What are the best trees for wine barrels? Find out in this article.
Wine barrels assist in the aging process of wine and whiskey.
In early winemaking, the amphora was the vessel of choice for the storage and transportation of wine.
Due to the perishable nature of wood materials, it’s difficult to trace the usage of barrels.
The Greek historian Herodotus, noted that ancient Mesopotamians used barrels made of palm trees to transport the wine for long distances along the Euphrates.
Palm is a difficult material to bend and fashion into barrels, however, wine merchants from different regions, experimented with different wood styles to find a better wood source.
One of the best trees for wine barrels is the Oak tree. The use of oak has been prevalent in winemaking for at least two millennia, first coming into the widespread use during the time of the Roman Empire.
With time, winemakers discovered that, beyond just the storage convenience, the wine kept in the oak barrels took on properties that improved it, by making it softer and, improved the taste.
Throughout history, other trees including chestnut, pine redwood, and black locust have been used in crafting winemaking barrels or vessels which included large fermentation vats.
However, none of these wood types possess the compatibility with wine that oak has demonstrated.
In combining its watertight yet slightly porous, storage capabilities with the unique flavor and texture characteristics that it can impart to the wine it is in contact with.
Apple and Cherry wood
Other hardwoods like apple and cherry wood have an off-putting stench. Australian winemakers have a history of using black locust barrels.
Historically, chestnut was used by Beaujolais Italian and Portuguese winemakers.
Some Rhone winemakers still use paraffin coated chestnut barrels but coating minimizes any effect from the wood, making its function similar to the neutral concrete vessel.
In Chile, there are traditions for using barrels made of Rauli wood, but it is beginning to fall out of favor, due to the musky scent it imparts on the wine.
Types of trees used to make wine barrels
Of all the varieties of trees available, the Oaktree has emerged to be the greatest in wine and barrel making at large.
Three of the oak tree species have been selected out, as those that are best suited for wine storage and aging.
These are French oak, Hungarian or European oak, and American oak respectively.
Let’s explore each of the trees
1. French oak
In France, both the Quercus robur and Quercus petraea are considered apt for winemaking.
However, the latter is considered far superior for its finer grain and richer contribution of aromatic components like vanillin and its derivates, methyl-octa lactone, and tannins as well as phenols and volatile aldehydes. French oak typically comes from one or more primary forests: Nevers, Troncais, and the Vosges.
The wood from each of these forests has slightly different characteristics.
2. Hungarian oak
Before the Russian revolution, Quercus petraea oak from Hungary, was the most highly sought-after wood for winemaking.
The trees in the Hungarian Zemplen Mountains grow more slowly and smaller in the volcanic soil creating fine tight grain which sequentially lends itself to a very delicate extraction.
3. American oak
The species of oak that is typically used for American oak production is the Quercus alba which is a white oak species and is characterized by its relatively fast growth, wider grains, and lower wood tannin.
It’s found in most of the Eastern United States as well as Missouri, Minnesota, and Wisconsin. while many wine barrels are from Oregon Quercus garryana, white oak has started to gain usage due to its closer similarities to European oak.
The American white oak is particularly popular because of the flavoring it adds to both wine and whiskey. It has been used for thousands of years to age wine.
There are many reasons for this which include, the fact that it contains garlic acid which is a pseudo form of tannin or a pseudo tannin.
This adds a good deal of spice to anything aged within its confines.
Grapes tend to respond very well to this type of atmosphere and it works well in enhancing flavor.
From trees to barrels
- Designing the perfect barrel is a very long process that usually begins with the selection of the best tree, the long, straight trees that are 80-120 years age are selected and marked for felling. This gives space for other smaller trees to grow.
- The branches and top part of the tree are cut off, to minimize any damages like cracking or breaking the trunk. For French oak, the wood is slated along the grains due to its less watertight nature, a lot of wastage is therefore incurred as only around two barrels can be made from an oak tree. The American counterpart is more watertight and slates can be sawn out, due to the presence of gum-like substances and tylones that plug the pores making the barrels watertight.
- The staves are then seasoned out or dried under the weather, this allows for natural drying to take place. Weather elements like rain and sun add the required flavors and reduce the number of tannins in the staves. Oak is let to dry in the open for about 18-22 months with regular turning to ensure even seasoning. Large dryers can also be used to quickly dry the staves indoors; however, it does not provide barrels that are suitable for long time wine aging.
- The cooper then selects the best fitting staves that can fit into a circle, they are shaped and polished. Coopers use either water or fire to make them pliable and fit them into a circle.
- A series of iron bands are then used to join the rose petals into a cylinder, giving the barrel its shape.
- The barrels are then toasted with fire to the desired toast level, either light, medium or high toast. The toast levels of the barrel can bring out varying degrees of mocha and toffee notes in red wines. The staves are then shaped and planed and lids placed. The barrel is then thoroughly checked for leaks and the cooper’s logo and wine name imprinted. The barrels are ready for wine filling and are transported to the cellar.
Cost of barrels
The cost of barrels varies due to the supply and demand and can change with different features that a cooperage may offer.
As of late 2007, the price for a standard American oak barrel was US$600 TO $800, French oak $1200 and up, and Eastern European $600.
French oak is more expensive because only a few barrels can be formed from one tree, it also takes longer to mature and is limited in supply.
The French oak is nonetheless preferred by coopers due to its small fine grains.
The American oak has wider grains but is more available and takes around 60 years to reach maturity. Hungarian oak is the cheapest of the oaks.
Due to the expense of barrels, several techniques have been devised to save money.
One is to shave the inside of used barrels and insert new thin inner staves that have been toasted.
Effect of oak on wine
Due to its porous nature, the oak barrel allows evaporation and oxygenation to occur in wine but typically, not to levels that would cause oxidation and spoilage.
The typical 54 gallons or 225-liter barrel can lose anywhere between 5.5 and 6.5 gallons which are about 21 to 25 liters of mostly alcohol and water in a year through evaporation.
This, in turn, allows the wine to concentrate its flavor and aroma compounds.
Small amounts of oxygen are allowed to pass through the barrel to act as a softening agent upon the wine’s tannin.
The chemical properties of oak can have a profound effect on the wine. Phenols within the wood interact to produce vanilla type flavors and can give the impression of tea notes or sweetness.
The degree of toast on the barrel can also impart different properties that affect the tannin levels as well as the aggressive wood flavors.
The hydrolyzable tannins present in the wood, known as ellagitannins, are derived from lignin structures in the wood.
They help protect the wine from oxidation and reduction.
Wines can be barrel fermented in oak or placed in oak after fermentation for a period of aging or maturation.
The wine matured in oak wood receives more oak flavors and properties than wine fermented in oak because yeast cells present in fermentation interact with and latch on to oak components.
When dead yeast cells are removed as lees, some oak properties go with them.
Characteristics of white wine fermented in oak
A pale color and extra silky texture. White wines fermented in steel and matured in oak will have darker coloring due to heavy phenolic compounds present.
Flavor notes commonly used to describe wines exposed to oak include caramel, cream, smoke, spice, and vanilla.
Chardonnay is a varietal with very distinct flavor profiles when fermented in oak which includes coconut, cinnamon, and clove notes.
The length of time a wine spends in the barrel is dependent on the varietal and finished style the winemaker desires.
The majority of oak flavoring is imparted in the first few months the wine is in contact with the oak, while longer-term exposure adds light barrel aeration which helps precipitate phenolic compounds and quickens the aging process.
New world Pinot Noir may spend less than a year in oak.
Premium Cabernet Sauvignon may spend two years. The very tannic Nebbiol0 grape may spend four or more years in oak.
High-end Rioja producers will sometimes age their wines up to ten years in American oak to get a desired earthy cedar and herbal character.
Differences between American and French oak
- American oak tends to be more intensely flavored than French oak with more sweet and vanilla overtones. American oak has two to four times as many lactones. Winemakers choose American oak typically for bold powerful reds, base wines for assemblage or warm climate Chardonnays.
- Besides being derived from different species, a major difference between American and French oak comes from the preparation of the wood. The tighter grain and less watertight nature of French oak come from the preparation of the wood. The tighter grain and less watertight nature of French oak oblige coopers to split the wood along the grain. The wood is then aged or seasoned for 24 to 36 months in the open air in a so-called wood yard. Since French oaks must be split, only 20%-25% of the tree can be utilized. American oak may be serrated which makes it at least twice as economical. Its more pronounced oxidation and a quicker release of aromas help wines to lose their astringency and harshness more quickly, which makes this the tree of choice for shorter maturations which could be six to ten months.
- Because of Americas’ oak modest tannin contribution, the perfect first fill is a wine with abundant tannins and texture as it allows the fruit to interact harmoniously with the wood which contributes a wide array of complex aroma and soft yet very palatable tannins.
- French oak, on the other hand, generates silky and transparent tannins which transmit a sensation of light sweetness combined with fruity flavors that persist in the mouth. Spices and toasted almonds are noteworthy, combined with flavors of ripe red fruit in red wines and notes of peach, exotic fruits and floral aromas like jasmine and rose in whites this all depends on the grape variety.
Barrel wine aging is popular and produces the best flavor desired in both short term and long-term stored wine.
With time, the action of wine on the barrel, walls will reduce the ability of barrels to impact the required tannins and phenyl compounds in wines.
Old barrels can be scrubbed to expose new surfaces though the taste will never be the same.
Also considering that only the inside of the barrel is in contact with the wine winemakers today have started to use oak chips and flakes.
This can alleviate the pressure on the current tree reserves on the conservative side but barrels remain the heart of wine making.