Did you know that oak barrels tend to be the second biggest expense for a winery, after the cost of the grapes? Oak barrels from France are the most expensive, with the price being US$1000 and up. Less expensive barrels from the USA go for between US$300 – $500 a barrel. Eastern Europe also makes oak barrels, at a price between the USA and France barrel prices.
In France, there are several different forests where the oak trees are harvested: Allier, Limousin, Nevers, Trancais and Vosges. It has been said that barrels produced in France have less influence on the flavours of a wine, compared to American barrels. This is due in part to the tighter grain of French oak compared to American oak. There is also the differences in barrel production.
In France, the coopers let the wood air dry for 24 months, while in the United States the wood is kiln dried in a shorter time period. The French coopers split the wood along the grain of the wood to make the staves, while in the United States the staves are produced by sawing the wood. It has been determined that splitting the staves causes the wood to impart less flavour in the wine. Some American coopers are now using the traditional French approach to cooperage and producing more subtle barrels.
Some of the flavour from the barrels comes from “toasting” the barrels. A winemaker can order a Light, Medium, or Heavy toast for a barrel. The decision regarding amount of charring is made based on the grape variety used and the style of wine desired.
For less expensive wines, buying new French or American oak barrels is out of the question. So what can a winemaker do? During the fermention, the winemaker can add oak chips, or have oak staves in the tank. This gives a big whack of oak flavour, but doesn’t integrate as nicely as barrel aging.
Also barrel aging allows a slow interaction between the wine and air from the outside, softening the wine. So through a one year period, a barrel will lose a few bottles of wine to evaporation. This lost amount is called the “Angels share”. Every few months the winemaker will top up his/her barrel with wine to prevent too much air in the barrel. That’s all for now on oak barrels. Something to think about when you open a bottle of oaked California chardonnay. Enjoy!