How Rozes Port is made
Port wine has been made for many centuries in the harsh environment of the
Douro Valley in Portugal. In 1756, Marques de Pombal established the demarcation
of the Douro wine growing area. At the same time, he also laid down the inital
regulation on how Port wine should be produced to ensure the right quality.
These regulations have developed somewhat since then, reaching today's production method sometime during the second half of the 19th Century.
All Port wine is made from grapes growing in the Douro Valley, harvested in September and fortified with two-three days after the harvest (see also below). Then it is transported down the Douro River to Porto and Vila Nova de Gaia, where it is stored until ready for blending and shipment. In the following, this process is described in much further detail.
Grapes
There are 165 different registered grape types in the demarcated area of the
Douro Valley. In old times there was little concern for the mixing of these
varieties within the same parcel, as the Port wine was going to blended anyway.
Today, most new fields are created and maintained with a strict regime, making
sure that only one grape is growing in one field. Rozès is a strong
proponent of this approach, as it gives us the tool to make our distinctive,
high quality blend.
Even though there is 165 grape varieties, there are five main red varieties and four white varieties. The most used red grapes are Touriga Nacional, Tinta Roriz, Tinta Barroca, Tinta Cão, and Touriga Francesa, while the most common whites are Malvasia Fina, Viosinho, Donselinho, and Gouveio.
Red varieties
Touriga Nacional
Universally recognised as the finest grape for Porto, this variety was given
special attention and respect by writers as far back as the 18th century.
It is a vigorous, early maturing type with intense colour and aroma, notable
for longevity. Quite adaptable, it grows well in all three sub-regions and
flourishes even under very dry conditions.
Touriga Nacional, usually produces about 13% alcohol, has an excellent pH
or acid balance of 3.54, and a great number of polyphenols or aromatic components.
Although it can produce a perfectly balanced wine when used alone, it yields
only 1/3 to 1/2 as much as the other top four Douro Varieties, making its
exclusive use in a Porto wine economically impratical. Moreover, it is even
better when blended with other varieties.
The aroma contains hints of ripe fruits such as mulberry, raspberry and cassis
with floral overtones of violets and rockroses, and animal smells such as
musk and game.
Flavour is smooth, elegant and balanced, and while rich in tannins and fresh
acidity, the overall impression is of softness, finesse and complexity.
Tinta Roriz
Officially approved since 1800, this is the only top rated Douro variety to
be grown extensively outside Portugal. Recent research has shown it to be
similar or identical to the Tempranillo of Spain.
It combines high quality with good quantity, producing nearly 2 1/2 times
the juice of Touriga Nacional. Growing in large, compact clusters, a thick
skin makes it resistant to over-ripening.
Tinta Roriz yields well in all the sub-regions, but being sensitive to a shortage
of minerals, does best in rich soil. Quality shows considerable variation
depending on the year and location.
Average alcohol and pH are the same as for Touriga Nacional. Dominated by
wood, stemmy and herbaceous smells, in better years it also displays the floral
aroma of the rockrose and the fruitiness of mulberry and raspberry.
It is somewhat aggressive on the palate, due to preponderance of powerful,
thick tannins. The finish is long and fruity.
The overall impression is hard, astringent and powerful, with a certain brusqueness.
Tinta Barroca
This grape was already officially recognised prior to 1800 and was classified
in 1822 as being very good, but was not called Tinta Barroca until 1941. This
is now the only name under which it is known in the Douro.
Quite vigorous, with large, open clusters, it matures early, and in good years
is more prolific than any other top Douro variety.
The average alcohol is around 14% and it has low acidity with a factor of
around 3.7 on the pH scale.
The grapes are large with thin skins and for this reason cannot tolerate excessive
heat and direct sunlight. They flourish best at high elevations and on slopes
with northernly exposure, especially in the lower and upper Corgo sub-regions.
The character of the Tinta Barroca is almost diametrically opposed to that
of the Tinta Roriz: delicate, feminine, nonaggressive. When grown in a cool,
humid location it is low in tannin and seems soft and sweet. In warmer places
it produces more tannin which helps to balance its low acidity.
The Tinta Barroca adds elegance and aroma (it has a lot of phenols), and a
long, persistent, fruity finish with hints of cherry, raspberry and mulberry.
Tinto Cão
A variety already known in the 1600s, Tinto Cão was classified in 1791
as one of the best in Portugal, yielding a “coloured, strong and generous”
wine.
It is the least productive variety after Touriga Nacional. Growing in small
clusters with thick skins, it is resistant to heat and direct sunlight but
since the juice is prone to oxidation, it produces better in cooler places.
It does not have as much potential for deeply matured fruit as the other four
varieties.
When grown in a cool place, the alcohol level is usually about 12% with a
light floral aroma becoming very refined and delicate with age. It has less
intensity of colour and lighter structure than the other varieties and also
takes about five years to show its intrisic qualities. On the palate, it is
floral with a finish of average length and fruitiness. When grown in a hot
place the aroma is much spicier, but not as pleasant when young, or as fine
when old.
Touriga Francesa
Despite the name Francesa, this is strictly a Douro grape, with no connection
to any known French variety. It is mentioned with this name for first time
only in 1940.
Although of high quality and interest, it is of less intrinsic fineness than
some of the other top varieties. Colour is good and reasonably lasting, but
not so much so as Nacional, Roriz and Barroca.
Touriga Francesa is maturing early with average-sized clusters, and productivity
is higher than Touriga Nacional and Tinto Cão, but lower than Tinta
Roriz and Barroca.
Although adaptable to different soils, it needs warm growing conditions to
attain the alcoholic strength necessary for Port: It reaches about 12% alcohol,
has an excellent pH balance of 3.45, and is rich in phenols.
The aroma is the most floral of the varieties, with rose predominating. In
good years rockrose is also in evidence. Less aggressive than Roriz but more
robust than Barroca, fruit and tannin are wellbalanced but not of great quality.
Despite a long, intense finish, it has a rather earthy taste.
Nonetheless, an excellent blending variety because of its structure and floral
aromatic components.
White varieties
Malvasia Fina
This is clearly the most common white grape, used for most of the white Ports.
However, it is often also mixed with small volumes of one of the other three
white grapes. Malvasia Fina is also increasingly seen in table wines from
the Douro.
Viosinho, Donselinho, Gouveio
These grapes are often used as the second grape in the white Port blends as
"second violin" to Malvasia Fina.
Harvest
Harvesting the grapes is a daunting task in the Douro valley: the grapes are
picked entirely by hand, in vineyards that slope at an average of 45º,
at a time of year when the sunshine reflecting off the schisty soil pushes
the temperature up to 40º C.
Fortifying the wine
After two or three days of fermentation, during which the sugar turns into
alcohol, it is time for the delicate process of adding measures of grape spirit
to halt the fermentation. The grape spirit is 77% strong alcohol distilled
from grapes and virtually tasteless and aromaless. Without this spirit Port
would still be what it was in the past: a coarse, dry red wine with an alcohol
content of 12-13º. The addition of grape spirit releases the wine's flavour,
without however disturbing its balance. After this process is complete, the
wine rises to 19-20º in alcoholic strength.
The process that happens when the strong grape spirit is added is as follows. Most yeast will cease all activity at alcohol levels above 14%. This means that when the alcohol is added, the yeast dies, and as it has not yet transformed all the grape sugar into alcohol, there is a residual level of sugar in the wine, giving Port its usually sweet taste. The addition of the stronger spirit gives Port wine its alcohol content of 19-20%. (By law the level of the finished product must be between 19% and 22%).
At Rozès, we are currently doing experiments in viticulture, producing grapes with a higher level of sugar from the beginning. This means that the yeast can transform more sugar into alcohol before the desired sweetness is reached and the fermentation is stopped. Following, the amount of grape spirit that needs to be added to reach 20% is smaller, and we get a wine with more taste and aroma (less tasteless liquid).
Storing in Douro
It then spends the winter resting in the "quintas" before setting
off on the journey to Vila Nova de Gaia.
Transport to Vila Nova de Gaia
In days gone by, the young wine was carried by boat: large barrels called
pipes (550 litres) were loaded into "barcos rabelos", flat-bottomed
vessels with square sails.
This perilous journey over the tumultuous waters of the Douro was necessary to allow the wine to mature peacefully in the more humid surroundings of Gaia. Upon arrival, the wines are checked by the experts of the Port Wine Institute.
Today, all transport is done by trucks from Douro to Vila Nova de Gaia, and the only time of the year is at the annual Rabelo boat regatta, where the boat owning Port wine houses compete in a friendly match of sailing.
Maturation in the cellars
The barrels are then stored by vineyard and vintage in the dim vaults of the
cellars at Gaia, for 3 years, 5 years, 10 years, 20 years, 40 years or longer.
It is the cellar-master who decides. The ageing potential is not something
decided once. Over the times, the cellar master and his team of oenologes
taste and test the wine to see how well the wines develop inside the casks.
Port wine is almost like a child nurtured by its parent (the oenologe), i.e.
the wine can make troubles in its infancy, but eventually they all grow up
to become fantastic wines.
The oak casks used for the matuaration also have influence on how the wine develops. Contrary to the production of table wines, we always use used oak casks for the maturation of Port wine. This is because, Port wine must by law be stored in oak for at least three years, hence there is no hurry to draw the tannins out of the wood as it is the case with table wines that usually spend six months in oak. Also, the primary purpose of the casks in the production of Port wine is to allow small amounts of oxygen to penetrate the wood and oxidize the wine. The wooden aromas and tastes are secondary to this, as the wines already have a high level of tannins.
There is also difference in which type of oak is used to build the casks. At Rozès we solely use French oak previously used to make some of the finest Hennessy Cognacs. The advantage of French oak is that the pores in the wood are very small, hence the oxidation process is slower, and the end result more delicate and refined.
Two other types of oak can also be used to mature the Port wine: American oak and Portuguese oak. Basically, American oak has pores somewhat larger than French oak, speeding up the maturation process. Portuguse oak has by far the largest pores of the three types of oak. Because of the porosity of Portuguese oak, the oxidation process is faster but also cruder, hence it should only be used for low quality wines, that do not need the careful oxidation offered by French oak.
Blending
The cellar-master is also responsible for the delicate task of blending. For
like Champagne, Port is not a wine transferred directly from vat to bottle,
but the product of careful blending, patiently created by mixing at least
fifteen different wines of varying ages and qualities. The cellar-master will
choose a young wine for its liveliness and fruit, an older wine for body,
another for smoothness or bouquet, until the blend has all the characteristics
typical of the style of each Port house. In outstanding years vintages are
made by blending wines from a single year.
Once the blending process is complete, the Port is left to mature once again, to become rounder, smoother, mellower. Like all great wines. The average ageing period is a minimum of three years, the longest ever demanded of a wine. However, the ageing method varies according to the type of wine that is being made.
Bottling
The bottling of the Port wine has different implications to different styles
of Port. The Vintage types are bottled after two years of maturation in oak
casks, and these wines continue to develop in the bottle. Therefore, such
wines are usually bottled and moved to another part of the cellar to continue
its development there.
On the other hand, Ports of the Tawny style (including 10 years old, 20 years old, etc.), will end their development once they are bottled. Therefore, they are sold right after the bottling. It also means that there is no point in keeping Tawny Ports in private cellars in the hope of maturing them further. They will not improve.
Commercialisation
Having begun its history as something produced and drunk in Portugal for many
centuries, discovered by the British, today, genuine Port wine from Portugal
is sold in over 100 countries around the world. Most of the volume is still
sold in Europe with France, Netherlands, and Belgium as the largest export
markets.
However, in countries outside Europe, Port wine is gaining popularity like no other alcoholic beverage. In North America it is especially the Vintage Ports that face great popularity whereas the Asians tend to enjoy the aged Tawnies.