From grape to glass, nothing symbolises the combination of art and science, nature and nurture, the great outdoors and the cosy confines of the cellar, more strongly than an oak barrel. ‘Trees,’ proclaims even the unromantically encyclopaedic Oxford Companion to Wine, ‘are almost as important to some wines as vines.’
Certainly, wood has been the most popular material for transporting and storing wine for two millennia. It was way back in Roman times that it was found to be a more efficient container than pottery amphorae, and it was only as recently as the mid-20th century that barrels were replaced by glass bottles and tankers for transportation, and joined in the cellar by cement and stainless steel for storage and fermentation.
But somewhere along the line, it was discovered that wood – and oak in particular – actually has a beneficial effect on certain wines – and not merely because it supplements primary fruit flavours with the attractive vanilla, toast, coffee and pencil shaving notes of Quercus robur and sessiliflora (European oaks) or Quercus alba (American). Wood also allows for the very slow oxygenation of wine, which plays a crucial role in softening grape tannins (smoothing the wine’s texture) and naturally stabilising and clarifying it.
Which is why, to this day, barrels are still regarded as the container of choice for fermenting certain white wines and for maturing fine reds – to the point that producers actually seem prepared to spend more money on new wood than fruit.
‘Even if you’re paying as much as R9 000 a ton for grapes, it only works out to about R9 per bottle of wine whereas a new barrel can work out to as much as R30 per bottle,’ calculates Mulderbosch winemaker Adam Mason (ex Klein Constantia), factoring in the time, temperature control and labour involved. ‘The cost of wood is at least equivalent to if not more than the cost of grapes. Sometimes I wonder whether we’ve lost the plot!’
Ataraxia Mountain Vineyards winemaker Kevin Grant reveals that price increases by French coopers and fluctuating exchange rates put South Africans under relentless pressure, while Jordan Winery’s Gary Jordan jokes that where economists use Macdonald’s burgers to work out costs in ‘real’ terms, he uses barrels: ‘We usually work on the basis that a barrel costs the same as a return trip to Europe in economy class. But some years a flight to London is a helluva lot cheaper than a barrel…’
Little wonder, then, that South African producers are increasingly looking at cheaper alternatives to French oak, such as purchasing American, Eastern European and even Chinese barrels, or cutting down on new or first-fill barrels (with second-fill barrels costing 70%, third-fill barrels less than 50% and five-year-old barrels just 10% the price of a new barrel).
Those competing at less-than-luxury levels will also increasingly use oak staves or chips suspended in stainless steel tanks – in fact, Mason is proud to say he had excellent results using ‘planks in tanks’ and micro-oxygenation (bubbling tiny amounts of oxygen through young wine) with Klein Constantia’s second-label KC wines.
At the premium end, though, only the best will do – and because there is no official regulation of the barrel-making business, winemakers such as Mason, Grant and Jordan have to rely on results they have achieved personally rather than the romantic sales spiel of a fifth-generation cooper (let alone the rumours said cooper might spread about his competitors…).
ADAM MASON, MULDERBOSCH (EX KLEIN CONSTANTIA)
The main thing for me is that the wood should never be obvious. It should merely enhance, support and showcase the fruit, and augment the structure of the wine.
When I started at Klein Constantia, we used quite a few coopers which I subsequently whittled down – pardon the pun – to four or five. I use Sylvain for the nice aromatic qualities their wood imparts, Taransaud for enhancing the structure of the wine, Radoux because they’re a good, dependable all-rounder, and every now and again I try someone new for the x-factor. Fortunately I’ve only burnt my fingers once so far…
KEVIN GRANT, ATARAXIA MOUNTAIN VINEYARDS
The most important thing is that wood should never be used as a crutch to prop up the quality of wine. Its use must also be dependent on the winemaker discovering different vineyards’ different personalities. For example, putting Chardonnay with a delicate floral character into a heavily toasted barrel would be a winemaker mistake.
It’s critical to have a good relationship with a handful of coopers, as each puts its own fingerprint even on wood sourced from exactly the same forest. An Alliers barrel from cooper A will not have the same characteristics as an Alliers barrel from cooper B. Sometimes the only thing I specify is a tight-grained wood, because it’s the one thing you can see you’re getting, whereas you can’t ever know for sure about forest or even country of origin.
As far as I can take my coopers’ word for it, I have only ever used French wood
I would also never use a Bordeaux barrel for Chardonnay or Pinot Noir. It’s based on gutfeel rather than hard evidence, but if you think that a cooper in Burgundy drinks Burgundy with his dinner, nine times out of 10, and is constantly comparing his barrels with other locally made barrels, then it makes sense to use Burgundy coopers for Burgundy-style wines.
GARY JORDAN, JORDAN WINERY
A few years ago, we didn’t even get our barrels when the MSC Napoli sank in the English Channel! And our recent lots have gone around the Horn of Africa to avoid pirates – you see, it’s not just about the wood and which cooperage to choose, it’s about the shipping and whether the barrels will arrive in Africa at all!
Each cooper has its own house style. When it comes to toast, for example, Sylvain uses a medium toast which results in coffee and chocolate flavours, whereas a Taransaud barrel with exactly the same spec has a lighter toast and lighter tannins, so a wine would need to spend a long time in it – 12 months plus.
Far too many people use far too much new oak, but more is not better. Even Shiraz benefits from less new oak. A trend these days is to use larger barrels, even though it’s pretty hard to roll a 500l barrel around. But in South Africa we’ve still got lackeys to do it…
THE COOPER’S ART
To make a barrel, you must first plant an oak and wait a century… Then you must use skills passed down from generation to generation over 2000 years, and honed over a lengthy artisanship. Naturally all coopers insist that their oak is the best wood, entirely hand-split as opposed to sawn, and seasoned in the open air, whereas their competitors (they claim) cut corners… But here is a brief summary of how a barrel is made:
- Logs are split into thick slabs, following the direction of the wood’s grain. Ideally, the slabs are then air-dried or weathered (which can take up to five years) or dried more rapidly, using a kiln, before being cut into staves.
- The staves are then assembled to form a barrel, most often around a small fire. The staves are wet so that they bend over the heat, with the fire also ‘toasting’ the inner surface of the barrel (the degree of toast greatly affecting the flavours the barrel will impart to the wine).
- The staves are held in place by iron hoops hammered into place. The ends of the barrel are made of pegged oak, and wedges are inserted to ensure a perfect seal.
WOOD YOU KNOW IT
- France remains the most important country in Europe for oak, with the most significant forests located inVosges,Limousin, Sarthe, Nièvre and Alliers, along with smaller forests in Burgundy, Alsace, the Loire Valley and Champagne.
- Forestof origin is important in that climate affects the density of the grain (the term describing how tightly the fibrous channels in the wood are packed). ‘You might imagine wider-grained woods to be more porous and allow for the transfer of more flavour and oxygen, but in fact this is not the case because they’ve got more polyphenols,’ explains Adam Mason. ‘So finer-grained woods are actually better for aromatic wines like Merlot, while wider-grained woods are better for polymerising more robust, tannic wines (eg Cab).’
- In general North American oak is wide grained, because the reliably warm climate and long summer season results in faster growth (this also explains why South African oak is completely unsuitable). It is richer in tannins and imparts bold, spicy vanillin flavours, hence its traditional use in big, full-bodied red wines such as Rioja and ripe Australian Shiraz.
- Some other woods (chestnut, acacia and cherry, for example) have also played a minor role in wine maturation. ‘I recently discovered some northern Italian winemakers using acacia for their white blends,’ reveals Gary Jordan. ‘For me, it really added something to the wine.’ In South Africa, Bilton has blazed the trail – its opulent, spicy, honeyed Viognier aged in 90% new French oak with a dash of acacia.
[This is the unsubbed version of "A barrel of magic", an article that originally appeared in WINE magazine, slightly updated.]