Traditionally, port wines and red wines in the Douro region are vinified in so-called "lagares”. A lagare is a container made of granite, usually with dimensions of about 4 x 4 m with a depth of about 1 m. The grapes (with or without stems) are poured into this container after the daily harvest. Once the harvest workers return from the vineyard, they first enjoy a fortifying supper and then put on short pants, wash their feet and climb into the lagare to tread the grapes for approximately five hours, squashing the grapes in this process while mixing the juice with the skins and achieving the best possible leaching.
In general, a lagare contains between 10 and 15 "pipes" (of 550 l each), i.e. between 5,500 and 8,250 liters. As a rule of thumb, it takes one to two people per pipe to carefully tread the grapes. Consequently, there are approximately 20 people in a lagare when the so-called "Corte" begins. This is the first treading stage: the workers stand in one (or more) rows, place their arms on their neighbors' shoulders and march forward or backward step by step, following commands (frequently accompanied by drumbeats or rhythmic song). The Corte is usually complete after two or three hours and is followed by the so-called Liberdade, in which workers move freely and often dance.
Once the grapes have been squeezed the volume begins to heat up, since the wild yeast from the skins comes into contact with the natural sugar from the grape juice. This is when fermentation sets in. In this process more and more color is extracted from the skins of the berries. After five hours of careful treading, the workers leave the lagare. A snack is usually served at midnight and then everybody gets some well-earned rest before the harvest work in the vineyard is resumed the next morning.
Meanwhile, the skin, the stems and seeds rise in the lagare and form the "cap", which always has to be re-submerged to allow for further leaching.
After 24 to 36 hours of fermentation a large portion of the sugar has fermented. If the production is intended for port wine, an enologist conducts continuous tests until the desired residual sugar content has been attained. At this stage, the juice is separated from the solid parts and 77% brandy is added (about one fifth). The alcohol eliminates the remaining yeasts, fermentation comes to a halt, and the young port wine is filled into casks for maturation.
In the case of red wine, the fermentation continues until it comes to a natural halt (dry).
Since it is becoming increasingly difficult to find workers for treading grapes, "automatic lagares" have been introduced in the Douro region over the past years. Frequently, the quality of the result cannot be distinguished from foot-treaded wines.
While lagares continue to have major significance for the vinification of port wine, most red wines (and also all white wines) in the Douro region are vinified with the classical method. The first part of the maceration is partly still done in lagares, but fermentation for the most part now takes place in large wooden or stainless steel containers and the maturation in barriques.
