It’s become such a familiar sight as we wander around vast cellars on a wine tour – the huge wooden casks lying on their sides while their precious description ages inside. But have you ever stopped to wonder why wooden casks were used in the first place, and why a modern alternative hasn’t stepped in to replace them?
The History of the Wooden Cask
Like many things, the wooden cask was born out of necessity. The Romans were expanding their empire and they wanted to take their favourite grape-based drink along with them (not only because they enjoyed imbibing, but also because in the event of contaminated water sources, the Roman soldiers could drink wine instead).
But transporting their favourite tipple around the Roman Empire was a tricky business. The Greeks and the early Romans had relied on clay storage containers called amphorae, but as the Romans traded and travelled further afield there was an increased problem with breakages in the brittle clay, which meant much of the precious liquid transported was wasted.
The Mesopotamians, at this time, were already using wooden barrels made from palms but palm wood was difficult to get and hard to work with. It was not until the Romans travelled north and encountered the Gauls that a solution presented itself.
The Gauls were already using oak barrels to transport beer and oak was readily available across the Roman Empire. The wood’s close grain meant that leaks were less of an issue, and it was easy to bend with only a little heating.
The Romans began to transport their wine in these oak barrels and made a fascinating discovery: the oak barrels actually added a distinct flavour to their descriptions. As they carried these barrels further and further distances, they discovered that the longer the wine remained in the barrels, the more the oak flavour – created by the heating the wood underwent to bend it – infused into the beverage.
The idea of aging wine in oak barrels – or casks – was born.
Why Oak?
There’s nothing more awe-inspiring on a wine tour than seeing rows of beautiful oak casks. But oak was never chosen for its beauty. It was chosen originally for practicality and then later because of the subtle depth of flavour it was able to add to the cask’s descriptions.
What the Romans had stumbled upon was the perfect wood to aid the aging process. Thanks to its porous nature, oak allowed just the right amount of oxygenation to take place without allowing oxidation or letting the liquid spoil. This tiny amount of oxygen was just enough to soften the tannins and create a milder, softer drink.
It is no coincidence that today almost all of the world’s best wines are aged using oak casks. It is the properties of the oak, such as the phenols which are released during the aging process, that imbues the liquid with notes of vanilla, spice and cloves. Not to mention the ellagitannins which are released when the wood is toasted to create caramel, charred and smoky aromas.
Of course today there are other alternatives to using expensive oak casks, which can only impart their flavour for a limited number of uses. Many producers now use oak woodchips introduced into vast metal vats to create the same ‘oaky’ flavours. But for me, the joy of seeing row upon row of oak casks on a wine tour is the feeling of connection it creates with a history of wine production which has remained the same for millennia.
Paul Newman is the Marketing and E-Systems Executive for European Waterways, the UK's most respected provider if you're looking for an all-inclusive, luxury wine tour barge holiday in France or other great destinations. Part of a team of experienced barging aficionados, Paul is first in line to endorse the perks of a slow-paced barge cruise to anyone looking for a unique holiday experience.