Coffee can taste like jasmine, peach, strawberry, citrus, chocolate or tropical fruit. Sometimes those flavours are so vivid that a first-time specialty coffee drinker might assume something has been added to the beans. Usually, that isn't the case.
A cup of coffee is the result of an extraordinary chain of biological and chemical processes. Genetics, climate and agriculture establish its potential. Fermentation and drying reshape it. Roasting transforms the green seed into something aromatic and soluble. Brewing then determines which compounds ultimately make their way into the cup.
Behind what appears to be a simple morning drink is a fascinating combination of agriculture, microbiology, chemistry and human decision-making. And understanding a little of that science can completely change the way we taste coffee.
Coffee Flavour Begins on the Farm
Coffee is the seed of a fruit. Before becoming the familiar brown beans we grind at home, coffee seeds grow inside cherries on trees cultivated across tropical regions of the world. Their flavour potential begins with genetics. Different coffee varieties can display noticeably different characteristics, just as different grape varieties do in wine. Gesha, for example, became famous for its intensely aromatic and floral character. Other varieties may lean towards stone fruit, citrus, sweetness or a heavier structure.
Then comes terroir. Altitude, temperature, rainfall, soil and growing conditions can all influence how the coffee develops. Even two farms growing the same variety in the same country can produce remarkably different results. But harvesting the cherry is only the beginning. What happens next can dramatically change what we eventually taste.
Fermentation Is One of Coffee's Most Fascinating Variables
Once coffee cherries are harvested, the seeds must be separated from the fruit and dried before they can be exported. Traditionally, coffee processing was often reduced to a few familiar terms: washed, natural or honey. Those categories remain important, but contemporary specialty coffee has become far more sophisticated. Fermentation naturally occurs during coffee processing as microorganisms interact with sugars and other compounds surrounding the seed. Producers can influence that process by controlling variables such as time, temperature, oxygen exposure and the environment in which fermentation takes place. Changing those conditions can change the sensory profile of the coffee.
A carefully processed washed coffee might emphasize clarity, florals and delicate acidity. A natural coffee can develop a heavier fruit character and greater sweetness. More experimental producers are pushing those boundaries further. Anaerobic environments, selected yeast strains, extended fermentation, temperature-controlled processes and thermal shock are now part of the vocabulary of modern specialty coffee. There are also co-fermented coffees, where fruits, spices or other fermentation inputs may be introduced during processing to intentionally influence the sensory profile. The resulting coffees can be astonishingly expressive. Strawberry, raspberry, lychee, passion fruit, watermelon and other flavours can become so pronounced that they challenge our expectations of what coffee is supposed to taste like.
But fermentation only creates part of the flavour potential. The coffee still has to be roasted. Roasting Is Chemistry in Action. Green coffee bears little resemblance to the finished drink. It is dense, relatively pale and lacks the familiar aroma of roasted coffee. Heat changes everything. As temperature increases during roasting, water evaporates and a complex sequence of chemical reactions begins. Sugars, amino acids and other compounds react and transform, creating many of the aromatic molecules we associate with coffee. One of the best-known processes involved is the Maillard reaction — the same broad family of chemical reactions responsible for many of the flavours created when bread develops a crust or food browns during cooking. Coffee roasting involves an enormous number of reactions occurring within a relatively short period of time. This is why roasting isn't simply about turning green coffee brown. It is about controlling energy.
The Roaster's Job Is to Reveal, Not Simply Create
Modern specialty roasters closely monitor variables including temperature, time and the rate at which temperature changes throughout the roast. Too much energy at the wrong moment can alter how a coffee develops. Too little development can leave unpleasant vegetal characteristics. Taking the roast too far can cause flavours generated by roasting itself to dominate the characteristics created at origin. The challenge is to find the appropriate balance for each coffee. This scientific approach is particularly relevant at 94 Celcius, an independent specialty coffee roaster founded in 2017 and based in Sainte-Julie, Quebec, in the Greater Montreal area.
Founder Marc-Alexandre Emond-Boisjoly comes from an academic background in biochemistry and pharmacology, and that scientific influence carries naturally into the roastery's precision-oriented approach to coffee. Its program ranges from clean washed coffees and approachable espresso to rare varieties and highly expressive experimental lots, working with producers including Wilton Benitez, Diego Bermudez, Elias and Shady Bayter, Brayan Alvear and Pepe Jijón. The objective isn't to impose one recognizable roast flavour on every coffee. It is to understand what is already present and find a roasting approach capable of expressing it. That distinction is central to modern specialty coffee.
Why Lighter Roasting Can Reveal More
Dark roasting creates familiar flavours. Chocolate, caramelisation, roast bitterness, smoke and heavier body can all become prominent as roasting progresses. Lighter roasting approaches coffee differently. Rather than maximizing flavours generated during roasting, the objective is often to preserve more of the characteristics associated with variety, origin and processing. A washed Ethiopian coffee might reveal jasmine, citrus and tea-like qualities.
A Colombian coffee could express stone fruit or berries. A carefully fermented lot might be intensely tropical. This doesn't mean lighter is automatically better. Roast level is another variable — and different approaches suit different coffees and different drinkers. But for someone interested in understanding terroir, variety and processing, lighter roasting can make the differences between coffees remarkably apparent.
From Understanding Coffee to Exploring It
One of the most interesting consequences of understanding how coffee flavour develops is that it changes the way people choose what to drink. Instead of searching for one favourite coffee and buying it repeatedly, some specialty coffee drinkers begin exploring differences between origins, producers, varieties and processing methods. A delicate washed Ethiopian coffee can demonstrate the influence of terroir and variety. An intensely fermented Colombian coffee can reveal just how dramatically post-harvest processing can affect flavour. A rare variety from Panama might offer an entirely different aromatic experience. Tasting these coffees side by side can be far more educational than simply reading about them. This is also why discovery-focused coffee subscriptions have become an interesting part of specialty coffee culture. At 94 Celcius, that idea is expressed through Club Expé, its specialty coffee subscription. Rather than automatically replenishing the same coffee every month, the program is designed around exploration, with subscribers receiving two changing single-origin filter coffees selected from the roastery's current releases.
The selections can move between different producers, origins, varieties and processing methods, allowing subscribers to experience some of the variables that shape flavour in a practical way. One month might demonstrate the clarity of a washed coffee. Another could introduce an unusual variety or a more expressive fermentation. Over time, those comparisons can help drinkers develop their own sensory vocabulary. Perhaps more importantly, they demonstrate that there is no single definition of what specialty coffee should taste like. For some people, the most memorable cup will be delicate, floral and tea-like. For others, it might taste intensely of berries or tropical fruit. Understanding why those coffees taste different makes exploring them considerably more interesting.
Brewing Adds One Final Experiment
Even after the farmer, producer and roaster have finished their work, another chemical process remains. Brewing is extraction.Water dissolves soluble compounds from ground coffee, and changing the conditions of that extraction changes what reaches the cup. Grind size affects surface area. Water temperature affects extraction. Mineral composition influences how compounds interact with water. Contact time and coffee-to-water ratio matter too.
This is why the same bag of coffee can taste dramatically different from one brewer — or even one recipe — to another. A small adjustment to grind size can make sweetness appear more clearly. Different water can change perceived acidity. Changing temperature can alter balance. For coffee enthusiasts, experimentation becomes part of the experience.
One Cup, Hundreds of Decisions
Perhaps the most fascinating thing about specialty coffee is how many decisions have already been made before we take the first sip. Someone selected a variety and planted it in a particular environment. A producer decided when the cherries were ripe enough to harvest. Those cherries were fermented, processed and dried according to another set of decisions. The green coffee was selected and transported. A roaster then developed a profile designed to express its potential. Finally, someone ground the coffee, heated water and brewed it.
What we describe simply as "peach", "jasmine", "strawberry" or "chocolate" is actually the sensory result of this entire chain. Understanding science doesn't make coffee less romantic. If anything, it makes a great cup more remarkable. Coffee sits at an unusual intersection of biology, agriculture, microbiology, chemistry and craft. Whether that exploration happens by following a particular producer, comparing processing methods or simply tasting a different coffee each month, every new cup offers another opportunity to understand how those elements interact. Sometimes the most interesting question isn't whether coffee tastes good.
