinforced concrete with a capacity similar to that of the traditional lagar. A number of modifications were made to the autovinification system, the most significant of which was the introduction of temperature control.
The basic functionality of the autovinification system is explained:
- The vat is filled of full capacity;
- As the fermentation begins carbon dioxide is given off and the pressure builds up inside the tank. This forces the fermenting must up an escape valve which spills into an open holding tank on top of the vat;
- Once a certain pressure has built up inside the autovinifier, the carbon escapes though a calibrated hydraulic valve. No longer supported by the pressure inside the vat, the fermenting must falls back down the central autovinification unit by force of gravity. At the same time the hydraulic valve resets itself ready for the pressure to build up and the cycle to begin again.

As in the traditional way, all Port is fortified to a strength of between 19 and 22 per cent of volume. In a process called as encuba, the wine is typically run off when approximately 4 or 5 per cent of natural alcohol has been produced from the fermentation and mixed with grape spirit or aguardente in a proportion of 20 percent. The blending of aguardente is generally carried out by pumping a measured quantity of spirit into wooden, cement or stainless steel holding tank simultaneously with the free run juice.

5. MATURATION

All Port wines spend their first winter in the Douro during which time they fall bright as minute yeast cells, grape solids and tartrates settle to the bottom of the vat, helped by the cold weather. The young wines are racked and drawn off the sediment, analysed and adjusted where necessary. This provides the opportunity of the first selection and classification.
The atmosphere of Porto and VN Gaia is eminently suitable for the maturation of wine and it is here rather than in Douro that the Port shippers inevitably choose to set up their cellars. In the past days, the Port wine was transported to Porto by a boat called barco rabelo. These boats were gradually abandoned and the transportation actually is by train.

The wine matures in a loja, a shop or cellar store. Most of the wines ages in wooden vats and casks holding as much as 100 000 litres to casks of around 600 litres. They function as vessels for ageing where the permeability of the wood permits a gradual, controlled oxidation of the contents. Wines destined for a bottling after two or tree years (Vintage) are partly aged in wooden vat and partly kept in stainless steel to preserve the primary character of the fruit. Wines set aside to become old Tawnies are transferred to smaller lodge pipes to enhance the oxidative character of the wine.

6. RACKING

The process of racking is an extremely labour-intensive part of the annual cycle of cellar work. It involves the removal of clear wine from the sediment or less that have settled at the bottom of the cask or vat. Left in the wine, the less will generate off-flavours.
Ports are typically racked three times in the first year, twice in the second and annually thereafter. In the case of old wines, pipes or casks are decanted progressively, starting from the top row.

7. CLARIFICATION AND FILTRATION

Racking alone is sufficient to eliminate heavier insoluble particles from a young Port but is does not remove inherently unstable material found in solution that could precipitate after the wine has been bottled. Most wines are therefore clarified using fining agents like gelatine, bentonite, egg white and casein.
Most of the larger Port shippers have invested in continuous systems, which chill the wine and pass it continually though a crystallising seeded with potassium bitartrate. In each case, the wines are filtered after the stabilisation process using diatomaceous earth followed by sheet and/or membrane filters.

8. QUALITY CONTROL

The Port Wine Institute has a well-equipped laboratory and offers its services to smaller shippers. The Institute also has its rigorous quality control producers but a number of smaller shippers without their own laboratories are still sitting on a potential bacterial time bomb.
Despite the obligatory and increasingly rigorous assessment by the Institute, a number of inconsistent and occasionally downright faulty wines, essentially from other countries, continue to reach export markets.

Styles of port:

Tawny port

Tawny ports are wines, made from red grapes that are aged in wooden barrels, exposing them to gradual oxidation and evaporation. As a result, they gradually mellow to a golden-brown colour. The exposure to oxygen imparts “nutty” flavours to the wine, which is blended to match the house style.
Tawny ports are sweet or medium dry and typically consumed as a dessert wine.
When a port is described as tawny, without an indication of age, it is a basic blend of wood aged port that has spent at least two years in barrels. Above this are tawny with an indication of age which represent a blend of several vintages, with the nominal years “in wood” stated on the label. The official categories are 10, 20, 30 and over 40 years. The categories indicate a target age profile for the ports, not their actual ages, though many people mistakenly believe that the categories indicate the minimum average ages of the blends. It is also possible to produce an aged white port in the manner of a tawny, with a number of shippers now marketing aged white ports.

Colheita

A tawny port from a single vintage is called Colheitas. Instead of an indication of age (10, 20…) the actual vintage year is mentioned. However, they should not be confused with vintage port (see below): whereas a vintage port will have been bottled about 18 months after being harvested and will continue to mature, a Colheita may have spent 20 or more years in wooden barrels before being bottled and sold. A number of white Colheitas have also been produced.

Garrafeira

Garrafeira is an unusual and rare intermediate vintage dated style of port made from the grapes of a single harvest that combines the oxidative maturation of years in wood with further reductive maturation in large glass demijohns. It is required by the IVDP that wines spend some time in wood, usually between three and six years, followed by at least a further eight years in glass, before bottling. In practice the times spent in glass are much longer. The style is most closely associated with the company Niepoort, although others do exist. Their dark green demijohns, affectionately known as bon-bons, hold approximately 11 litres each. Some connoisseurs describe Garrafeira as having a slight taste of bacon, although many people will neither notice nor understand such a description; the reason being that, during the second phase of maturation, certain oils may precipitate, causing a film to form across the surface of the glass that can be tasted by those who are accustomed to the difference between Garrafeira and other forms of port.
Confusingly, the word Garrafeira may also be found on some very old tawny labels, where the contents of the bottle are of exceptional age.

Ruby port

Ruby port is the cheapest and most extensively produced type of port. After fermentation, it is stored in tanks made of concrete or stainless steel to prevent oxidative aging and preserve its rich claret color. The wine is usually blended to match the style of the brand to which it is to be sold. The wine is fined and cold filtered before bottling and does not generally improve with age.
Reserve or vintage character
Reserve port is a premium ruby port approved by the IVDP’s tasting panel, the Câmara de Provadores. In 2002 the IVDP prohibited the use of the term “Vintage Character”, as the wine had neither a single vintage (usually being a blend of several vintages of ruby port) nor the typical character of vintage port.

Rose port

Rose port is a very recent variation on the market, first released in 2008 by Poças and by Croft, part of the Taylor Fladgate Partnership. It is technically a ruby port, but fermented in a similar manner to a rosé wine, with a limited exposure to the grape skins, thus creating the rose colour. It has enjoyed little critical acclaim.

White port

White port is made from white grapes and can be made in a wide variety of styles, although until recently few shippers have produced anything other than a standard product. Ordinary white ports make an excellent basis for a cocktail while those of greater age are best served chilled on their own. There are a range of styles of white port, from dry to very sweet. When white ports are matured in wood for long periods, the colour darkens, eventually reaching a point where it can be hard to discern (from appearance alone) whether the original wine was red or white.

Late bottled vintage (LBV)

Late bottled vintage (often referred to simply as LBV) was originally wine that had been destined for bottling as vintage port, but because of lack of demand was left in the barrel for longer than had been planned. Over time it has become two distinct styles of wine, both of them bottled between four and six years after the vintage, but one style is fined and filtered before bottling, while the other is not.
The filtered wine has the advantage of being ready to drink without decanting and is usually bottled in a stoppered bottle that can be easily resealed. However many wine experts feel that this convenience comes at a price and believe that the filtration process strips out much of the character of the wine.
Unfiltered wines are mostly bottled with conventional driven corks and need to be decanted. After decanting they should be consumed within a few days. Recent bottlings are identified by the label wording “unfiltered” or “bottle matured” or both. Before the 2002 regulations, this style was often marketed as ‘”traditional”, a description that is no longer permitted.
LBV is intended to provide some of the experience of drinking a vintage port but without the need for lengthy bottle aging. To a limited extent it succeeds, as the extra years of oxidative aging in barrel does mature the wine more quickly.
Typically ready to drink when released, LBV ports are the product of a single year’s harvest and tend to be lighter bodied than a vintage port. Filtered LBVs can improve with age, but only to a limited degree; whereas the unfiltered wines will usually be improved by extra years in the bottle. Since 2002, bottles that carry the words “bottle matured” must have enjoyed at least three years of bottle maturation before release.
Crusted
Crusted port is usually a blend of port wine from several vintages, although single vintage crusted ports have sometimes been made in the past. Unlike vintage port, which has to be sourced from grapes from a single vintage, crusted port affords the port blender the opportunity to make best use of the varying characteristics of different vintages.
Crusted port is bottled unfiltered, and sealed with a driven cork. Like vintage port it needs to be decanted before drinking.
Although crusted ports will improve with age, the blender often seeks to make these wines approachable at a younger age than for his vintage ports. The date on a crusted port bottle refers to the bottling date, not the year the grapes were grown.
While crusted port is required to be aged in bottle for at least three years before it is released to the market, most producers keep the bottles for considerably longer; so they are ready to be drunk when sold, and may be enjoyed by consumers who have no space to cellar bottles. This makes crusted port a popular and affordable alternative to vintage port.

Vintage port

Vintage port is made entirely from the grapes of a declared vintage year and accounts for about two percent of overall port production. Not every year is declared a vintage in the Douro. The decision on whether to declare a vintage is made in the spring of the second year following the harvest. The decision to declare a vintage is made by each individual port house, often referred to as a “shipper”.
The port industry is one where reputations are hard won and easily lost, so the decision is never taken lightly. During periods of recession and war, potential “declarations” have sometimes been missed for economic reasons. In recent years, some shippers have adopted the “chateau” principle for declarations, declaring all but the worst years. More conventional shippers will declare, on average, about three times a decade.
While it is by far the most renowned type of port, from a volume and revenue standpoint, vintage port actually makes up only a small percentage of the production of most shippers. Vintage ports are aged in barrels for a maximum of two and a half years before bottling, and generally require another ten to forty years of aging in the bottle before reaching what is considered a proper drinking age. Since they are aged in barrels for only a short time, they retain their dark ruby colour and fresh fruit flavours. Particularly fine vintage ports can continue to gain complexity and drink wonderfully for many decades after they were bottled. It is not unknown for 19th century bottles to still be in perfect condition for consumption.

Single quinta vintage port

Single quinta vintage ports are wines that originate from a single estate, unlike the standard bottlings of the port wine houses which can be sourced from a number of quintas. Single quinta bottlings are used in two different ways by different producers. Most of the large port wine houses have a single quinta bottling which is only produced in some years when the regular vintage port of the house is not declared. In those years, wine from their best quinta is still bottled under a vintage designation, rather than being used for simpler port qualities. In a sense, this kind of single quinta is a “second wine” of the regular vintage port and is typically sold slightly cheaper than the regular vintage Port. Graham’s Quinta dos Malvedos and Taylor’s Quinta de Vargellas are examples of this kind of port. Typically, this type of single quinta bears the name of both a major port wine house and the name of a quinta.
In recent times, there has also been an increase in the production and marketing of single quinta vintage port as high-end wines. Vintage port from small producers situated in the Douro valley are almost always single quinta wines and labelled as such. Some of the larger port wine houses also have introduced single quintas which are run as separate estates, rather than as a source of wine for the house’s main bottling. Symington Family Estates’ Quinta do Vesuvio is an example of this. Typically, this type of single quinta only bears the name of its quinta.
Much of the complex character of aged vintage port comes from the continued slow decomposition of grape solids in each bottle. However, these solids are undesirable when port is consumed, and thus vintage port typically requires a period of settling before decanting and pouring.