Oh the Difference a Barrel Makes
By Diego Meraviglia
Barrels have served a fundamental purpose in the production of fine wine for centuries, but it wasn’t always this way. If we rewind the clock back to the time of the ancient Greeks and Romans, who are recognized as the commercial pioneers of winemaking, the use of wood as a raw material for the creation of wine-containing vessels was completely absent. Indeed, clay amphorae were used instead. These containers did not impart any flavor to the wine but merely acted as neutral containers with the single exception that the large porosity of clay would allow the wines to receive oxygen, a factor that would hastily age the wines, sometimes excessively, creating intense aromas of oxidation that can be defined as “nuttiness”, at times so strong that the personality of the wine could be considered compromised.
We can think of wines like Sherry, Madeira and Marsala as examples where this is purposely sought. It was not until the Romans began their territorial expansion, specifically under Julius Caesar in 50-60 B.C., that the Romans came into contact with the Gauls, a Celtic people residing in what is today Northern Italy. They were first presented with the notion of wood as a raw material for the production of wine-containing vessels.
Strabo (63 B.C. – 24 A.D.), a Greek geographer and historian, described the Gauls people in Northern Italy as, “Tall, prosperous, capable of producing great wine that they preserve in great wooden barrels the size of houses.” The ready availability of wood as the primary raw material, coupled with their historically famous thirst, generated the construction of larger wooden containers for housing and transporting wine. Little could they imagine that this would have changed the face of wine forever and become second nature in wine production 2,000 years later.
Barrel Specs and Effects
So what exactly does wood do to wine? What are the specifics of the barrels and do they carry different effects on the wine? Do wines aged in stainless steel carry the same characteristics and what are the most common wines that are aged in barrels?
Every wine produced in the world undergoes a minimum amount of aging time. This time is essential for the stabilization of the recently fermented grape juice that requires less or more time, depending on the type of wine we are aiming to produce, in order to round itself out, become more palatable and gather the desired aromatic complexity indicative of its price point and style. Every winery makes a choice on what raw material they wish to age their wine in and for how long.
Stainless steel vessels are present today in almost every winery. They are industrially produced vats that carry with them the benefits of easy cleaning and sanitation, easy temperature control for the fermentation process, as well as the housing of wine for periods of time. Unlike wood, they are not limited in their lifespan. But most importantly, stainless steel does (or doesn’t do…) two specific things: impart flavors or allow oxygen contact. In other words, stainless steel will not alter the aromatic profile of a wine, nor will it allow the wine to oxygenate, hence developing its flavors into what the wine world defines as “tertiary” (aromas related to oxidation/aging that can be referred to as nuttiness, earthy, musky, ethereal and so on…aromas that are not simply fruits, flowers and minerals).
It is hence evident that all wines aged in stainless steel alone will not develop into more complex, deeper aromas and will normally be wines that are fruity, floral, mineral and youthfully fresh. Examples of these are the majority of Pinot Grigio or any “unoaked” wine. They can be both white or red, although pure stainless steel aging for reds is less uncommon. The focus here is to preserve and enhance the freshness, the herbaceous, grassy, young and lighter body profile of wines that will arrive on the shelf with lower price tags and will generally be less age worthy and cellar prone than their counterparts aged in wood.
The moment we decide as winemakers to produce wines of full body, aging capabilities, complexity, depth and by consequence an elevated price tag, wood becomes mandatory. For the vast majority of reds, a minimum amount of time in wood is essential. Reds possess fuller structure to begin with and require more softening than whites per norm. Wood behaves far different than stainless steel. Not only will it allow minimum amounts of oxygen into the wine through its porous structure, but more significantly it will actually impart flavor to the wine through the physical release of aromatic substances in the wood that dissipate and dissolve into the wine.
Aging Time Span
Upon making the determination that we wish to age our wines in barrels, be it as low as three months to as long as four to five years, we need to make a series of choices that will define the specific influence of the barrels on the wine:
• What type of wood?
• What origin?
• What size barrels?
• What age or “neutrality” of barrels?
• What intensity of charring/toasting?
• How much percentage of the wine will go through each variant?
The combinations can truly be endless and they are studied and cherished by all wineries like secret recipes.
Type of Wood
First of all, we must determine what type/species of wood we will utilize. Through the centuries and thanks to the Bordeaux wineries in France, oak has largely been determined as the best type of wood for wine barrels. Oak is intensely flavored but delicate in its profile, with luscious sweet tones of vanilla, dill, cedar, tobacco and cinnamon, at times even coconut. It has a small tight grain, which means it allows only small amounts of oxygen to enter, micro oxygenating the wine and allowing it to soften through the small but not excessive exposure to air. Oak is indeed prime. It is, however, not impossible to find other wood types, less common but more prevalent in Europe, such as cherry, elm, chestnut, each with a set of aromas and characteristics, generally harsher and less elegant than those of the more expensive oak that can cost up to $700 per single small-sized barrel.
Secondly, comes the origin of the wood. French? Slavonian? American? Russian? These four origins are recognized as the primary producers of wood for barrel manufacture and each carry with them specific traits.
(left to right): Oak Tree in France; Slavonian Oak Tree; 450 year-old Russian Oak Tree; American Oak Tree in New Orleans
French is the most expensive with the sweetest aromatics, vanilla being the most recognizable and is the one largely preferred by fine wineries. Slavonian is extremely common in Italy and has a less impactful character, a more savory quality rather than sweet with aromatics of walnut, hazelnut and nutmeg. American is by far the most powerful and impactful. Used largely for spirits like Bourbon, that same “Bourbon” aroma can be detected in the wine. Large doses of coconut, dill, eucalyptus and more balsamic-like notes will be imparted.
A favorite of countries like Spain and Australia, American oak can, at times, overpower any other flavor in the wine. Russian is the new kid on the block for oak wooden barrels, and is still under scrutiny, although good neutral results have been achieved.
Beyond the flavor component, each wood and provenance will possess different sized grain, depending on the speed at which the trees grew, and that will determine how much oxygen the barrel will actually allow into the wine during the time it rests.
Barrel Size Matters
Beyond the provenance of the wood, we will then need to decide on the size of the barrels. It may seam irrelevant and simply logistical (the bigger the barrels, the more wine we make) but in reality, the size of the barrels is fundamental in how intensely “oaked” the wines will be.
The concept is quite straightforward. The smaller the barrel, the larger the surface area to wine contact ratio and the more intense effect the wood will have on the wine. The larger the barrel, the less impactful the wood will be and the more neutral the wine will remain. Indeed, many wineries opt to age their wines in combinations of small and large barrels that can come in dozens of sizes all the way up to large Italian “botti” that contain 10 to 60 hectoliters of wine – far more than the American or French favorite called “barrique,” with its 225 liter capacity.
Age & Use
Unexpectedly, the “age” of the barrels, or “use” of the barrels, is also an important decision wineries need to make. A newer, younger barrel will impart more flavor than an older barrel. It is widely accepted that for smaller barrels, the like of the common French barrique, three years is the general maximum. Three years are equivalent to three uses, three vintages. With each use, each vintage, each year, the barrel loses some of its potency. Beyond three years, most barrels are considered “neutral”, at which point the only use they have is to micro oxygenate the wine and soften it from this air exposure, but will not impart any active flavors or aromas.
Large barrels commonly used in Italy are considered the epitome of “neutral” wood containers, used exclusively for their oxygenating properties but not for any flavor addition.
Last but not least, the most spectacular-in-production aspect of barrels is the charring. Each barrel produced by coopers will be toasted to a specific degree, defined as light, medium or high toast. The coopers literally burn blocks of peat inside the newly made barrels to char/burn the inside.
The duration of this charring will increase the burn, which in turn will provide different flavors to the wine. Light toast barrels will provide notes of hazelnut, milk chocolate, vanilla and macadamia. Medium toast, the most common, will increase the smoky character and darken the chocolate component ever so slightly. High toast barrels are less commonly used as they impart strong smoke flavors, dark cacao, coffee.
So what are the wines that will carry these characteristics? What wines fit under the “barrel-aged” category? Largely speaking, the majority of red wines see some sort of barrel at one point in their production phase and it is an absolute given that any fine red wine with a more than entry level price tag and any sort of aging capability will be largely determined by its barrel regimen.
In Italy we see wines the like of Barolo, Barbaresco, Amarone, Chianti, Super Tuscans, Taurasi. In Spain Rioja, Navarra, Priorat and Ribera del Duero are largely characterized by their cooperage. France has a traditional and historical love affair with barrels, and America is completely dependent on wood vessels for its wine production, having developed a compassion for the profile that barrel-aged wines possess. Australia comes also heavy handed on the use of wood barrels for its wines.
The Whites, Not So Much
White wines are also aged in barrels, although less commonly. It was the French region of Burgundy that largely established the trend of barrel use in white wines, with their native Chardonnay grape. The world followed their footsteps and Chardonnay, although just a grape varietal that can be widely found unoaked, is subjected almost always to some degree of barrel aging. Bigger structured, fuller body white wines are the main ones to carry some sort of wood aging, although the vast majority of white wines are stainless-steel aged to preserve their approachable, fresh and youthful character. Any grape and any place can barrel age their white wines, so it would be a common error to say all Chardonnays are oaked and all Pinot Grigios are not. Asking and inquiring on the barrel regimen becomes essential with white wine. Is this white wine oaked?
As we can see, the intricacies and details involved in the selection of barrels are extremely complex and the study of cooperage in wine is something that is ongoing and continuously evolving as we discover new methods, new concepts and new raw materials. Ultimately though, they have intensely shaped the profile of wines we enjoy today and have become a natural byword of winemaking throughout the entire globe, standing testimony to how unexpectedly pioneering were the actions of a few Celtic tribes stationed in Cisalpine Gaul in Northern Italy and Transalpine Gaul in France over 2,000 years ago.