To understand the flavours of the various wines you taste, you have to understand the flavour of oak in wine and the reason oaking exists.
The first thing to know about wine is that oak barrels do not grow in vineyards and that the flavour is not intrinsic to the natural flavour of wine.
The flavour of oak is introduced by contact with barrels used for storage and/or transport made from that wood. Sometimes, actually, quite often, the oak flavours overpower the other wine flavours, in which case it is considered to be “overoaked”. Barrels made of new oak contribute a very strong flavour to wine. In fact, up until the 1980s no French wine grower worth his salt would ever, ever have put good wine into barrels made of new oak!
In red wines, the oak flavour components include “vanillin” or vanilla, and so-called “toasty”, “charred” or “roasted” or “caramelised” elements. In white wines, the flavour component is generally “buttery”. Vanillin and butter comes from the character of the hardwood. The three others derive from the “charring” of the barrel that occurs from the flaming of the interior of the barrel to be able to bend the staves into place.
The second thing to know is that the reason oak barrels came into existence was mainly for the transport of wines and the storage of wines.
To understand how this came about, I shall take you back in time to the Roman period when Julius Caesar invaded Gaul (as France was then known) in AD 52.
As the Roman army invaded deeper into Gaul and went more northwards towards the Benelux countries and onwards to England and Scotland (where they stopped) two things became apparent:
- That they needed large amounts of wine for the Roman army, and
- That there were not enough vineyards in Gaul. (There were only a few small vine regions planted by the Greeks around the Mediterranean basin.)
This was a bit of a worry as wine was particularly revered by the Romans for its digestive and medicinal qualities, its ability to disinfect food, as well as being very pleasant to drink! Pliny the Elder wrote a lot about wine. Unfortunately, the names of the varietals he mentioned are not known today.
The Romans set about importing wine from the best vineyards in the world, the slopes just outside Pompeii, and the Etruscan vineyards.
Initially, the transport was by boat. They loaded wine-filled amphorae onto boats and then onto donkeys on arrival. As they travelled into the hinterlands of Gaul, much of the wine was lost. This was mainly due to the amphorae falling off the donkeys and breaking; also due to the native Gaulois (pronounced gol-wah) who loved wine so much, they couldn’t get enough of it. They would hijack the caravans whenever they could.
By the end of the 2nd century the boats were constructed in such a way that they were like floating tanks. The inner tanks which held the wine were made of clay and sealed with molten lead. The wine was then transferred into large wooden containers of up to as much as 1200 litres or into animal skins or bladders and transported up river.
The Romans noticed that the Gaulois used barrels made of yew wood for the transport and storage of their ales. They started to use this for wines but it was not a success. In AD 70 Pliny denounced the “deadly effects of these strange recipients of yew wood made in Gaul”.
It is thought to be soon afterwards that the first oak barrels would have carried wine.
When Vesuvius erupted in AD 79 it wiped out all the vineyards surrounding Pompeii. It was from this date that the Legions planted vineyards in France in earnest, starting with the Rhone Valley, Aquitaine, the South-West, and Bordeaux regions, moving north towards the Loire Valley. There is evidence that the vineyards of Sancerre and some parts of Muscadet date from the Roman occupation. Also a stone grape-press dating back to the 2nd century was found just south of Tours indicating that the Touraine vineyards could date back to that period.
When Eleanor of Aquitaine became Queen of England in 1153, after having tasted the local English wines she set up the commerce and transport of her own favourite wines from the South West of France though the port of Bordeaux.
The containers used for this transport were, of course, oak barrels.
Later on in the Middle Ages the Dukes of Burgundy set up a transportation network of their wines to the Benelux countries, again, in oak barrels.
In the areas up and down the Loire Valley, the wine grower only had to take their wines 4 or 5 kilometres up the road to the local château or castle. He would transport his wines in oak barrels or vats, tip them out into storage tanks, and always brought the oak barrels back home again. In the Touraine region, excavations beneath the Château of Chaumont found wine tanks dating back to the Middle Ages hewn into the Tufa rock face and lined with glass tiles.
Today, it is still traditional to age the wines in glass; we use bottles.
First published June 2008