Investing in a Caffeinated Planet – Part I

By: Nicole Kruz

Photo: Your Best Digs, CC by 2.0,

Across the globe, there are over 25 million farmers producing coffee. Many are smallholders in developing countries that rely on the crop for their source of income. In this 5-part series, I will examine the coffee crop in detail to determine how its production is linked to poverty. Throughout the project, I will also look at climate change to learn more about its implications for natural ecosystems and local economies. I am specifically interested in learning how a changing climate could perpetuate cycles of poverty in the world’s poorest coffee farmers and determining whether anything can be done to alter the poverty paradigm.

Coffee is… the second most valuable commodity exported by developing countries, worth around $19 billion USD in 2015.” ~ The Climate Institute, 2016

Coffee Basics

There are around 100 species of coffee within the genus of Coffea. All of these species are historically indigenous to Africa, particularly Ethiopia, and the Indian Ocean Islands, particularly Madagascar. For the interest of coffee producers, only 2 of these 100 species are useful for present-day commercial applications: C. arabica and C. canephora, the latter being known more commonly as Robusta.

The Arabica plant is widely considered to yield the highest quality coffee and makes up 70% of global production. It is estimated that within Africa’s native coffee range inside Ethiopia, there are still 3,000 – 4,000 varieties and cultivars of coffee available. Outside of Ethiopia there are only about a dozen.

Robusta comprises the remaining 30% of global production. Robusta plant tastes bitterer and contains 60% less fats and oils than the Arabica plant, and its caffeine content is twice that of its Arabica cousin. It is primarily used to produce lower quality products such as instant coffee, although it does make good crema and often finds its way into espresso blends. Varieties and cultivars of the Robusta species are not as widespread as that of the Arabica species. However, due to its stronger disease resistant properties, in recent years Robusta has been increasingly cross-bred with Arabica to produce several hybrid cultivars, and a handful of countries do also cultivate a mild Robusta variety.

The Arabica species is a large bush with dark green leaves. It grows slowly and produces white flowers and fruits known as coffee cherries. This species is quite susceptible to disease. Robusta is a smaller, lower-growing and shallow-rooted plant, which also produces fruits and flowers. Its fruits generate seeds that are slightly smaller than the Arabica plant. A finicky crop, the Arabica coffee plant grows best high altitudes between 3,000 – 6,500 feet (915 – 1,981 meters) in rich soil, whereas the Robusta plant prefers lowlands.

Both species require at least moderate levels of rainfall and partial sunshine to thrive. The Arabica plant prefers temperatures between 60 – 75 degrees Fahrenheit (15 – 24 degrees Celsius) whereas the Robusta plant flourishes under hotter temperatures between 75 – 86 degrees Fahrenheit (24 – 30 degrees Celsius).

Geographic Range & Distribution

The coffee plant is indigenous to Africa and can trace its origin back to Ethiopia. Legend holds that the country began cultivating the crop in 800 AD, after a goat herder discovered a plant with red berries that would animate his herd upon consumption. Over the centuries, this red berry plant – the Arabica species – was moved and replanted locally, eventually being exported to Indonesia by Dutch traders, where French missionaries then brought it to Europe and the New World. In the Americas, coffee producers went on to cultivate new or hybrid varieties and cultivars of the species. Interestingly, Coffea’s Robusta species was not planted much prior to the late 1800s, until coffee leaf rust decimated the Arabica crop.

Today coffee is grown in roughly 60-70 countries, the majority of which are situated between the Tropics of Cancer and Capricorn. Known as the Bean Belt, the region encompasses sections of Africa, South America, Central America, and Asia. The Bean Belt typically offers two climate zones – equatorial and subtropical. In the equatorial region, coffee is often cultivated at higher altitudes than in the subtropical region, which is characterized by a wet and dry season. Brazil, Colombia, Indonesia, Vietnam, Mexico, India, Ethiopia, Guatemala, Uganda, and Cote d’Ivoire are widely regarded as the top ten coffee producing countries in the world.

Harvesting & Processing

Once planted, coffee trees will take 3 to 4 years to mature and bear fruit. The coffee crop is typically harvested once a year. However, some countries are able to produce two yields in one season because of weather patterns. Coffee cherries are generally still harvested by hand, a process that is labor-intensive and time consuming. In recent years, some coffee producing countries, such as Brazil, have taken to mechanized harvesting to increase harvesting speeds.

There are two main ways to harvest coffee: strip pick and selective pick. Following the strip pick system, all cherries on a single branch are pulled off at once. In the selective pick system, only ripe cherries are removed. This work is done individually by hand and requires several weeks of rotation to complete the stripping of a single tree.

Once harvesting is complete, coffee cherries are processed quickly to prevent spoilage. Cherries can be processed either by the dry method or the wet method. The dry method is the historical processing norm and is still practiced in countries where water resources are limited. To process cherries using the dry method, producers spread the crop out on hard surfaces during the daytime hours and leave them to dry under the sun. To prevent dew collection or spoiling, the cherries are raked as they dry and covered at night.

Using the wet processing method, producers remove the cherry pulp to expose the outer parchment and inner bean using a pulping machine. The exposed beans are then transported to a large fermentation tank where they will soak for 12 to 48 hours. This step allows for the removal of a slick layer attached to the parchment still attached to the bean. Following fermentation, the beans are rinsed and placed out to dry. Irrespective of processing type, all coffee beans or cherries will need to dry out to the point that their moisture content drops to 11%.

Before being exported, hulling machinery removes the parchment layer from wet processed coffee and the entire husk from dry processed coffee. Some producers may then chose to polish the coffee beans, although this is not required. In the final step, processed beans are graded and sorted by size and weight to ensure they contain no imperfections or deficiencies (e.g., overly fermented, insect-damaged). Some countries sort beans by hand where others use machinery. 


[In the next installment of this series, available November 9th, Virginia Tech’s Center for Leadership in Global Sustainability alumni Nicole Kruz will discuss the connections between coffee and climate change.]