A little vocabulary
And first of all, what is balsamic vinegar? Unlike wine vinegar, which is obtained by fermenting wine, balsamic vinegar(aceto balsamico) is obtained by fermenting cooked grape must.
The term "balsamic" derives from the Italian balsamo, balsam, and is used for the first time in the early eighteenth century to describe a vinegar with healing properties (the use of vinegar was not only culinary). From the 19th century onwards, the term "balsamic" was systematically applied to vinegar made from cooked grape must.
It is also important to distinguish the balsamic vinegar of Modena PGI (Protected Geographical Indication) from the traditional balsamic vinegar of Modena DOP (Denominazione di Origine Controllata). Both are produced in a defined geographical area, that of the ancient territories of the Este family, which today corresponds to the province of Modena and partly to that of Reggio Emilia. Balsamic PGI, the most widely marketed, is made from cooked grape must (minimum 20%) with wine vinegar (minimum 10%) and sometimes caramel. The traditional DOP balsamic, much more prestigious, is made from a single ingredient: cooked grape must. It is aged for at least 12 years and is marketed in bottles of 12 or 25 years of age.
Finally, the vinegar producer is called the vinegar maker(acetaio) and the place of production is the vinegar factory(acetaia). The vinegar factory is located in the attic, an environment subject to the strong summer heat, which favors the fermentation process, and to the rigorous winter cold, which interrupts the evolution of the liquid: it rests and acquires its clear and brilliant aspect. Unlike wine, therefore, balsamic vinegar needs significant temperature variations.
A centuries-old tradition
The practice of cooking grape must seems to date back to the Romans: sapum, so called by the Roman poet Virgil, was appreciated both in cooking and for its medicinal properties. Since the 11th century, vinegar produced "in the Modena way" has enjoyed a good reputation, but it was the Este family, head of the Duchy of Modena from the 13th century, who helped to make it known among the European courts. An anecdote is enough to illustrate its prestige: in 1792, on the occasion of the coronation of Francis I of Austria at the head of the Holy Roman Empire, Duke Hercules III of Este donated a bottle of balsamic vinegar, no less!
Within the Modenese families, it is a solidly anchored tradition transmitted from generation to generation, the fruit of a patient know-how. The gestures are passed on in the attics of the houses, and the last bottle drawn is jealously locked up by the mistress of the house and reserved for special occasions.
Since 1967, a consortium, the Consorteria dell'Aceto Balsamico tradizionale, controls the production of the traditional balsamic vinegar of Modena. It is an association of passionate volunteers responsible for the preservation and dissemination of traditions related to balsamic and its production (consorteria-abtm.it). More recently, the Consorzio Tutela Aceto Balsamico di Modena has been working to obtain a PGI in the 1990s, and is working on a regulation that guarantees the quality and authenticity of balsamic against imitations circulating on the market (consorziobalsamico.it).
The production of the traditional balsamic vinegar of Modena
Three elements are necessary to obtain the precious condiment: cooked grape must, a battery of barrels and finally a lot of patience and attention. Only locally grown grape varieties are allowed (trebbiano, lambrusco, etc.). After the harvest, the grapes are crushed and the must obtained is cooked in copper or stainless steel cauldrons for several hours until the juice has reduced by about two-thirds; the impurities that rise to the surface are gradually skimmed off during the cooking process. The grape juice obtained is concentrated and has a beautiful amber color. It is poured into glass or stainless steel tanks where it rests until spring. It is then in a battery of wooden barrels that the magic happens. A battery is made up of at least five barrels of decreasing size and of different and exclusively local wood species: oak, chestnut, juniper, mulberry, cherry, etc. Each type of wood gives the wine its own tannins and enriches its aroma.
In these containers the alcoholic fermentation takes place: under the effect of yeasts, part of the sugars is transformed into alcohol. Then the acetic fermentation takes place: in contact with oxygen and at a certain temperature, the alcohol is transformed into acetic acid. The fermentation process takes place in the largest barrels of the battery; those of smaller dimensions are reserved for maturing, during which the flavors and aromas are developed, and for aging, through which it acquires nobility and roundness.
The successive passages in the barrels follow precise rules: the first year, the new barrels are filled with cooked grape must. The first year, the new barrels are filled with the cooked grape must and, since they have an opening on their upper side, the contact with the ambient air causes the evaporation of part of the liquid. After a year, a quantity of product is taken from each barrel to be transferred to the next largest barrel. The first barrel receives the grape must of the new year. These same gestures are perpetuated each year and in the twelfth year, a small quantity of balsamic vinegar, one or two liters, is taken from the smallest barrel and bottled. This is called traditional balsamic vinegar affinato. It is necessary to wait twelve years to obtain the first bottle of the precious elixir! From the twenty-fifth year, the vinegar is defined extravecchio. Its aromas have become rounder, its sweet and sour flavor is balanced and it has acquired an inky opacity.
Some tips to discover the traditional balsamic vinegar
The Museo del Balsamico tradizionale di Spilamberto is an excellent introduction to the world of balsamic (museodelbalsamicotradizionale.org).
Several producers organize guided tours (free or at a very low cost), followed by a tasting of their products; this is the case of Villa San Donnino (villasandonnino.it), the Leonardi farm (acetaialeonardi.it) and Venturini Baldini (venturinibaldini.it).
In Modena, the tourist office (visitmodena.it) and the Modenatur agency (modenatur.it) have a complete list of the acetaie that are open to the public and can make reservations for you.
Aware of the heritage value of balsamic, several cities have recently established an acetaia comunale (municipal vinegar factory) and organize guided tours to be booked through the tourist offices: this is the case of Vignola, the first acetaia comunale founded in 1998, and Modena.
