Coffee Varieties

Within the species coffea arabica, which produces the vast majority of high quality coffee, there are a large number of varieties. As consumers have become more interested in the nuances of coffee flavor, more attention has been given to the effects of plant variety. Here are some of the major coffee varieties, which you might see listed on your bag of coffee.

Typica - Historically the most commonly grown coffee variety, Typica is the coffee against which all other varieties are judged. The ancestors of modern Typica originated in Yemen, but in the 17th and 18th centuries were taken through India to Java, then sequentially to Amsterdam, Paris, and Martinique, before being exported to Latin America, Brazil, and Africa. Now grown worldwide.

Bourbon - In the 18th century, a mutation of Typica was found growing on the island of Bourbon (now known as Reunión, located off the coast of Madagascar) which was higher-yielding and more disease-resistant than Typica. Bourbon is also known for its sweetness and citrus-like acidity. Now grown mainly in Central America, especially in Guatemala and El Salvador.

SL28 & SL34 - Bourbon plants were also exported to Tanzania, then Kenya by French missionaries. Of these French Mission Bourbon varieties, two were selected by a coffee research institute, Scott Labs, as being of particularly high quality and suited to the dry Kenyan climate. SL28 & 34 produce a full-bodied cup with good acidity, often with notes of blackberry and blackcurrant. Kenya grows the vast majority of this prized coffee.

Caturra - A mutation of Bourbon discovered in Brazil in 1935, which was higher-yielding still. Very common throughout Latin America. Caturra can produce high-quality coffee, but even experienced coffee tasters probably wouldn't be able to distinguish a Caturra from a Typica in a blind tasting.

Catuai - A hybrid of Caturra and Mundo Novo (which is itself a natural hybrid of Bourbon and Typica). Catuai is high-yielding, and can produce good coffee, but, like Caturra, is not particularly distinctive. Grown in Brazil and Latin America.

Pacamara - A hybrid of Pacas, a descendent of Bourbon, and Red Maragogipe, a mutation of Typica. Developed in El Salvador in 1958, and still mainly grown there. Pacamara plants produce extremely large beans and often display a jasmine aroma.

Ethiopian heirloom varieties - Ethiopia is the birthplace of coffee, and most Ethiopian coffee is produced from native plants. The genetic diversity of Ethiopian coffee plants is far greater than the diversity of cultivated varieties, and Ethiopian coffee can display a huge range of flavors.

Gesha - A wild Ethiopian variety of coffee which was exported to Panama in the 1960s for its disease-resistance, but was found to be relatively low-yielding and therefore was not widely planted. In 2004, the variety was rediscovered when La Esmerelda, a farm in Panama, won the national Cup of Excellence competition with their Gesha coffee. Since then, it has become specialty coffee's most sought after coffee, at one point selling for $170 a pound—unroasted! Gesha is known for its intense floral aromatics, reminiscent of its Ethiopian heritage.

Sources:
http://www.atlascoffee.com/pacamara.pdf
http://wetmill.tumblr.com/page/2
http://www.coffeereview.com/article.cfm?ID=161
http://www.terroircoffee.com/content/view/260/