The Role Of Barrels In Winemaking

How do barrels influence wine? This question may have popped into your mind as you swirled and sipped wine amongst the views of wine country. There are a lot of options and factors that make barrel decisions complex for the winemaker. It is an important decision as the chosen vessel will direct the structure and flavor profile of the wine. It ultimately reflects the winemaker's style, but can also elevate a grape variety. From toasts to wood preferences, the barrel options vary greatly and can make a wine go from good to outstanding. Barrels are the backbone of wine. Let's take a moment to appreciate the humble wood vessel.

Quick Overview of Barrels
Barrels can be used for $50 planters and chairs, but they start as an expensive vessel for aging alcohol like wine. The journey to complete a barrel is long, spanning many years to craft.

Oak barrels are sourced from various forests. In California, the most commonly sourced oak barrels are from the United States and France. The best-growing conditions for oak trees are cold to mid temperatures with poor soil of sand and limestone. These conditions help create regular annual growth for the oaks and lend tighter rings in the trunk. Nutrient-rich soil encourages quick growth and focuses on leaf development. The slow time is crucial in forming tight grains in the wood. Harvest time for these oaks is not until the trees are 80-250 years old.  For extra-fine grains, the optimum harvest time is 150-230 years old.

After all those years, the oak wood must be seasoned and dried post-harvest. This process can take 2-3 years. After the seasoning process, the oak is finally delivered to a cooperage for barrel crafting. A craft that dates back to the Roman era. The cooper takes separate pieces of oak wood (staves) to shape the barrel, which is held by riveted rings (hoops). To encourage interaction with the wine's flavor, the cooper chars the inside of the barrel. The toast level is based on the charring temperature and duration. One could try to be a wordsmith and describe the entire process in more detail, but it is best to see the skill in action:

    Journalist Jamie Goode's video of Tonnellerie

    Business Insider's video on Large Format Barrels

Once barrels are completed, cooperages offer various woods, grains, toasts, and sizes to winemakers. To the untrained person, the list of options is daunting but to the experienced winemaker, it is an exciting opportunity to further the artistic vision of their wine. How does the winemaker decide what barrel to use? Let's take a step into the winemaker's boots.

Varietal Differences
Wine varietals influence the initial barrel selections. A white varietal like Chardonnay will have different needs from a red varietal like Zinfandel. Yet red varietals will vary in needs from each other as each varietal has its characteristics. A Grenache is lighter in body with tart red fruit notes whereas a Cabernet Sauvignon will have more weight and dark purple/blue fruit notes. A wine's origin, terroir, and vintage will also impact the different needs for structure, body, and flavor.

Style
A winemaker will have a goal and idea of what they want for their wines. They desire certain flavors, structures, and wine bodies, which barrels can help deliver. Some winemakers seek tradition, while other winemakers desire to break norms to create something new and different. Each winemaker has a different goal.

Oak barrels incorporate secondary notes in the wine. There are three types of flavors or notes in wine:

• Primary - The variety's characteristics and vintage influence (ie: weather). The primary tastes are fruits, vegetal, herbs, and florals.
• Secondary - These are the notes that come from winemaking practices and vessel choices such as oak barrels. The secondary notes are typically coconut, butter, toast, vanilla, cedar, coffee, and spices.  
• Tertiary - These notes derive from aging. These will develop and are forward in aged wines. These tertiary tastes reflect the aging process and are usually dried fruits, mushrooms, nuts, spices, sherry notes, and earthiness.

Oak and aging can impact the flavors dramatically in wines, which is why it is up to the winemaker to make the decision on how oak will play a part in their program.

Wood and Grain Choice
One of the important decisions a winemaker has to decide is the wood and grain choice. A common choice for winemakers in Paso Robles is American vs. French oak.

American oak can be less dense with looser wood grains, which means the oak can be sawed as opposed to hand-splitting. This means oak sourced from the United States is a little less expensive. The oak can be sourced from Pennsylvania, Virginia, Missouri, and Minnesota. Each forest lends different qualities to the oak due to soil and weather.

French oak has tighter grains with rich aromatic compounds which help create structure, smoothness, and longer aging capabilities for wines. There are various French oaks that help with complexity and volume. The oak in France is generally hand-split, which raises the cost of using French barrels.

This is just a quick overview of American and French oaks, but there is a plethora of choices for winemakers including different cooperages. Winemakers generally taste samples of wine aged in different barrels and discuss with cooperages their barrel characteristics to make informed decisions. It also can be a trial and error as winemakers will refine their barrel choices over the years of winemaking. At Parrish, we use 4-5 different cooperages from several different forests in France. This assists in the complexity of our wines.

Toast
Oak wood barrels go through a toasting process. The toasting helps flavor compounds such as coconut, spices, butterscotch, and vanilla be more prominent in the barrels. Natural, raw oak is stable and offers roundness for wine, but the vanillin and furanic compounds deliver more complexity that winemakers seek.

In the winery at Parrish, we use Medium+ level. Winemaker Cody Alt shares, "Medium+ offers softer wood tannins, which helps not add to the already existing tannins in our wines. Our wines have enough concentrated flavors that they can handle higher toast levels in the barrels. The oak adds complexity with notes of roasted almonds, coffee, toffee, and mocha."

Roll Out the Barrels
There are still so many factors to oak barrels, but our main goal was to give you a glimpse into the world of oak and build appreciation for the art of coopers (as well as winemakers). Oak barrels are an integral part of winemaking and are widely used for their complexity and structure abilities in wine.

A fun exercise for your next wine tasting. While enjoying your next glass of wine, see if you can pick out the secondary notes which are the oak influence.