March 9, 2022

Comparing coffee & alcohol production


For centuries, humankind has worked to perfect the art of producing both coffee and alcohol. We already know that coffee production and winemaking share several techniques (carbonic maceration is a particularly notable example) but where else are there similarities?

From our research, we noted that in particular, there are parallels in production and trade with two major alcoholic beverages: wine and whisky. All three utilise similar concepts and terminology, as well as some crossover with specific techniques.

To learn more about these commonalities, I spoke with two experts from the food and beverage sector. Read on to find out what they told me. 

You might also like our article on coffee liqueurs and spirits.

wine vineyard

Agriculture & production

Terroir is a French word used to describe a set of location-specific environmental conditions that include (but are not limited to) climate, terrain, soil, farming practices, and the effects of local culture and heritage on sensory quality.

Originally coined as a winemaking term several centuries ago, it is now a concept shared between the production of coffee, wine, and to a lesser extent, whisky.

Carlos Andrés Pérez is the head distiller at Altamura Distilleries in Ostuni, Italy. He tells me that there is a debate in the whisky industry around the notion of terroir. 

He says that there are two different concepts of terroir in whisky: the first is defined by the aforementioned environmental conditions, and the second is a broader concept that includes not only climate, soil, and topography, but also cultural heritage and production methods. 

“If we focus on the broader concept of terroir, whisky has it,” says Carlos. “For example, Scotch whisky is made with a set of particular and strict rules, as well as equipment that every Scotch distillery must use.”

For wine, the environmental aspects of terroir are far more significant. Soil properties such as temperature, gradient, and mineral content have a relationship with quality, and local water can further affect sensory profile. This is how wine appellations (a kind of geographical indication) are established.

For instance, cool regions generally produce wines with a higher alcohol by volume (ABV), as the longer development time results in higher sugar content. This sugar then ferments and breaks down to become alcohol. Meanwhile, the opposite is often true for warmer regions, where wines instead have more acidity but lower alcohol levels.

Similarly, when the arabica plant is cultivated at higher altitudes, cooler temperatures extend bean development time. This leads to higher sugar levels, which in turn results in denser, higher quality beans

The target altitude range for the cultivation of arabica coffee is 900 and 2,100 m.a.s.l. These higher elevations are perfect for growing coffee with higher sweetness and acidity. In contrast, robusta is less sweet and acidic, but thrives at lower altitudes.

Temperature and rainfall also influence the flavour of whisky, and have a specific effect on acidity. High temperatures and less rainfall cause lower acidity.

Carlos also explains that the country of origin is important. For a whisky to be Scotch, for example, it must be produced in Scotland. 

Specialty coffee does have some parallels here, but the industry is still working towards the widespread acceptance of geographical indications. 

Some examples do already exist, including the famous Jamaica Blue Mountain Coffee label, as well as the 100% Colombian Coffee indicator. Both of these certifications are protected by national law.

Further down the supply chain, blending is also a common practice for all three beverages. Wine, coffee, and whisky are all blended. In the same way that coffee comes in single origin or single estate lots, there are single malt whiskys (made in a single distillery) and single vineyard wines.

Much like single origin coffee, single malt and single vineyard whiskies and wines are generally agreed to be products which have more individuality, and show more of the vineyard or distillery’s individual efforts throughout production.

wine producers

What about fermentation?

Fermentation is a chemical reaction by which substances are broken down into simpler substances by enzymes. In the case of alcoholic drinks, fermentation is the conversion of sugar into alcohol by enzyme-producing yeasts.

Generally speaking, fermentation is an anaerobic process, meaning that it occurs in the absence of oxygen. Other conditions must also be considered, including the addition of yeast or bacteria, sugar content, temperature, and the use of the right type of container.

Depending on the type of wine being produced, the process can vary slightly. At a fundamental level, white wine is created by fermenting grape juice, while red wine is made using the whole grape, including pulp and skin.

Microorganisms such as yeasts or bacteria can then be added to aid fermentation, converting the sugars into ethanol and other compounds. This gives wine its distinctive aromas and flavours. 

Viva Lenoir is Aromatic Department Manager at Éditions Jean Lenoir, the publishing company responsible for Le Nez du Café, Le Nez du Vin, and Le Nez du Whisky. She says that in the case of whisky, specifically single malt Scotch whisky, malted barley is the crucial ingredient.

The barley is soaked in water for up to a day, allowing the grain to germinate, but not to flourish. This brings out the starch inside the grain. Subsequently, this starch is dried, mixed, and milled, before being soaked in water again. This time, however, yeast is added, allowing fermentation to occur. 

During the drying stage of whisky production, a separate chemical reaction occurs. This is known as the Maillard reaction, in which sugars interact with amino acids, resulting in the brownish colour associated with spirits like whisky. This also creates new volatile flavour and aroma compounds.

The Maillard reaction is also an important aspect of coffee roasting; it gives coffee its sweeter flavours and colour as the sugars within the bean caramelise.

As we know, coffee also undergoes a varying degree of fermentation. Fermentation begins as soon as a cherry is picked, and can subsequently be controlled through processing in a number of ways.

In recent years, experimental processing methods that lean heavily on fermentation have come to be associated with high-scoring specialty coffees. One of the best examples of these is carbonic maceration, first popularised by 2015 World Barista Champion Sasa Sestic. 

The process itself is actually borrowed from winemaking, however. Carbonic maceration involves flushing a tank containing coffee cherries with carbon dioxide, forcing out any residual oxygen and ensuring that the fermentation is entirely anaerobic.

alcohol barrels

How do fermentation vessels vary?

Using the right vessel is more important than you might think. For alcohol in particular, there is a noticeable impact on the final flavour profile.

For example, red wine is usually fermented in oak barrels, resulting in a perceivably smooth flavour. On the other hand, white wine is fermented in stainless steel tanks, which exacerbates its lighter and sharper flavours.

Generally speaking, barrel aging preserves wines and enhances their organoleptic (sensory) properties and chemical composition. It is also said to modify and improve the resulting quality. Furthermore, several chemical reactions are facilitated by the barrel, and the transfer of compounds between wood and wine contributes to complex flavours and aromas. 

When it comes to whisky, barrel aging is key. Viva emphasises that the type of barrel and origin of wood are also important.

“Once fermentation occurs, the whisky is distilled twice to achieve a higher ABV,” she says. “This distillate doesn’t taste like much, of course. Some general types of aromas, such as the peaty ones, can be found, but 80% of whisky’s taste actually comes from the wood.”

In coffee production, the vessels used for fermentation are often simpler. Stainless steel and plastic tanks are common. However, in recent years, experiments with barrel ageing have become more popular.  

whiskey in glasses

What about grading and tasting?

Body, aroma, flavour, and acidity are all attributes that are often used to describe both wine and coffee. Coffee has Q graders and wine has sommeliers, both of which are accepted as professional, accredited tasters. 

Cupping and wine tasting even follow similar scoring processes. This is why there are many similarities between the Wine Aroma Wheel and the Coffee Taster’s Flavour Wheel.

For whisky, however, Viva explains that tasting draws from many sensory wheels. Nonetheless, she says that when it comes to sensory skills, you must make the experience your own.

She says: “You must make it very emotional and personal. That’s the way you are going to find an answer, since it is your cultural background that will allow you to identify some things that you know better than the next person.”

Interestingly, she adds that professional whisky tasters avoid using ice, as the lower temperature affects the molecular composition of the drink. 

This could be equated with the way coffee tasters refrain from adding anything but water to the coffee, allowing it to be evaluated in its purest form.

“Generally, you never put ice in whisky,” she concludes. “However, if it’s something that you like, go ahead. Everybody is entitled to their taste.” 

making pour over coffee

It’s clear that the biggest commonality between these three products is a simple one: their sensory qualities are influenced by their terroir, fermentation, and processing. 

While there might be more similarities than expected, it’s clear that an open dialogue between the wine, whisky, and coffee industries could help to drive innovation across all three in the future. The emergence of carbonic maceration is an excellent example. 

For producers looking to offer increasingly complex and high-scoring coffees, this could be a cue to experiment with other techniques from existing supply chains – just as long as it’s a financially sustainable experiment. 

Enjoyed this? Then read our article carbonic maceration and biodynamic farming.

Perfect Daily Grind

Want to read more articles like this? Sign up for our newsletter!