Coffee, an evergreen shrub of the genus Coffea in the family Rubiaceae, has a vast family, but only three native species—Arabica, Robusta, and Liberica—truly hold commercial value. Arabica is renowned for its elegant flavor and aroma, yet it is delicate and susceptible to leaf rust; Robusta has strong disease resistance, intense flavor, and high caffeine content, and is mostly used for instant and industrial coffee; Liberica has excellent adaptability but inferior flavor and circulates only in specific regions. Understanding the origins, characteristics, and market distribution of these three is the first step into the world of coffee. Front Street Coffee reminds you that only by starting from the bean variety can you better understand the flavor in your cup.

Coffee Bean Basics (Part 1)

The coffee tree is an evergreen shrub of the genus Coffea in the family Rubiaceae, mainly distributed in tropical regions; this family includes about 500 genera and 6,000 species in the tropics. Historically, coffee was often believed to have multiple medicinal effects, such as aiding digestion, refreshing the mind, stopping bleeding, reducing fever, and nourishing the body. Also well known in the Rubiaceae family is gardenia, whose fruit was dried and used as medicine very early on.

The Three Major Native Species of Coffee

There are about 40 species in the genus Coffea, yet only Arabica, Robusta, and Liberica produce coffee beans with commercial value, and they are collectively known as the “three major native species of coffee.”

1. Arabica (scientific name Coffea arabica)

Arabica originated in the Abyssinian Plateau of Ethiopia (today’s Ethiopian Highlands). In the early days, it was mainly used as medicine, and some Islamic couples regarded it as a secret remedy for regulating body and mind or as a stimulant. By the 13th century, people gradually developed the habit of roasting and drinking it; in the 16th century, it spread through the Arab region to Europe and eventually became a globally popular beverage.

Among all coffee, Arabica accounts for about 75% to 80%. It has outstanding flavor and aroma and is the only one of the three major native species that can be drunk directly. However, its resistance to drought, frost, and pests and diseases is relatively weak, and it is especially susceptible to coffee’s formidable enemy—leaf rust—so producing countries are actively carrying out variety improvement. Sri Lanka is a typical example: it was once a famous coffee-producing country, but at the end of the 19th century, due to a massive outbreak of leaf rust, its coffee estates were almost completely wiped out. After that, Sri Lanka turned to developing black tea and became known, alongside India, as a kingdom of black tea.

The main producing regions of Arabica coffee beans include South America (except parts of Argentina and Brazil), Central America, Africa (mainly East African countries such as Kenya and Ethiopia), and Asia (Yemen, India, and parts of Papua New Guinea).

2. Robusta (scientific name Coffea robusta Linden)

Robusta is a leaf-rust-resistant variety discovered in Congo, Africa, and its disease resistance is stronger than that of Arabica. People are accustomed to discussing Robusta alongside Arabica, but in fact Robusta was originally a mutant variety of Coffea canephora. Strictly speaking, the species that should truly be mentioned together with Arabica is Coffea canephora. However, today the name Robusta is deeply entrenched, and the public generally regards it as the same category as Coffea canephora.

Arabica coffee trees are suited to cooler, high-altitude tropical zones, while the high-temperature, high-humidity environments unsuitable for Arabica are precisely where Robusta grows. Robusta has a distinctive aroma (an off-flavor known as “Robusta taste,” which some find reminiscent of mustiness) and bitterness; adding just 2% to 3% to a coffee blend will give the entire cup a pronounced Robusta character. Its flavor is just that distinct and intense, and if you want to drink it directly, you may need some mental preparation. It is usually used in instant coffee (its extracted coffee liquid is about twice that of Arabica), canned coffee, liquid coffee, and other industrial coffee products. Robusta’s caffeine content is about 3.2%, far higher than Arabica’s 1.5%.

The main producing countries of Robusta include Indonesia, Vietnam, and West African countries centered on Côte d’Ivoire, Algeria, and Angola. In recent years, Vietnam has actively joined the ranks of major coffee-producing countries and incorporated coffee production into national policy (Vietnam also grows some Arabica coffee).

3. Liberica (scientific name Coffea liberica)

Liberica is native to West Africa. Whether in high or low temperatures, humidity or dryness, it has strong adaptability, but it is not resistant to leaf rust, and its flavor is inferior to Arabica. Therefore, it is traded domestically only in some West African countries (such as Libya and Côte d’Ivoire) or grown for research purposes.

About 65% of the coffee circulating in the world market is Arabica

According to statistics from the International Coffee Organization (ICO), excluding domestic transactions within coffee-producing countries, about 65% of the coffee circulating in the global market is Arabica and 35% is Robusta. Arabica beans are characterized by being slender and flat, while Robusta coffee beans are rounder, making them easy to distinguish by shape alone.

However, if hybrids of Arabica and Robusta are also taken into account—for example, the variety Variedad Colombia, which is the main variety of Colombian coffee and carries one-quarter Robusta blood, thus resisting leaf rust and yielding high output—and再加上 its mutant sub-varieties, the classification becomes even more complex. Some Arabica coffee beans are very close to the native species, while some Arabica beans are quite similar to Robusta. Even if the coffee name is the same (named after the origin), the flavor will differ as long as the cultivated variety is different.

Front Street Coffee suggests that after understanding the basic characteristics of the three major native species, choosing coffee beans based on specific origins and processing methods will make it easier to find the cup that suits your taste.

The above content is compiled by CoffeeHunters, a coffee news website.