The first in a series of short blogs to help you understand why you love the coffee you love!
My three favourite drinks, coffee, water and wine … i don’t profess to be a connoisseur of wine I am very aware of it’s complexity. In wine we use the term ‘terroir’, meaning the natural environment in which the grapes are grown and the characteristic taste and flavour imparted to the wine due to that environment.
The coffee ‘bean’, as it is called in its roasted and ready to grind and brew state, is the seed found inside the fruit of the coffee tree. It should come as no surprise that coffee also varies hugely from region to region and is influenced by ‘terroir’ in the same way.
With over 850 individual volatile aromatic compounds catalogued so far, over double that of wine, coffee is arguably more complex. As with wine, aromatic descriptions and tastes in coffee are simplified and grouped to help us describe them. we will explore this more later.
So what are the natural environmental factors? These include climate, topography, altitude and soil. Influencing the development of the coffee flavours and quality in different ways and creating complexity and character. This is most appreciable in speciality coffee, where careful handling and expertise from seed to cup preserves and enhances these unique qualities (more on this to come).
Climate & topography
Coffee is an evergreen shrub. It requires warm temperatures all year round (no frost) and good rainfall to grow. Thus it only thrives between the tropics of Cancer and Capricorn. (The top ten coffee-producing countries are shown in yellow). Rainfall and temperature determine the development of the beans which then affect flavour, character and complexity. Regions further from the Equator have cooler temperatures and the beans develop more slowly, which can result in more interesting and complex flavours. Rainy seasons determine the flowering and fruiting. When there are two annual rainy seasons rather than just one the coffee plants can produce double the annual crop, but sometimes to the detriment of quality. Where there is too much rainfall fruits become plump and squishy, developing too quickly for interesting flavours to develop inside the seed. A longer, slower growing season with one moderate rainy season, usually results in higher quality and more flavoursome beans.
Altitude is perhaps a more influential factor than you might think. Mountainous regions present more adverse conditions. Cooler temperatures and good drainage mean that plants are deprived of what they like most: warmth and water. This can override the general climate of the region. Coffee plants growing in more adverse conditions develop more slowly, resulting in a denser bean with more complex flavours. At the same time these adverse conditions make it harder for defects and diseases to flourish (both of which have catastrophic results in the cup). If you like, high altitude is a natural barrier that results in higher quality coffee organically, without the need for pesticides and other chemical interventions. At the same time, yields are naturally lower, explaining the higher price of these coffees. Flavour characteristics attributed by specific altitudes are as follows:
At 1500 metres above sea level and above coffees display complex characteristics such as fruity, floral and even spicy notes. For example, some of the finest coffee-growing regions of Ethiopia have altitudes of up to 1600 MASL, which helps explains their unique and flavoursome profiles. At 1200 MASL we often find notes of chocolate, vanilla and nuts. Coffee growing at 900 MASL may still be sweet, balanced and tasty but perhaps a little less interesting. At elevations below this, coffees are mild and very simple.
Whilst there is no evidence to show that soil types can affect flavour notes in the same way as altitude, it goes without saying that soil quality affects the health of the coffee plant, the yield and overall development of the fruit and seed (bean). Good soil management is essential to prevent overly stressed plants. Like most plants, coffee thrives in well-drained soil high in nutrients and free from weeds. Shade trees are a commonly-used traditional method of aiding healthy soil by preventing rain runoff and rapid evaporation. On-going weeding, and the foliage falling from shade trees, also acts as an natural organic fertiliser as it composts down.
So next time you are enjoying a delicious brew, consider its origin: the climate, the landscape, the altitude and the farmers who carefully cultivated their crop.