Slow aging in barrels matures wine
The magic of wine barrels
It's easy to imagine how cultivating grapes and making wine taught humans many things. Horticulture most certainly. Fermentation technology--today is used in everything from bread to water purification--is another.
But perhaps most important was barrel-making. Humans needed a vessel to move this precious new trade good with wide popularity. Someone fashioned a crude wooden cylinder that a single man could roll around, at the same time creating a vessel that's used now for everything from petroleum to nails. It all started, arguably, with the humble wine grape, vitis vinifera.
Today the oak barrel--that's the 225-litre version the French call "barrique"--is still at the heart of the wine-making process. And the men who make the barrels, called "coopers," are the last of the original artisans working with ancient materials and processes who still produce--by hand--objects that have not changed appreciably for centuries.
Why are oak barrels still used today despite the end of their days as shipping vessels? Because somewhere along the way winemakers discovered wine barrels weren't just good for shipping wines. They found out that when they stored wine in oak barrels a couple of good things happened.
First, aging wine in oak barrels helped mature the flavours of the wine by slowly allowing minute exposure to air. Too much oxygen can kill a wine, by "oxidizing" the flavour of the wine, leaving it tasting of sherry or port, not a good thing in still table wines. But very controlled exposure can ripen green flavours in red wine. (For the most part white wines are not subject to barrel aging, being even more subject to oxidization than red wines.) Also, because water actually evapourates out through the barrel staves and around the barrel cork, or "bung," barrel-aging actually concentrates the flavour of the wine. The water that evapourates is referred to as the "angel's share." (When I head into the Barrel Room with my wine thief, my wife accuses me of trying to beat the angels to their share.
Second, oak gave off pleasant flavours, that when combined with red wine, had a very pleasing effect on the flavours and aromas of the wine, especially if the oak was toasted. Today, exposure to newly toasted oak wood gives the wine lovely aromatics of vanilla and coffee, with flavours as disparate as chocolate and butterscotch. Along with the rich red fruit of the wine grape, these new flavours build the complexly-layered flavour profile of a hand-made red wine.
Today's winemakers have a lot more options for giving wines the oak flavour profile. Oak dust is added during primary fermentation, oak chips while the wine is going through secondary fermentation, and oak staves right in the stainless steel tank to emulate oak barrel aging. And even that slow exposure to oxygen that barrels provide can be reproduced mechanically with a process called "micro-oxygenation," in which minute quantities of oxygen are slowly bubbled through the wine.
But there is nothing like oak barrels to build a richly-layered wine. At the winery we often note how a batch of wine, split into barrels, all tastes the same when it comes out of the press, but after two or three years, each barrel ends up tasting very different from the others. As you taste the barrels (did I mention we do a lot of "tasting" at the winery?) month after month they diverge in flavour. As they near time for bottling, we assemble a sample from each barrel, taste and make notes about the flavour profile of each, then start experimenting with blends of different proportions of each barrel. This is where the fun begins. By the end of the day, our teeth are red from tasting each different blend, but we have a recipe for what we hope will be another awesome Syrah, cobbled together with parts of up to a dozen different barrels. We can hardly wait for the actual blending when we get the final tank sample that gives us the first real glimpse of what the final wine will taste like.
After that the barrels, if the wine that was in them was clean, are refilled and go back into our barrel room to work their magic on a new vintage.
For my money, there's nothing that places me most firmly in a winery than staring down a long row of barrels full of wine with my wine thief in my hand, intent on beating the angels to their share. I think I hear my barrels calling me now. See ya!
Cheers!
Keith
Keith Watt is owner and winemaker at Morning Bay Vineyard & Estate Winery on Pender Island, BC.
The Magic of Barrels