Read on to find out why we include the altitude on our coffee bags and why it is important to speciality coffee growth.
If you’ve picked up a bag of our coffee (or indeed any from other reputable speciality coffee roasters), you will have noticed that we include detailed information about our beans. We believe this to be important to all of our customers, not just the most discerning speciality coffee drinker, because understanding the story is a big part of an enjoyable experience.
This information often includes the altitudes at which the coffee has been grown. The question we’ve often been asked is why? As it turns out, altitude has played an important part in the evolution of coffee plants and has shaped the very fabric of the coffee industry. With that in mind, let’s look at the reasons why altitude is one of the most crucial factors in producing coffee to the highest standard.
OK, enough of the wordplay. Like any natural product, environment and climate play a crucial role in the health and well-being of coffee. Like many other natural crops, coffee plants have been harvested by humans and plucked from their original homes to be cultivated in other lands. If you read our recent article on Ethiopian coffee, you may remember me saying that it was the original homeland of coffee - or at least where it was first discovered as a crop. From then on, began a period of coffee planting in all corners of the Earth, which often resulted in failure, in European countries especially.
That’s not to say that there haven’t been successes in countries that have established themselves as major coffee growing regions like Brazil and Colombia. Why? Regardless of our interference, certain climates will always be far more conducive to high-quality coffee growing than others.
The correlation of elevation
It’s important to remember that coffee plants produce fruit (cherries) within which the beans are found, and these are made up of complex sugars, carbohydrates, acids and other elements. If you look closer at all of the world’s major coffee growing regions, there are several common climatic parallels shared by all of them. They each offer plenty of sunlight, rainfall, warmth but not too much, nutrient rich soils, and a certain level of elevation. The plant from which quality coffee is taken, Coffea Arabica, generally thrives at least 1,000 masl although there are coffee farms located as high as 2,800 masl (around 9,000 ft).
We can safely assume that temperature is important to flavour because it’s the same for just about any fruit or vegetable. Take grapes for example, the most naturally sweet of all the fruits. They ripen much quicker and taste even sweeter when they’re grown in hotter regions with lots of sunlight. Ever tried a Syrah wine from France (cool) and compared it to a Shiraz from Australia (scorching)? The same grape variety, produces vastly different wines.
‘The bean belt’, where nearly all coffee is grown, sits either side of the equator between the two tropic lines of Cancer and Capricorn, it’s essentially a stripe right across the hottest diameter on Earth. Being on the equator is great for coffee plants as they love consistent sunlight but they’re also delicate to too much heat, and nowhere near as robust as coconuts or bananas for example.
When you’re stuck on the equator and you can’t stand the heat where would you go? If you’re a coffee plant you can’t go for a dip in the sea because you’ll drown, so the only way is up. Brazil is the world’s most prolific coffee growing region and the average daytime temperature in the lowlands is around the 30 °C mark throughout the year. That average temperature 10 °C lower in the higher mountainous regions where coffee is grown.
What does this change in temperature mean for the beans? For starters, it helps to prevent the young fleshy cherries from baking in the searing heat, where 38 °C days are not uncommon. The cooler air also allows for slower maturation, which helps to produce more complex sugars. This explains the deeper flavours and brighter acidity we enjoy from beans that are grown at high altitudes. In fact, Central American regions like Honduras grade their beans by the altitude at which they were grown.
Temperature also plays a vital role in one of coffee’s most famous components and a characteristic that has had us humans hooked for centuries. Caffeine!
Caffeine is naturally produced by all coffee plants, although some produce more than others. We may know it as the vital lifeblood that we rely on to contend with the morning commute or a long list of emails. But to coffee plants, caffeine is the first line in the fight against being eaten by pests and insects.
Just take a look at the picture, coffee plants can look both beautiful and delicious, especially their cherries. This sight could be all too alluring for a hungry caterpillar or whatever other creepy crawlies you might find in the Amazon rainforest. But anyone who has eaten a roasted coffee bean, or even worse, a raw one, will testify that they are bitter and pretty gross. The cherries aren’t that much sweeter either!
Coffee plants use caffeine to protect themselves but the environment plays its own role too. Insects and rodents may thrive in the warmer climates of the lowlands but the higher you go, the less they appear, and the same goes for bacteria.
Coffea Arabica’s less appealing cousin, Coffea Robusta, can stand the heat and the many of the ordeals faced at lower altitudes. The reason is that it has a much higher content of natural caffeine.
Coffea Robusta plants generally thrive below 1000 masl and produce beans of lesser quality. That’s not to say that robusta beans are entirely undesirable, as many coffee drinkers appreciate them being added to espresso blends to give that added caffeine kick, especially in Italian roasted styles. We can all probably think of someone who, ‘likes to know they’re drinking a cup of coffee’ but you certainly wouldn’t want a brew made with 100% robusta beans.
As altitude increases, the cooler temperature and thinner air reduces the need to produce caffeine. Therefore, coffee plants grown in high places have less of the brash bitter flavours caused by caffeine, making for an all-round smoother cup.
The role of soil and water
Crops like coffee can encapsulate their environment, soaking up everything from the area in which they’ve grown. I often find when I open the seal on a fresh bag of Ethiopian green coffee that the smell almost transports me there, with its rich earthy and tropical aromas.
In places like Ethiopia especially, it is not uncommon for coffee farms to be found on the slope a mountain or a raised plain that was once an active volcano. This makes coffee cultivation pretty difficult with heavy machinery, so almost everything needs to be done by hand. These geographical factors also play an important role in determining the microclimate and environment around them. Altitudes in the major coffee growing regions can range dramatically, and farms that are less than 100 miles apart may be subject to completely different growing conditions.
Coffee plants love the nutrient enriched soils that are found high up on the slopes, which can dramatically change from one slope to another. These slopes also play an active role in helping to ensure that the water quality is at its most pure where coffee is grown. I guess that’s why companies like Evian and Fiji place so much emphasis on where their water comes from.
The slopes are also conducive to good flow and drainage of water, so the plants’ roots are less likely to suffer damage from sitting in water for too long. The cherries will also be less likely to fill up with too much water, which would have diluted their natural flavours.
So, we now know that coffee is like all crops in that is is affected by climatic and environmental changes, especially in regions with unique microclimates. We’ve also learned how altitude can massively affects what goes on outside and inside the coffee plant in terms of sugar and caffeine production. You can now get a good idea of what to expect from your next bag of coffee simply by checking the altitude on label.