Four types of coffee beans are currently sold on the world markets: Arabica, Robusta, Liberica, and Excelsa. Bright Arabica is the coffee that’s used most. Hearty Robusta is also popular.
The difference between Arabica and Robusta beans
Arabica (Coffea arabica)
Arabica coffee is the world’s favorite coffee, making up around 60 per cent or more of all the coffee grown. It originated in Ethiopia and was sent to Arabia (Yemen today) in the seventh century. The Arabs adored the bean so much that it eventually took their name.
Arabica has a pleasant, delicate taste. The coffee is smooth, not bitter, and can have a complex flavor profile that might feature notes of fruit, flowers, and wine. Because of their delicacy, Arabica beans pick up character from their home terroir, or soil. The soil, climate, and elevation all shape the taste of the coffee.
Many coffee drinkers take Arabica black so they can taste the full profile. Arabica is best served hot and suffers when cold.
Most gourmet or high-end coffees sold in the U.S. are made from Arabica beans. However, the name of the bean alone does not represent quality. While Arabica beans are grown around the world, most production is in Latin America and particularly Brazil.
Robusta (Coffea canephora)
Robusta, comprising 25 per cent of the world’s coffee production, contains twice the caffeine of Arabica beans with a stronger, more acidic flavor. Their flavors are reminiscent of grain, peanuts, or chocolate. Also originating in Africa, these beans are still grown there, as well as in Indonesia and Vietnam.
Robusta’s fans love its strength and caffeine. Its detractors say it tastes burnt. Robusta takes cream and sugar better than Arabica and makes a better iced coffee. The best Robustas have smooth textures and a hint of chocolate.
Because of their relatively low price, Robusta beans are often used in instant coffee and budget coffee brands. They are also frequently mixed with Arabica beans to achieve a stronger taste, more caffeine content, or just to save money. Robustas are more popular in Europe, the Middle East, and Asia—places where strong coffee is the cultural norm.
What is the difference between Arabica and Robusta?
In the U.S., Arabica is the high-end coffee and Robusta the bargain brand. Robusta has an intense taste, which may be described as burnt or rubbery. Robusta also has twice the caffeine. It costs half as much as its cousin Arabica. This low price is because it is easier to grow, has higher yields, can grow in more places, and has greater resistance to disease, fungus, and insects.
Arabicas have 60 per cent more lipids and twice the sugar of their cousin. These lipids contribute to aroma and shape the changing flavor of the bean as it roasts. Sugars undergo the Maillard reaction when roasting, which creates a depth of subtle flavors. These components lead to a variety of delicate flavors in the bean.
Sometimes these two are blended, and this is typical of the best espresso beans. Italian roast coffee often uses some Robusta in an Arabica base because the Robusta increases the quality of the crema on top of the coffee. Other blends are made to reduce costs.
We explore the taste differences between Arabica and Robusta, and the science behind them, in another post.
Lesser known beans
Liberica (Coffea liberica)
Liberica beans are from Africa, taking their name from Liberia. However, today they are mostly grown in Indonesia, Malaysia, and the Philippines. These beans make up two per cent of the coffee grown (but 95 per cent of the coffee grown in Malaysia is Liberica). Today, Liberica is only grown in a few small places and cannot increase production to match a global market.
Liberica coffee has a complex taste, including floral, smoky, and woody flavors. (Those who dislike it say it tastes of burnt garbage.) Individual beans can be wildly inconsistent, so quality control is difficult. Some roasters include Liberica as part of a blended coffee to showcase the diverse flavors of the beans.
Your best bet to find a cup of Liberica in the U.S. is to go to a market that serves Filipino immigrants and ask for Kapeng Barako or Barako coffee.
Excelsa (Coffea liberica var. dewevrei)
Excelsa beans, grown in small numbers, are not used much outside Southeast Asia where they are grown. Excelsa is known for its delicate flavor, low caffeine, and complex flavors. It tastes tart and fruity, but also offers a grounded depth. Sometimes you can find Excelsa beans in blends or from specialty coffee roasters. Most of the time you would need to take a trip to Southeast Asia.
Charrier (Coffea charrieriana)
A newly discovered species called Charrier, the first naturally caffeine-free coffee in central Africa, has been discovered in Cameroon. It was discovered in 2008 and is not yet in commercial production. Look for it in the future to be the next big thing to come out of the industry.
What is a coffee variety?
A variety represents a subspecies of a coffee type. Some varieties will take on different characters when grown in different locations, and these bean/location combinations are often given different sub-varietal names, even though the plants are the same.
Arabica contains several famous varieties. Typica is the normal (or typical) variety of coffee. It gains sub-species names when grown in different locations, e.g. Kona in Hawaii, Java in Indonesia, and Jamaica Blue Mountain.
Bourbon, another popular variety, is a mutation of the Typica plant that was found on the island of Bourbon (now Reunion) in the Indian ocean. Bourbon makes more cherries than others and has spread around the world.
Gesha (or Geisha) is the original Arabica from Ethiopia. It has a natural resistance to coffee rust and began to be cultivated for large-scale production in the 1950s. Today it is mostly grown in Panama.
What are the types of coffee bean roasts?
Much of the taste of coffee comes from how it is roasted. Roasting is needed to bring out the flavor. From a light toasting to an oily black charring, roasting shapes flavor.
Light roasts have the highest caffeine and are roasted for the shortest time. A light roast on a good Arabica bean will showcase the origin and type of bean very clearly. Examples of light roasts include cinnamon (blonde) and light city.
Medium roast is the most common roast in the U.S. It makes the bean slightly sweeter and at this point acidity, flavor, and aroma balance well. Medium roasts include breakfast, American, and high.
Medium-dark roast darkens the bean a little further to bring out the roasted taste, reaching a point of bittersweet flavor. The raises the levels of flavor and aroma and removes most acidity. Full city is the classic medium-dark roast.
Dark roasts take the bean to the edge where you taste the roast completely and little of the bean. These bitter roasts are common in Europe, where their lower acidity and caffeine are appreciated. The darkest roasts cause the bean to crack and release its oils. Some of these roasts are espresso, French, Viennese, European, and Italian.
Choosing your coffee
The bean you choose is a matter of personal taste. The fun part is exploring all the types of coffee beans, the regions they hail from, and the roasts. Your journey starts with the main crops: Arabica and Robusta. It then travels the world.