The Mighty Oak – the history of wine barrels
The first wooden barrels weren’t used for wine. They were invented by the Celts of central Europe more than 2000 years ago and used mainly for beer. The Romans picked up the idea as a more robust alternative to their traditional clay amphorae. Initially, it was the sturdiness and portability of barrels that appealed. But, over the centuries, European wine-makers realised that something magical happened to wine stored in oak barrels.
Oak has a tight grain, which helps keep the barrel watertight. But tiny amounts oxygen can seep through the wood, softening the wine and providing the right environment for malolactic fermentation. Compounds from the wood add to the complexity of the wine, including flavours of vanilla, caramel, coconut and spice.
A fiery craft
The barrel maker, known as a cooper, first prepares the long pieces of oak known as staves. These are seasoned outdoors, often for several years. The barrels are shaped by softening the staves with fire or steam and applying pressure from metal hoops. Once the barrel is constructed, the inside is ‘toasted’ over a flame. The degree of toasting or ‘char’ affects the character of the wine, with a heavier char releasing more vanilla, toffee and caramel flavours and a lighter char allowing the oaky tannins to predominate.
French or American?
Wine barrels are generally made from French oak or American Oak, although some wines (typically at the lower end) may use oak barrels from Hungary or Russia. Higher-end wines generally employ French Oak as it has a finer grain and imparts more subtle flavours. American oak may be the wine-maker’s choice for a bolder red such as a cabernet sauvignon or a shiraz. Back in the 1970s, these big oaky wines were all the go but these days the trend is to towards more elegant styles that let the fruit shine through.
Old or new?
A wine barrel has a limited lifespan. And with a single new barrel costing around $2000, it’s one of the most significant expenses for the wine maker. New barrels will impart the most flavour to the wine, but after three or four uses will contribute very little. The choice of new oak, older oak, no oak or a combination depends on the grape variety and the aims of the wine-maker.
While maturing the wine in a barrel is the traditional way to obtain the oak characteristics, there are shortcuts. Toasted or untoasted oak chips or staves can be added, either during fermentation or as the wine matures. The chips also can be used in combination with used barrels, boosting the intensity of the flavour compounds. Because flavours from the chips are extracted more quickly, they are only kept in contact with the wine for a relatively short time
Big or small?
The smaller the barrel, the greater contact the wine will have with the wood. The standard barrel used in Bordeaux is the barrique, which holds 225 litres. However, with today’s trend away from heavily oaked wines, more wine makers are using older, bigger barrels. Giant barrels, called foudres, hold thousands of litres of wine. Big vats and foudres were often used in the early days of Australian wine making and are enjoying a comeback. You’ll find quite a range of complex whites, and even sparkling, aged in a foudre, but the method is also used for some reds. Many wines are never exposed to oak. With stainless steel or plastic containers, it’s the character of the fruit that defines the resulting wine.
Barrels with a kick
Whisky is commonly aged in barrels previously used for wine. But in 2014, Jacob’s Creek launched two red wines finished in whisky barrels – their Double Barrel range. They say the Double Barrel Shiraz benefits from the more assertive notes of Scotch whisky, while the Cabernet Sauvignon suits the smoother style of Irish whiskey. Wine, plus wood, plus whisky. It’s yet another twist on the magic of the barrel.