A large proportion of Millennials love coffee, and coffee drinks are more popular now than they were ever before. Do you know that humans helped this plant to travel and grow from its native Africa to Asia and Latin America? Arabs brought the beans to Italy through Venice’s ports, and the coffee house culture spread to the entire Europe and America from then on.
If you want to learn about the different types of coffee beans you can savor in your daily cup of coffee, continue reading the complete article.
Origin of Coffee Drinks
It is thought that some seeds of the Arabica trees were shifted from Ethiopia to Yemen in the middle of the 9th century and cultivated till the end of the 14th century by the Arabs. Indonesia started the production of Arabica coffee beans in 1699.
Arab scholars are credited with the first written records of coffee drinks prepared from roasted coffee beans and their effects on prolonging work hours. These drinks were first prepared in Yemen using the Arabica beans and spread to Turkey and Egypt and subsequently to the entire world.
They arrived in Europe through a Dutch trader in the 17th century and spread to the French, Spanish, and British colonies.
Coffee Botanical Classifications
Coffee plants range from small shrubs to tall trees, and their plant leaves can range from 1 inch to 16 inches in size. Hence there always exists a disagreement among botanists on the exact classification of coffee plants. Let us quickly understand a few basic terms so that the balance discussion will be clear to you.
In the case of higher plants like coffee, the species is defined as the collection of individuals who are capable of breeding with each other to produce viable offspring.
A variety produced by human influence. It is also known as a cultivated variety. This new variety can be through selection from an existing cultivated variety or a wild, naturally existing variety. A cultivar must be distinct, stable, and uniform in its characteristics. It must have the ability to retain the same characteristics on propagation with appropriate methods.
Out of the naturally existing varieties and cultivars, fruit yield and disease resistance are the two most important traits that make them commercially important and viable. Hence breed selection is an important aspect of the sustenance of the coffee industry. The selection criteria can include
- Resistance to diseases.
- Resistance to pests.
- Cup quality.
- Amount of Caffeine.
- Maturation Rate.
A hybrid may be described as an offspring (crosses) produced by cross-pollinating different species, subspecies, varieties, and cultivars.
Coffea Genus – Different Types of Coffee Beans
In a very loose definition, any tropical plant of the Rubiaceae family capable of producing coffee beans is a coffee plant. Botanists have described more than 120 species since the advent of the 16th century, classified into the Genus “Coffea.”
As you may know, botanical classification is done using the taxonomic hierarchy,
Family > Genus > Species > Subspecies > Variety > Form, etc.
The coffea genus is characterized by evergreen shrubs or small understory trees that have horizontal branching and opposite-leaved structures. Their fruits or cherries that grow along the branches have two seeds, known as coffee beans; convex shaped on one side and flat on the other. The flat side of the two seeds, with a groove, faces each other.
The maturation rate refers to the time required for the new plant to produce fruit. After the first flowering, the cherry takes about a year to mature. A coffee plant may take around five years to reach its full production of fruit, where it produces 10 pounds of cherries and 2 pounds of coffee beans per year. A plant is most productive between 7 to 20 years of age.
The Coffea genus’s original geographical distribution was restricted to African tropical humid regions and the islands on the western bounds of the Indian ocean. The four major regions are West, Central, and East Africa, and the Madagascar islands.
Let us now briefly know about the four most important species of coffee plants and their interrelationship before we dive deep into the details of the most commercially viable beans. These are Coffea arabica, Coffea eugenioides, Coffea canephora, and Coffea liberica.
Coffea arabica & its origins
The Coffea arabica species is also known as Arabica coffee and is written as C. Arabica. It originated as a shrub among the undergrowth of the trees in the forests of Southwest Ethiopia, South Sudan, and northern Kenya at 1300 to 2000 m altitude.
Studies have shown that it originated from the natural hybridization of C. canephora and C. eugenioides.
This species is also known as Eugenioides coffee and is written as C. eugenioides. It is thought to have originated from the Eastern portion of Africa from the present-day countries of the Democratic Republic of Congo, Uganda, Rwanda, Western Tanzania, and Kenya. Part of this area overlaps with the areas of origin of C.Arabica.
The species has lower caffeine content than C.Arabica.
Also written as C. Canephora, the species is considered one of the parent plants of C. Arabica. Robusta Coffee is the most important genetic type of this species, the other being Kouillou. It is thought to have originated in Central and Western sub-Saharan Africa. It has a higher productivity and caffeine content.
It is commonly known as the Liberian coffee and is written as C.Liberica. It is a plant native to Central and Western Africa, like the C. Canephora, in countries from Liberia to Uganda and Angola.
It is now naturalized in Asian countries like Philipines, Seychelles, Indonesia, Andaman & Nicobar Islands, and Malaysia.
These trees are very tall compared to most other species and frequently reach 20 m in height. The size of their leaves, cherries, and beans is also amongst the largest. The harvesting is done using ladders.
Liberica beans as different from other beans in shape due to the asymmetric geometry on two sides, which means that one side is shorter than the other, leading to a hook-like appearance. They have a higher resistance to the coffee rust disease and account for about 1.5% of the total commercial global coffee production in the world.
Due to their limited supply, they are priced on the higher end, with premium qualities carrying a much heavy price tag. Liberica coffee beans have a much lower caffeine content than Arabica and Robusta beans.
Coffee Excelsa, Coffea dybowskii, and Coffea dewevrei were earlier considered separate species but were reclassified in the year 2006 as the Coffea liberica var. dewevrei, where var stands for the variety.
Different Types of Coffee Beans
Let us now have a brief look at the different varieties among the main species and their main characteristics.
Arabica coffee beans
Arabica Plant is considered to be the first species to be cultivated for commercial use and may be defined as the dominant cultivar in modern times, with more than 60% of the total world’s coffee production. It is thought to have been produced by a natural hybridization event between C. canephora and C. eugenioides around 0.5 to 1 million years ago due to changing climatic conditions. The arabica plants were first cultivated in Yemen around the 12th century.
Wild arabica plants range from 9 to 12 meters in height, with an open branching system having 6 to 12 cm long leaves. It grows in countries that lie between the Tropic of Cancer and the Tropic of Capricorn (bean belt).
Currently, commercial cultivation is done in Latin America, many parts of Africa, Southeast Asia, China, India, and islands in the Caribbean and Pacific.
Arabica coffee trees grow best in areas with
- 1300 to 1500 altitude. They can be grown in much lower and higher altitudes, but the best coffee bean grows between 1300 to 1500 m. At higher altitudes, shades, and consequent lower temperatures, the process of ripening happens slowly but leads to a much better bean filling. This results in much denser beans that are more intense in flavor. Hence the longer ripening process leads to higher cup quality.
- Annual rainfall of about 1 to 1.5 meters, uniformly distributed in the year.
- Average temperatures are between 15 to 24 °C. The plants can tolerate lower temperatures than this range but are highly susceptible to frost. Arabica is better adapted to face colder climates than the Robusta. Their adaptation to warm climates is similar. The average air temperature has a big impact on the sensory profile of the bean. Many qualities like the fruity aroma and character, acidity, and other special and unique flavors have a strong relationship with the air temperatures. The presence of more ethanal and acetone in roasted coffee indicates lower temperatures during bean development. The presence of elevated temperatures leads to the presence of volatiles, mostly in the form of alcohols, aldehydes, hydrocarbons, and ketones.
- Shaded conditions are better.
- Commercial cultivars grow up to 5 meters in height. Even these are trimmed to 2 meters to facilitate harvesting.
Arabica Coffee Bean Types (Varieties)
The many Arabica varieties have two main origins in recent times – known as the Ethiopians and the Yemen accessories. Yemen accessories consist of traditional varieties like Bourbon and Typica, including their mutants like Caturra and derived varieties. These varieties are highly productive and produce a standard cup of coffee.
As you might have guessed, the Ethiopians are the mutants and derived varieties of the original Ethiopian coffee. At the same time, Yemen accessories are the mutants and derived varieties of the seeds originally transferred to Yemen.
The Typica variety originated from the plants taken by Dutch from Yemen to Java, while Bourbon originated from plants transferred by the French to Bourbon.
Another major variety of the Arabica bean type is commonly referred to as the Timor hybrid due to its natural presence on the island of Timor in Southeast Asia. It has a natural resistance to the coffee leaf rust disease. Its varieties are used in many breeding programs to induce rust resistance in other cultivars like the Catimor, Sarchimor, and Colombia.
You might have heard the term gourmet coffee, which has reference to the high-quality but mild coffee varieties of arabica beans like Colombian Supremo, Costa Rica, Tarazzu, Jamaican Blue Mountain, Ethiopian Sidamo, and Guatemalan Antigua.
Being an understory plant, it is impacted heavily by deforestation. Climate change also endangers productivity due to its heavy sensitivity to temperatures. In addition, with increased temperatures, the pests are likely to flourish in higher altitudes.
Robusta Coffee Beans
Robusta plants constitute about 35 to 40% of the world’s total coffee production. Coffee drinkers around the world agree that the Robusta bean has lower acidity, more woody and earthy, and less fruity flavors with a more bitter taste than the Arabica beans. The bitterness is attributable to the presence of pyrazine content.
The Robusta plant grows either as a shrub or a tree up to 10 meters in height. The flowering cycle is irregular and requires 10 to 11 months for the coffee cherry to ripen. It is more resistant to diseases and pests, has much higher yields, and contains less sugars and more caffeine content compared to the C.Arabica. The sugar content is 3 to 7% as against 6 to 9% in Arabica.
Robusta beans are favored for use in instant coffee, espresso beans, and fillers in ground coffee blends. This is because, in the Italian coffee culture, a powerful flavor is desired by most coffee lovers to give strength and finish. Hence high-quality robusta beans are used in espresso blends at about 10 to 15%. This results in a full-bodied taste and better cream formation.
100% single-origin coffees with robusta beans are ideal for pour-over iced coffee, cold brew, and espresso.
Drinking coffee with Robusta beans has other benefits, as these beans can be used as antioxidants, diuretics, stimulants, and antipyretics.
The mass cultivation of robusta coffee was started in the early 19th century due to the heavy damage to the C. arabica plantations in Asia by coffee leaf rust (CLR). It was introduced from the Belgian Congo to Java in 1901. This was followed by plantations in Ivory Coast, Guinea, Togo, and Uganda.
It now grows mostly in Vietnam. It is also grown in parts of Indonesia, India, Brazil, and Africa. Vietnam is the largest exporter of Robusta beans in the world.
Excelsa Coffee Beans
While excelsa beans are now classified as part of the Liberica coffee species, an excelsa bean differs from the liberica bean in many aspects. The liberica bean has a long oval shape and much higher levels of caffeine. Excelsa beans, in contrast, are small and round. Excelsa has a much higher resistance to common coffee diseases than Liberica. Their genetic markup is also substantially different.
There is a very limited production of the excelsa coffee bean type worldwide due to the higher cost of production (as the trees grow very tall), lack of an established commodity market, and standardized price. So it is either consumed in-house or blended with Arabica coffee and rarely sold as single-origin coffee.
Many coffee drinkers think that these beans produce coffee flavors and strengths that are weak for their liking, while other coffee enthusiasts find the flavor profile to be comprised of fruity and tart notes. The bean quality resonates well with both light roasts as well as the blends of dark roasts.
The major production of Excelsa beans happens in Southeast Asia in countries like Vietnam, India, the Philippines, Indonesia, and Malaysia.