I recently did a story on corks and how they were the unsung heroes of wine. Perhaps barrels also should be considered in the same vein or as a winemaker’s secret ingredient. See the story on corks can be found at: The Cork – The Unsung Hero of Wine « California Wines & Wineries (californiawinesandwineries.com) .
Wine aficionados are always talking about barrels and how the barrel has imparted this or that flavor. So what exactly happens when wine is stored in a barrel? Where does the wood from the barrels come from? How did barrels become a defacto method of aging wine? What does toasting do for the barrels and subsequently the wine? Hopefully these and other questions will be answered in the following story.
History of the Wine Barrel
The oak barrel dates back to the Greek historian Herodotus and people transporting barrels from ancient Mesopotamian along the Euphrates River (350 BC). In Roman times it was a convenient and durable way to transport wine. Oak barrels have historically been used in both the fermentation process as well as the aging process of wine. Using oak barrels allows more integration of the wine during fermentation.
Anatomy of a Wine Barrel
(Picture from Social Vignerons)
Types of Wood for Barrels
Key reason to use oak is while the cooper/cooperage makes the barrels “leak proof”, oak allows oxygen in very small amounts to impart a change to the wine over time. For example, barrels can make a wine smoother and less astringent.
The two primary types of oak used are French oak and American oak. That said, oak barrels also come from Hungary, Romanian and Slavonian French oak are known for more subtle aromatics and adding nutty and smoky flavors. American oak, with larger pores, provide a faster impact on the wine and provide hints of vanilla and coconut. Some winemakers even chose to mix the two traditional oaks by aging a portion in one type and a portion in another before combining for bottling. Other winemakers may choose to use an American oak but use a French oak head. This provides for a smoother finish and enough oxygen to form the right amount of tannins to help in for color retention. Other woods are also available such as Cherry wood which imparts a dark red fruit flavor and aromatics of toast with a softness and sweetness. For example a winemaker may use 20 barrels of oak and one barrel of cherry.
When a barrel is new, it will influence the wine to a much greater degree. When a barrel has been used two or three times, it is considered “neutral” but will still allow the wine to age, preserving the fruit flavors. Most winemakers when choosing the barrel profile to go with a specific varietal of wine, will use a combination of new and used (neutral) barrels to lock in a winemakers intended desire.
Barrel sizes are not standardized but many use a 225 liter barrel which produces 25 cases of wine. These barrels can range in pricing for American oak of approximately $500 to $1,000 for French oak.
Recently I interviewed a very well know winemaker whose supplier uses optical sorting to select both tight grain and wide grain staves, then pieces the barrel together using the staves alternating tight and wide grain. This allows for a slow and even aging process in the same barrel.
Toasting of Wine Barrels
(photograph from TN Coopers )
Traditionally barrels are toasted using an open flame in the middle of an open barrel. That said more recently, other methodologies are available like convection toasting which is more replicable, repeatable and consistent. Other ways also include radiant heat and longer convection toasting of oak. Different toasting and methodologies provide different aromatics such as sweeter aromatics, caramel, vanilla and spice characteristics. With each of these methods, different levels of roasting are available to the winemaker. Toasting is considered one of the key contributors in giving wine a “mouth feel”. Generally winemakers’ order their barrels “light, medium or heavily toasted” to get the correct flavor profile for the type of wine going into the vessel.
Most of the discussion of oak barrels revolves around red wine, however one of the exceptions is oaked California Chardonnay. The barrels selected are instrumental in creating buttery (along with secondary malolactic fermentation), crackerjack and popcorn flavors.
Other options for to get “oak” in the flavor profile can come from imparting an “open mesh cloth with pieces of oak” in a barrel or stainless steel tank. Sometimes this is known as chips, blocks or staves being used.
The selection and characteristics of choosing a barrel is a “science” unto itself for most winemakers as discussed in this brief story. This is why on most winemakers’ notes it is stated that X% was new French or American oak and Y% was “neutral or 2 year old oak barrels”. Perhaps your next sip of a strong red wine, you can taste and differentiate the oak barrels used and how they affected the wine?
On a personal note I would like to thank Mary Beth Suther at TN Coppers for her time spent with me and her “barrel knowledge”.