Wood essences used in cooperage2 September 2021
While the use of oak (Quercus robur, Quercus petraea and Quercus alba) dominates today very largely the cooperage, it has not always been so. Different archaeological studies have indeed shown that the barrels were originally made of softwood. Oak has established itself over the centuries, first for mechanical issues, then more recently for its organoleptic qualities which have made it the preferred container for maturing the finest wines and spirits.
The study by Élise Marlière * has made it possible to date fairly precisely the period from which the use of oak supplants the use of conifers in the manufacture of barrels. The archaeologist was able to identify the species constituting 131 barrels of his study: 78% are coniferous, mainly fir (58%), 13% in a mixture of fir-spruce or fir-larch and 20% in deciduous trees of which 19 , 8% oak.
The use of fir is predominant in the manufacture of barrels from the 1st century BC to the end of the 1st century AD. Which of oak does not increase significantly until the 2nd century AD to permanently replace the fir tree in the 3rd century AD. Several later archaeological discoveries confirm Élise Marlière’s study of the use of conifers in the manufacture of antique barrels. The barrel 268 of Donau-Ries in Munningen (Germany), dating from the 2nd century AD, consists of 22 fir staves and 12 hazel hoops. Ditto for the barrel discovered in Troyes and made up of 19 spruce and fir staves from the 1st century AD **, for that of Kastell Celeusum in Pförring (Germany) made up of 25 fir staves, as well as that of Aislingen (Germany) consisting of 22 coniferous staves from the 2nd century AD and Silchester (England) in silver fir dating from the 40s-70s AD.
Oak gradually established itself from the 3rd century AD because of its many properties such as its ability to resist bending, its narrow and regular rings, its impermeability, its microporosity and its aromas released by heating (toasting ). Even if all these properties were not yet known in the 18th century, Fougeroux de Bondaroy already noted in L’Art du tonnelier (1763) “that we usually chose oak wood, to make stave and bolster, because that a tight wood is needed, and which does not rot easily. “The author nevertheless specifies that chestnut and beech could be used and that in southern countries the” mulberry tree is used by coopers to form barrels or parts to transport wine, and especially to the construction of small barrels, seals, seilles, etc. ”
Of all the oak species recorded, only the sessile oak (Quercus petraea), the pedunculate oak (Quercus robur) and the American white oak (Quercus alba), from France, Eastern Europe and the United States. United States of America are now used in cooperage. If oak has proven its worth, the fact remains that cooperage professionals are constantly looking for improvements, particularly with regard to the selection of woods, drying methods or even the intensity of the drying. heating in order to respond more precisely to the expectations of the wineries.
* Élise Marlière, The barrel in Roman Gaul, 2001.
Visuals © Christophe Deschanel