Although Coffee is the most popular beverage in the world, most people don’t know much about their morning cup of coffee. While coffee comes in a many different varieties, flavors, roasts, and growing conditions; most people don’t know that the vast majority of coffee comes from two basic types of plants. Arabica and Robusta plants make up basically all of the world’s coffee supply. Here we take a look at the differences between these two types of coffee.
Origins of Arabica:
To gain a full comprehension of the coffee varietals (varieties), it is important to start with an understanding of the biology and history of the plant. Coffea is a genus of the Rubiaceae family. It is a flowering shrub that generates the fruit called cherries. Inside the cherry are the two seeds erroneously called the coffee “bean” from which the drink coffee is extracted. The two commercially important species of the Coffea geneus are Arabica and Robusta. While there are many other species like Liberica, Excelsa etc exist, they are not commercially successful for different reasons such as insufficient yield, difficult to cultivate, or prone to diseases etc.
Coffea Arabica is one of the many species that is believed to have been indigenous to Ethiopia. Initially, according to history, herders mixed fruit of the plant with animal fat and used the concoction to nourish themselves during their long travels. African slaves carried the seeds of Arabica plant to Yemen where a tea was made from the cherries and their stimulating effects realized. Systemic cultivation of coffee took hold in Yemen for the first time and from there the rest of the world was introduced to this amazing beverage.
From the plants growing in Yemen, some were taken by the Dutch and planted in Indonesia on the island of Java. Since coffee had become such a sensation by this time one plant was even given to the King of France as a gift. The tree was planted in the King’s botanical garden. The original plant had died, and another one replaced it. Scientists in the botanical garden propagated more trees from the one that took root.
Different varietals of a plant species, and coffee is not exception, tend to occur naturally as a result of chance mutations and human intervention. Clipping from the French coffee plant, which became known as the “the Noble Tree” were taken to South America as well as to the island of Bourbon (not to be confused with the drink!) by the French. Offspring of the Noble Tree are classified as the “typica” variety of coffee plant.
A second important variety that developed out of Arabica species is known as Bourbon (after the island where it was discovered) and is said to be a natural mutation of the Typica. It is from these two varieties that most of the other commercially successful varieties that we consume now have been developed.
Arabica Plants, Variants & Coffee Characteristics:
Arabica makes up for roughly 61% of the world coffee production. This is because the drink produced from these plants is highly aromatic and sweet. Chocolaty, fruity and nutty flavours with slightly acidic tones show up well in Arabica coffees.Their highly sought after taste qualities means the varietals of Arabica coffees sell for the highest prices. Unfortunately Arabica plants are prone to the leaf rust disease which has pushed coffee cultivators to search for new varieties that are more resistant to disease.
The good quality Arabica plants prefer high altitudes with steep terrain and hence are grown at altitudes ranging from 2,000 to 6,000 feet above the level of the sea. The plants also prefer temperatures of 60 – 75° Fahrenheit with around 60 inches of rain annually. The trees can’t withstand heavy frost and their yield per plant is not very high. The difficult access, susceptibility to disease and low yield makes the Arabica varieties more costly to cultivate.
There are many varietals of Coffea Arabica tree. Some of the better known include the following:
- Typica: The typical plant has a conical shape with secondary branches that grow at a slant forming an angle of arounds 50 – 70° On its own, Tyica produces a cup of coffee that has great sweetness with a lively citrus acidity and cleanliness when the plant is cultivated at high altitude. The problem for cultivators with typica is that it has a low per plant yield and it succumbs to disease rather quickly. It is rare to find farms that only cultivate typica now due to these issues. However, numerous other coffee varieties have been developed from the Typica plant.
- Bourbon: this variety delivers roughly 20 to 30% greater yield per plant than Typica, but has a smaller harvest compared to most other commercially cultivated varieties. The bourbon plant is not as conical shaped as Typica and has fewer secondary branches. Its fruit is comparatively smaller but denser. The fruit matures rapidly and there is a greater risk losing it to rain and winds. The ideal results are obtained if cultivated at an altitude of 3,500 to 6,500 feet. Cup quality of the drink produced is exceptional like that of Typica.
- Mundo Novo: is a hybrid that developed naturally from Typica and Bourbon varieties. Initially discovered in Brail in the 1940s, the plant is rather hardy and disease resistant. It has a high per plant yield but requires more time for the fruit to reach maturity. Its ideal cultivation altitude ranges from 3,500 feet to 5,500. It produces cherries that are big and rounded with beans imparting sweet flavours, low acidity and a heavy mouth feel.
- Caturra:This is a mutation of Bourbon originating from Brazil. While delivering high yield, and good drink quality, it requires a lot of care and fertilization. It adapts well to almost all environments but thrives at 1,500 to 5,500 feet. The cup quality is enhanced with higher altitudes, however at the cost of yield per plant yield. Plants of Caturra varities do not attain the same height as Bourbon, so is at times called the semi-drawf plant. The size of the plant makes picking the ripe cherries by hand easier.
- Maragogype: is probably the most easily recognizable variety. It has really large sized beans, and are at times called “elephant beans.” The variety is a mutation of Typica and originated from Brazil. Even though it is a low yield plant, it is desired for the size of its beans. The beverage produced is rather sweet.
- Geisha: This variety was an instant hit as soon as it was discovered in 2004 in Panama. In their cupping sessions, farm owners noticed unique characteristics displayed by beans of a group of trees. Later in the year they entered the lot from the trees in the “Taste of Panama” competition. In addition to first position the coffee earned record setting prices from buyers at the auction. While the variety is very volatile and low yield, it delivers the most tasteful cup of coffee with its outstanding aroma and distinguished floral sweetness. Panama Geisha comes in rosewater, jasmine, apricot and orange blossom flavours.
- Blue Mountain: Its cultivation started on Blue Mountains in Jamaica, after which it is named, this varietal of Typica is preferred for resistance to berry disease. It prefers high altitudes and delivers a cup that has a mild flavour and no bitter taste. It is now also cultivated in Kona, Hawaii.
- SL28: was developed by botanists in Scott Laboratories in 1931 while they were looking for various mutations of Bourbon and Typica. With broad beans and leaves of copper colour, it is a low yield plant. However the cup qualities are highly regarded due to enhanced lemon acidity, sweetness and the complexity it offers.
- SL34: Another mutation of Typica and Bourbon varieties, created in 1930. It tolerates heavy rainfall at higher elevations and is liked for citrus acidity and full mouth feel it displays in a cup. However, it is inferior to SL28.
Origins of Robusta:
The Robusta species was not discovered until 1898; it too was found growing wild in what is now known as Zaire (originally Belgian Congo). The species was named after the Belgian horticultural house that initially marketed the species at the start of the 20th century. The name also indicates the more hardy nature of the plant itself and the greater “kick” the beverage produced from it delivers.
Robusta Plants & Coffee Characteristics:
The Robusta plant is more robust and better able to resist disease. It also better at tolerating warmer climates with tempertures of 75 -85° Fahrenheit and does not require steep slopes or high altitude to grow. Additionally, it produces a significantly higher yield per plant compared to Arabica. These facts make it cheaper and easier to cultivate.
Sadly the taste profile of the Robusta is not very desirable. It delivers around 50% more caffeine than Arabica and produces a drink that is bitter with a taste like burnt rubber. It also lacks the fruity or nutty tones, thus making it undesirable for specialty coffee. Robusta is mainly used in blends and instant coffees. It makes up roughly 30% of the total world supply of coffee.
While Robusta does not make as great a cup of coffee as Arabica on its own, it has carved a place for itself in the coffee world. It is a vital component of some of the most exclusive Italian espressos. In an espresso machine, Robusta coffees are prized for the thick crema they deliver. This is why in the very best Italian espresso blends Robusta has become an essential requirement.
Even though there are no significant Robusta varieties to speak of, some extremely expensive Robusta coffees are produced.. Kopi Luwak from Indonesia and Kapeng Alamid from Philippines are Robusta coffee beans which are consumed by the common palm civet (something resembling a cat), and pass out of their system undigested. Passing through the animal’s digestive system imparts some very special flavours to the beans. These beans are collected and marketed.
The Liberica species originates from Western Africa. Liberica trees tend to be strong trees that grow to become rather large. They produce seeds that are boat-like in shape and are larger than the oval Arabica and round Robusta seeds. Liberica makes up less than 2% of the world coffee production.