Wine began stored and aged in amphorae (sealed earthenware or clay jars) that were used in Greece and Rome.
It was the Celts in around 50BD that devised using wooden barrels to store and transport wines (those Celts…so smart!)
Wooden barrels were sturdy and shaped conveniently for transport. And…it seemed that wine could actually benefit from the wood!
Why Oak? Some would say out of convenience and then as a taste preference. There are over 400 species of oak. Only about 20 of them are typically used for wine barrels and these can very with the flavors they impart although most often the flavor noticed is “vanilla”.
In addition to the wood itself you have the toast. Cooperages specialize in specific toasts for the staves and heads of the barrels and the intensity of the toast can definitely affect the flavor of the wine. Toasts are labeled as light, medium or heavy and can very from the barrel staves to the head.
Barrels allow the introduction of oxygen to the wine in a very slow manner. The pace of the introduction depends on the tightness of the grain of the wood. It also imparts the wood flavor into the wine as well as tannins, and body. The body comes mostly from the sugars that are formed when the oak is toasted.
When speaking of types of Oak:
Barrels lose their flavor as they age. Typical barrels can be used for about 5 years before they are done imparting flavor. You get the most flavor extracted on the first use, about 50%. The second use you get about 25% and after that the barrel dwindles toward what is referred to as neutral oak or a barrel that no longer imparts noticeable oak flavor.
So…if after 5 years you have wines to age in neutral oak, you are good! You can keep using those barrels for 100 years or so!
You can increase the life of the barrel and get more use out of it. I have seen photos from the Cilurzo winery in Temecula back in the 60’s shaving down the inside of the barrels to get more exposure to the oak. Shaving at this time was a special art and the people who did it travelled from winery to winery doing this.
This practice picked up in the 80’s and 90’s. Barrels would be shaved and then re-toasted. Shaving costs run about $75 per barrel. A new company out of Australia has a new robot called the Phoenix that uses a high-speed cutting tool to cut 9-10 mm from each stave. This is done by first mapping the interior of the barrel with a laser. Once the interior is cut down the barrels are re-toasted with an infrared machine. I have heard also of adding new thinner staves that have been toasted to neutral barrels.
Now the barrels we are talking about here are the standard 60 gallon barrels that are used in many wineries. The ones you see turned later into planters and lawn furniture. There is a whole different world of barrels out there that are much larger. A great example of these larger wooden barrels can be seen in southern Rhone Style wines where you want less oak contact. Tablas Creek has great (and might I say stunningly beautiful) examples of these.
Barriques are the French term for the typical 60 gallon barrels.
Foudres are 1200 gallon French Oak barrels and hold enough wine to fill 500 twelve-bottle cases.
Puncheons are 120 gallon barrels.
Demi-muids are 160 gallon barrels.
There are also 1600-gallon wooden casks that stand upright, like a fermentation tank.
Foudres, 1200 Galllon French Barrel’s
Other types of containers available
Okay speaking of adding staves…you can use these alternative vessels for aging your wine and still get oak flavor by adding staves and or oak chips.
So that’s the basics of barrels. This is not to be confused with fermentation tanks. That’s a whole ‘nother chapter!