Throughout the world, the oak wine barrel remains one of the most recognizable symbols associated with wine. We have romanticized the barrel and the act of aging wine inside of it to such a degree, that after the barrels have been used for their intended purpose they are often turned into tables, chairs, planters, ice coolers and even barrel stave flags. Surprisingly though, the reason we began aging wine in oak barrels in the first place was not intentional…read on to learn more!
Over two millennia ago, when the Romans began to spread their empire across the globe, they not only wanted to take with them weapons and food, but also wine as it was considered safer to drink than water. It provided calories to malnourished troops, and of course it provided the troops with an intoxicating buzz.
For several thousand years, starting with the ancient Egyptians, clay amphorae (jars with two handles and a narrow neck) were the way armies and traders transported wine over long distances. There were other civilizations, primarily in the Mesopotamian region, who used palm wood barrels, but this was the exception, not the rule. While palm wood barrels weighed far less than clay amphorae, palm wood was quite difficult to bend and shape to the desired shape. Clay offered another advantage in that it was airtight if sealed properly, though this was quite a challenge.
The practice of using amphorae continued in the Greek and then the Roman Empire. As the Romans pushed north into Europe, and away from the Mediterranean, transporting the clay amphorae grew increasingly difficult. This changed however when the Romans encountered the Gauls, in what is today Western Europe, they found a group of people who were using wooden barrels, often made of oak, to transport beer.
The Romans quickly realized they had found a solution to their amphora issue. While other woods were used, oak was popular for a number of reasons. First, the wood was much softer and easier to bend into the traditional barrel shape than palm wood, thus the oak only needed minimal toasting and a barrel could be created much faster. Second, oak was abundant in the forests of continental Europe. And finally, oak, with its tight grain, offered a waterproof storage solution. The transition to wooden barrels was swift. In less than two centuries, tens of millions of amphorae were discarded.
After transporting their wines in barrels, for some time, the Romans and other societies after them, began to realize that the oak barrels imparted new, pleasant qualities to the wine. The contact with the wood made the wine softer and smoother, and with some wines, it also made it better tasting. Due to the minimal toasting of the wood, wines developed additional scents such as cloves, cinnamon, allspice or vanilla, as well as flavors to the palate such as caramel, vanilla or even butter. As the practice of using oak barrels for transport continued, merchants, wine producers, and armies alike, found that the longer the wine remained inside the barrels, the more qualities from the oak would be imparted into the wine, and thus began the practice of aging wine in oak.
Fast forward to today and many wines benefit from coming in contact with oak. Oak can enhance the color of the wine, soften and round out flavors, and impart its own unique characteristics. Almost all red wines and many white wines spend time in oak barrels before being bottled, and that’s just because winemakers have found they taste better that way.
Our own winemaker Terry likes to call his barrels “the spice rack”. Different barrels made in different regions, with different oak varietals and various toast levels all give Terry the “spices” he needs to create the final wines he strives for.
When a wine sits in oak to age, the oak slowly imparts its flavors and colors into the wine. If this is a white wine, the longer the wine sits in oak, the darker a yellow it will become, almost mimicking the hue of straw. If the wine is red, color is not affected as much, but often the longer the wine sits in oak, the darker red it can become.
In terms of flavors, living inside oak is a compound known as vanillin, which as the name suggests, tastes like vanilla. When a wine sits in oak for a long time, that compound leaves the wood and transfers into the wine, which is why many white wines, especially Chardonnay, can have such prominent vanilla flavors.
After a barrel is built, the inside is exposed to fire to “toast” it. This is most commonly done by roasting the inside of the barrel over an open flame of oak mill ends, or by using a hand-held torch. The fire ‘caramelizes’ the wood’s natural sugars and brings out complex compounds. From this, the wine will ultimately take on flavors that are toasty, charred, spicy and sweet depending on the amount of time the wood is toasted.
A lightly toasted barrel spends about 25 minutes exposed to flame while a heavily toasted barrel may get up to one hour of flame exposure.
Essentially, the heavier the toast, the stronger and more varied are the imparted flavors:
Light Toasting – Vanilla, coconut, caramel, clove and cinnamon
Medium Toasting – Vanilla, honey, caramel, toast, coffee, cocoa
Heavy Toasting – Vanilla, espresso, smoke, crème brûlée, butterscotch, toffee, molasses
The heavier the toast the quicker the wine will show the impact of the wood because the heat breaks down the cell walls of the oak and allows it to integrate into the wine faster. A wine aged in a light toast barrel will generally spend at least 18 months to 2 full years in barrel where a heaver toast barrel may only require one year in barrel to get the desired flavors.
The interaction of oak and wine varies depending on the grape variety. Oak may impart hints of chocolate to a Merlot, and vanilla or coconut to a Zinfandel. White wines aged in oak (think Chardonnay) typically develop flavors of vanilla, baked apple, caramel, honey, toasted marshmallow, or buttered toast.
We hope you enjoyed learning a little about wine barrels and we hope to see you at the winery soon.