What Is Cognac?

We recently published an overview of brandy, and while it hopefully gave a good understanding of the breadth and depth of different spirits available around the world it was a bit light on details. There’s a good reason — brandy can get a bit complicated. Today’s specific variety is the case in point. So join us as we dive deeper than you probably ever wanted to go into the world of French cognac.


Humans have been producing wine for longer than the entire span of recorded history. The first indications of what we could recognize as the production of wine date from 6000 BCE in Georgia, and the technology and process for creating the delicious liquid spread throughout the ancient world. France is one of those countries that has been blessed with an amazing climate that makes it perfect for the production of wine, and as the Greek and Roman empires expanded into the region they brought with them the knowledge of winemaking that firmly took root in the area and continues to this day.

Wine is great. It is a delicious, complex beverage that (when manufactured and stored properly) is a joy to drink. But wine can be finnicky — stored for too long, or at the wrong temperature, and it degrades into vinegar. Basically unless everything lines up perfectly, from the production to the transport and storage, what comes out of the bottle at your table might be worthless.

In a world before refrigeration and rapid transport, faulty wine was an unfortunate fact of life. Sometime around the 15th century, Dutch traders introduced the process of distillation to the French wine makers and immediately some of them latched onto this process as a way to make their otherwise annoyingly temperamental bottles of wine into a shelf stable and temperature insensitive product that could be shipped around the world. Originally, this process was used to create fortified wine but, as the process was improved and perfected over the centuries, eventually some producers stopped trying to use the distilled alcohol to make the wine better and instead started using wine to try and make the distilled spirit better.

Raw Materials

Cognac originally started as a way to preserve wine for longer periods of time, but over the years it has drifted and adapted. It is still required to be made from 100% grape juice, but the specific variety of grape has changed considerable.

Rather than using some of the more common wine making grapes like merlot or grenache the majority of grapes used for the production of cognac are ugni blanc, a variety of white grape that is far sweeter than most other kinds of grapes but also comes with additional unpleasant bitterness. That makes it undesirable for normal wine production, but when making a cognac the extra sugar means a higher alcohol yield and the bitter taste can be either removed during distillation or improved during maturation.

Grapes for cognac production are grown in the regions surrounding the city of Cognac in the southwestern area of France, just a bit down the coast from La Rochelle. The most commonly discussed regions are identified as:

  • Grande Champagne
  • Petite Champagne
  • Borderies
  • Fins Bois
  • Bons Bois
  • Bois Ordinaires

Grapes are grown on independent wineries and vineyards in these regions, and once they are appropriately ripened they are picked, crushed, and pressed to extract the sugary juice from within the grapes. Interestingly, the French government specifically forbids the use of mechanical presses during this process as it has a tendency to introduce undesirable flavors into the wine.

One other thing to note for those wine enthusiasts out there is that the use of sulfur dioxide is forbidden in the production of cognac. Grapes have a tendency to degrade and decompose quickly once picked, and as a result some wineries use sulfur dioxide gas pumped into their storage facilities to preserve their grapes before they can be pressed or shipped. Sulfur is a particularly difficult component to remove during distillation and can have a massive impact on the flavor of the distilled spirit, so the use of this kind of preservative is not allowed. Which means that vineyards will try to minimize the time between when the grapes are picked and when they move into fermentation.



The massive breakthrough that humans had with wine was when they realized that the process of fermentation was a good thing. The alcohol created during this process not only made early humans more attractive and popular at 6,000 BCE discos, but it also made the liquid more sanitary and allowed it to last longer. Fermentation happens when yeast cells start eating sugar, releasing alcohol as a byproduct of their digestive process.

Grape juice is “easy mode” for creating a fermented beverage, since the naturally occurring sugar in the grape juice will readily and spontaneously ferment if given the opportunity. Most wineries will use cultured yeast cells, varieties of the microorganisms that have been specifically selected and grown to produce prodigious quantities of alcohol and also just the right flavors that are desired in the final product.

After fermentation, the liquid has somewhere between 7% and 12% alcohol by volume. It’s a little lower than the alcohol content for a typical wine, but that allows additional flavors to be cultivated and distilled later on in the process.

Something else that happens at this stage is a process called “malolactic fermentation”. Although it isn’t a legal requirement, it is something that is pretty much universally done within the industry. During this process the malic acid in the wine (which is naturally occurring within the grapes) is eaten by a second strain of bacteria and converted into lactic acid. The end result is a less acidic and tart wine, and also one that has a much more hostile environment for any other bacteria that might come along later to spoil the wine. Which, since the use of preservatives like sulfur dioxide are prohibited, is necessary to preserve the wine until it can be distilled.



Up until this point, things are pretty standard in terms of winemaking in France. There are some peculiarities, but it basically feels like any other winemaking process. But this is where the gardening stops and the science starts. And as you might expect, there are just as many rules about this part of the process as anything else.

It all starts with the timing. Cognac follows what’s called a “compte” system, where the aging process is strictly monitored and controlled, and each distillation season must be complete on or before March 31st each year. This has the interesting effect of encouraging a larger number of independent vineyards to have their own distillation facilities, since there’s a much shorter window between November and March to perform the distillation and having the facilities on-site means you aren’t at the mercy of anyone else’s schedule. It also allows the same workers to be employed year-round, tending to the vineyard in the spring and then distilling during the winter.

Still design is also tightly controlled, requiring the use of traditional processes and materials and a more hands-on approach. This example of a traditional cognac still actually resides in upstate New York at Tuthilltown Spirits and is used for their experimental runs.

All cognac stills are a single pot design, meaning that the cognac is distilled in batches slowly over a longer period of time. The pot still (on the left, embedded in the brickwork) is directly heated with open flames, a more temperamental method than the modern steam jacket approach and likely to scorch and ruin the wine unless extreme care and attention is paid at all times. Pot size is restricted with cognac production, with the smaller volume requiring more distillation runs and closer attention paid to each one compared to larger Scottish operations.

Once the wine reaches the proper temperature the vapors from the wine rise and travel through the swan’s neck at the top of the still and enter a worm tub condenser, pictured on the right. This contraption has a coil of copper tubing inside, and a continuous stream of cold water surrounds that tubing encouraging the vapor to condense and turn back into a liquid.

The more astute of you may have noticed a strange onion shaped vessel in the middle of the frame here, connected to both the pot still and the condenser. This is an optional portion of the still design called a “wine heater” which does what it says on the tin — it holds an additional charge of wine and allows it to pre-heat before being added to the pot. Since the size of the pot is restricted in cognac production, this enables the distiller to maximize their time by having essentially a second distillation run already queued up and ready to go which minimizes wasted time between runs. The vessel is heated by having a line of copper tubing connecting the top of the still with the top of the worm tub condenser, acting both as an initial condenser for the heated vapor and also simultaneously heating the next batch of wine.

Cognac is created using two distillation runs, a premiere chauffe and a bonne chauffe in French and roughly analogous to a “stripping run” and “spirits run” in Scottish parlance.

For the first distillation run, distillers closely monitor the liquid coming out of the still and selectively capture the components they want for their finished product. The early and late portions of the run (the tetes and queues or heads and tails) are captured and re-used in the next batch, but that middle fraction referred to as the brouillis that the distillers have carefully selected are moved on to the second distillation run. What’s left in the pot at the end of the distillation is referred to as vinasse and is discarded.

For the second distillation run the brouillis is added to a second still and the process repeats, but with one added step that instead of just capturing three components (tetes, brouillis, queues) this time they make one extra cut. The heads and tails are still captured and re-used all the way back in the first distillation of the next batch, but the brouillis is further divided into the coeur or heart and the secondes which is almost as good, but just needs some more time. Those secondes are added to the next batch of brouillis going for their second distillation run.

Confused? Yeah, me too. This one is a little complex. But the general idea here is that there are two distillation runs for the spirit, where the cognac-to-be is carefully teased out of the wine and skillfully monitored by the distillers.

One final twist to the process, a choice that distillers have to make, is whether to remove the dead yeast cells. Referred to as “lees”, these cells make the wine a bit cloudy and are typically strained out of the mixture before distillation. But some distillers leave them in — the direct open flame heating means that the lees can be cooked in the wine, and that Maillard reaction and esterification can impact the style of the spirit.

However it happens, the finished spirit or eau-de-vie (water of life) must not exceed 72.4% ABV. The reason for this relatively low maximum alcohol content is to ensure that the flavors and aromas that make cognac unique and interesting are preserved — if the alcohol content gets too high, then those components will be stripped out of the finished product.



All newly distilled eau-de-vie must be matured for a minimum of two years before it can legally be sold as cognac. This process is measured starting April 1st each year, the first day after the distillation must be completed.

Generally speaking, most cognac is first barreled in new French oak barrels. This fresh oak allows the spirit to soak up the maximum level of delicious oak-y flavors while it is still young.

As the spirit matures it is continuously tasted, and similar barrels of spirit are combined into what are referred to as coupes and managed as a group. Some spirits are moved into progressively older barrels as they mature, reducing the impact of the oak flavor and enabling a longer maturation window. Other barrels are decanted into “inert” vessels like glass, which stop the maturation process and preserve whatever flavor the spirit has attained.

Blending and Post Processing

For pretty much every glass of cognac you’ve ever had, it is likely to be a blend of different vineyards and distillers that have all been brought together to form the perfect flavor profile according to that manufacturer’s specifications. Very few manufacturers have a single source of spirit for their bottles.

At some point during the maturation process, the spirits from these different sources are brought together and begin to be blended together. This happens well in advance of the bottling process, often years in advance, allowing the spirit time to properly blend and “marry” in the barrel before it is bottled. This is starkly different from the American practice of directly blending different barrels at the time of bottling.

Prior to bottling, there are a couple of different additives that can be used to change the flavor, the appearance, or the sugar content of the cognac.

  • Syrup Barrels are one traditional method of increasing the sugar content. Oak barrels are filled with fresh pressed grape juice, allowed to sit for a while to soak it up, and then emptied and re-filled with new spirit. That spirit absorbs some of the sugar content from the wood as it matures and is then blended with other barrels to pass along that sugary component.
  • Faibles are weaker barrels of spirit that have been proofed down below 30% ABV on purpose, allowing for the blender to slowly reduce the alcohol content or make other changes to the blend.
  • Boise is a substance that is created by breaking down old oak barrels and boiling the staves. This creates a brown colored liquid with tons of sweetness and rancio flavors that can be added to a blend of cognac.

All of these methods create additives that can be blended into the cognac prior to bottling.

For cognac, if a region appears on the bottle it means that 100% of the grapes used for that bottle came from the specified region. The only exemption is with the “Fine Champagne” designation, where 100% of the grapes need to come from the Champagne regions around Cognac, but at least 50% needs to come from the Grande Champagne region specifically.


Age Definitions

For cognac, there are about five levels of age statements that can be added to the bottle. As with other spirits this denotes the youngest drop of cognac in the blend, but can include much older components as well. And interestingly, this all hinges on an April 1st date for each tranche of spirits rather than the actual date that they entered the barrel.

And, even more confusingly, for a couple of these (like the two year mark) there are multiple phrases that all basically mean the same thing.

2VS, Very Special, Trois Etoiles
4VSOP, Reserve
10XO, Hors d’Age


There’s a very good reason why cognac is so complicated: it’s delicious. This is one of those spirits where people have recognized that something delicious and unique is going on here, and as a result people have collectively decided to take proactive steps to protect that uniqueness. It also helps keep all of the workers and businesses running thanks to that protection, ensuring that we will have delicious cognac to enjoy for decades to come.


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