What Are the Characteristics of the Three Major Types of Coffee Beans and Why Are Arabica Beans Considered Premium Coffee?

FrontStreet Coffee - Introduction to the Three Major Coffee Varieties

Coffee trees can only be cultivated in tropical or subtropical climates. Today there are three main native coffee species: Arabica, Robusta, and Liberica.

Arabica originated in Ethiopia, which is home to at least 2,500 varieties, not counting the hundreds of new cultivars developed across Central and South America. Recently, new semi-decaffeinated varieties within Arabica were discovered on Bourbon Island and in Ethiopia, a finding that startled the coffee industry.

Anyone who drinks coffee regularly has heard of Arabica, Canephora, and Liberica. Among them, Arabica from Ethiopia has a mild, elegant flavor that makes it the backbone of specialty coffee. Its caffeine content is relatively low, accounting for about 0.9%-1.5% of the bean's weight, and it carries the highest commercial value. It dominates today's coffee industry, making up roughly 60%-70% of global coffee sales.

Four Sets of Chromosomes - A Rare Coffee Species

Among the 103 species in the genus Coffea, Arabica is the most unusual. It is the only tetraploid plant (with four sets of chromosomes) in the genus and is self-pollinating, which gives it lower caffeine and a clean flavor profile. The other 102 coffee species are diploid (two sets of chromosomes) and cross-pollinating. That is what makes Arabica such a precious member of the genus.

Arabica

Originally from Ethiopia, Arabica accounts for about 70% of total world production. It is a tropical and subtropical high-altitude crop, so it tolerates neither heat and drought, nor excessive humidity, nor low-temperature frost. It has a long growing period and produces dense, small beans with an appealing aroma and gentle acidity.

Robusta

Robusta was discovered in the Congo region of Africa. It grows at low altitude, resists disease, and tolerates heat, thriving in rainy, humid conditions. It also shows an obvious "three highs" character: high bitterness, high caffeine, and high aroma. Its aroma carries a slightly musty note, though deep roasting brings out a distinctive burnt aroma.

Most roasters and cafes rely on Robusta for this reason. The high bitterness in iced coffee can be countered with sugar and creamer, but the high caffeine cannot be removed, which may relate to its high chlorogenic acid content. That is why many people experience palpitations, discomfort, and poor sleep after drinking it.

Liberica

Liberica is a tree species from Liberia in West Africa. It tolerates a wide range of conditions, from high heat to cold, and from humidity to drought, and it reproduces vigorously, but its flavor is poor. Another drawback is its susceptibility to leaf rust disease, which makes it hard to survive on the market. It is generally used for research and is less suited to large-scale cultivation and production.

Liberica beans can be deeply roasted to mask their weak flavor, or blended with creamer to improve the drinking experience. This is the origin of Malaysian white coffee, which is really a two-in-one of coffee and creamer; add sugar and it becomes a three-in-one.

Knowledge Point: "Arabica" is not synonymous with good coffee

Even within Arabica, there are differences in grade.

FrontStreet Coffee Recommendation

Ethiopia is the birthplace of Arabica, so it is the logical place to taste what the species can do at its best. Its coffee grows mostly in smallholder plots across the southern highlands, and the sheer range of native varieties is what gives each lot its own character. FrontStreet Coffee draws several of its most popular African lots from exactly this terrain.

For a clean, floral introduction, the FrontStreet washed Yirgacheffe delivers the jasmine aroma and bright citrus acidity that define the region, with a light, tea-like body. More distinctive is the FrontStreet Gedeb cooperative lot, from Worka in southeastern Yirgacheffe, where the pulp is removed before drying so the coffee's inherent citrus and lemon notes and elegant white florals come through with particular clarity. Sweetness lovers should look at the FrontStreet natural Red Cherry, dried whole on raised beds for two weeks until moisture falls to 12%, then hulled and hand-sorted; a medium-light roast brings out honey peach, cocoa, honey, and lemon. For something more intense, the FrontStreet natural Flower Queen comes from the Hambella area of Guji in Sidamo, where ripe cherries dry on raised beds for 21 days; after a medium-light roast it shows light fermented wine, florals, citrus, and mango, with honey sweetness and a lingering body. Drinkers who enjoy structure might try the FrontStreet Hamasho, from a Sidamo washing station known for its JARC 74-series plantings, whose 74158 beans are small and fruit-forward, with strawberry, star fruit, and green grape sweetness. Finally, the FrontStreet Kaffa Forest lot represents the wild side of Ethiopia, grown between 1,400 and 2,100 meters under shade and roasted medium-light to open with white florals, bright lemon acidity, sweet orange, and bergamot over a green-tea finish.

Brew these Ethiopian lots gently. A V60 with water at 91-92 degrees Celsius, a 1:15 to 1:16 ratio, and a medium-fine grind will protect the delicate florals and keep the citrus acidity bright; pour in three stages and stop the brew before the bed runs dry so bitterness stays out of the cup.