What affects the flavour of coffee? Which coffee tastes best?
Let me start from the other end and ask what does not affect the flavour of coffee. The colour of the bag does not, and neither does the name of the company printed on it. So what does count? There is no single answer, the subject runs deep, but let us start at the beginning.
Coffee is a fruit, and its flavour is shaped by how much sun it gets, by the soil, by rainfall and by the altitude it grows at. That is only a fraction of what goes into a coffee. Today, though, we are keeping it short.
1. The species
There are dozens of coffee species, but only two are farmed at scale: robusta and arabica. They differ in flavour and aroma. Robusta is earthier and sharper in its aromatics and usually bitter in the cup. Arabica is softer, with more pleasant acidity and more sweetness, and it is incomparably more complex aromatically. Notes of chocolate, strawberry, peach and flowers are nothing unusual in an arabica.
Everything below applies mainly to arabica
2. Varietal: the botanical variety
Arabica has many varieties, of which around 50 are well described and studied. The list covers both native varieties and hybrids, natural ones and those bred by researchers. Each variety carries its own characteristic aromatics, and some simply taste better than others. The varietals most prized for flavour are Pacamara and Geisha. You will find more detail and a full list of studied varieties on the World Coffee Research site.
3. The growing region
This is where everything from the introduction comes in: climate, soil and altitude. All of it shapes flavour. Every coffee region has its own character, which is why coffee from Ethiopia tastes nothing like coffee from Brazil. That said, with modern processing in fashion (anaerobic fermentation and the like), a coffee from Colombia can now taste like a classic Kenyan. There are still broad expectations of what a coffee from a given region will do, and what we look for as drinkers. Briefly:
Central America: usually medium acidity and high sweetness.
South America: sweet coffees, low acidity, chocolate and nut notes.
Africa: complex coffees with high acidity and high sweetness, fruit and floral aromatics.
Asia and Oceania: low acidity, medium sweetness, earthy and herbal aromatics.
4. Processing specialty coffee
Processing methods in specialty coffee
Processing covers everything that happens to the coffee fruit up to the point where you have finished green coffee. There are two main methods, wet (washed) and dry (natural).
Coffees processed by the wet (washed) method are cleaner and lighter in the cup, with higher acidity and less sweetness. Washing interferes less with the flavour of the coffee itself.
Coffees processed by the dry (natural) method are sweeter, lower in acidity, heavier in the cup and bigger in body.
There is also a method that sits between the two, honey, which gives less ripe fruit character than a natural, high sweetness and lower acidity than a washed coffee.
Then there are modern processing methods, which affect flavour and aroma enormously.
Anaerobic fermentation: intense acidity, smooth texture, floral and cinnamon notes.
Lactic process (processing with lactic acid bacteria): dairy notes, high acidity, unusual fruit character.
Carbonic maceration: winey, fermented aromatics, the sweetness of ripe strawberries, raspberries and banana.
5. Roast level
Roast level describes the state of the beans after roasting, and we describe it by the colour of the roasted coffee. The darker the colour, the harder the coffee has been roasted. There are three main types:
- Light: the coffee keeps the most of its natural aromatics and takes on the least from the roast. In the cup, higher acidity, medium sweetness, low bitterness.
- Medium: the coffee still holds plenty of natural aromatics, but more of the roast starts coming through. In the cup, medium acidity, high sweetness, medium bitterness.
- Dark: little natural aromatic character is left and far more comes from the roast. In the cup, low acidity, medium sweetness, high bitterness.
The darker the roast, the less acidity and the more bitterness.
Roasting faults
Coffee roasted too light tastes earthy and beany, with an unpleasant sourness. Coffee roasted too dark, with oil on the surface of the beans, has no natural aromatics left, tastes of wood and carries a very high, blunt bitterness. Low quality coffee is most often roasted this way, to cover its defects. If you prefer a cup without obvious sourness, have a look at our lowest-acidity coffees.
So which coffee will I actually like?
A short guide to finding the coffee that suits you
Milk coffees
If you drink your coffee with milk, pick something from the Americas or an arabica and robusta blend, roasted medium or dark. Darker roasted blends of American and African coffees are worth a try too <3
(find them here)
A sweet coffee that works for everything
A medium roast from Brazil
(find it here)
Gentle bitterness and low acidity
South American coffees will suit you, usually naturally processed, roasted medium
(find them here)
Intense, low acidity
Most coffees from the Americas and from Asia, roasted dark, are the ones for you. Dark roasted arabica and robusta blends work well here too.
(find them here) or (here)
Fruit, and I am not scared of pleasant acidity
African coffees will do the job, roasted light or medium. For a gentler way in, a kind of prelude, try light roasts from Central America.
(find them here)
I prefer tea, but I like coffee too
Choose a light roast from Ethiopia and brew it through a thick filter
(find it here)
Dry and savoury
Asia is the place to look, choosing between an arabica from Indonesia and one from India. Medium roast.
(find it here)
In summary
The best way to learn about coffee flavour is to taste your way through as many coffees as you can. Write down what you notice and come back to those notes later. You will be surprised how much changes.
