COFFEE PLANT - ARABICA & ROBUSTA

Having been a regular coffee drinker since he was  10 and having worked for nearly three decades of his life, Grandpa has now settled in a coffee estate close to the nature he admires and even closer to the plants that produce his daily cup. His thoughts of managing an estate have been hovering for some time when he decides to talk to his friend, Mr. Krishna who has established his life in his own estate since a few years. Rohit, his grandson, who has learnt a little about the coffee plant from his Grandpa is also inquisitive to explore the plant life and joins along.

 

As the two old friends start their conversation over a cup of coffee, Grandpa immediately asks his friend to explain about the coffee plants and the types of coffee produced. Mr. Krishna, with all his experience, explains to Grandpa everything he wants to know while sipping their drinks. 

“The coffee consumed around the world comes from two majorly grown plant species – Coffee Arabica & Coffee Canephora (also called Coffee Robusta) although there are over a 100 known species and new ones are still being discovered.

“A lot of research is being carried out to protect the existing plant varieties from global warming and its consequences and also to discover new species that have desirable features that could be introduced to the existing plants to make them more resistant.

“While the scientists are busy looking for promising features in the new plant varieties, here is brief information about the coffee plant and the two main varieties grown to produce commercial coffee – Coffee Arabica & Coffee Robusta.

COFFEE PLANT

“A coffee plant is a woody perennial evergreen shrub that grows in the Bean Belt of the world. These regions offer the ideal soil and climatic conditions – temperature and rainfall for the growth of coffee.

“Coffee plant was first discovered in Ethiopia, Africa. Although native to the African regions, it is now cultivated in over 70 countries including Brazil, Vietnam, Mexico, Colombia, India and Indonesia.

DID YOU KNOW? Bean Belt or the Coffee Belt represents the area around the world where the coffee plant grows. It lies in between the Tropic of Cancer and Tropic of Capricorn.

“A coffee plant can grow up to 10 meters in height but are pruned for easy harvesting. Hence they grow as bushes or shrubs. The leaves are waxy, yellow to green in colour growing in pairs opposite to each other. The plant produces fragrant white flowers blooming along the branches, attracting pollinators, for a period of 3-7 days after the rainy season.”

DID YOU KNOW? The flowers blossom soon after the monsoon showers in South India. Rainfall severely affects flowering hence some countries that have two rainy seasons can expect blossom and harvest twice while few other countries with infrequent rains may find flowers, immature and mature cherries all together on the plant.

 

A sudden whiff of air comes when Rohit smells coffee flowers for the first time and says, “This smells like jasmine, strong and sweet.” Mr. Krishna tells Rohit that he is lucky to have experienced this as this lasts no longer than a week.

Image: From left to right - Coffee plants, flowers, raw coffee cherries and ripe coffee cherries

Mr. Krishna continues, “The flower eventually falls and the coffee cherries start growing in clusters at nodes. Coffee cherries are initially green in colour developing slowing in to bright red ripe cherries. Each cherry holds two seeds inside that are oval in shape.

COFFEE PRODUCTION

“The red cherries are harvested during the dry season and this is the first stage of coffee production. There is one major coffee harvest per year however some countries having favourable climates produce two harvests a year – a main crop and a fly crop. In India, we have only one crop every year.

“The coffee is further processed at various stages – Dry/Wet processing, Drying, Winnowing, Grading, Sorting and finally bagging and storing to get green coffee beans.

“The green coffee beans are roasted to perfection when it releases its aroma and then ground in various sizes based on the equipment used to brew and extract the decoction.

 “Now that you know a few basics about the coffee plant, here is a table explaining the difference between the two widely grown species – Coffee Arabica and Coffee Robusta,” said Mr. Krishna, pointing towards the chart that hung on his living room wall.

“Coffee Arabica mainly grows in Brazil (the highest producer), Ethiopia, Colombia and Mexico while Coffee Robusta grows in Vietnam (the highest producer), Africa, and Indonesia. Other countries like Tanzania, Congo and India grow both Arabica and Robusta.

DID YOU KNOW? Brazil is the only country in the world that grows Arabica coffee on a relatively flat land.

“The growth of a coffee plant is greatly influenced by several factors – soil, temperature, rainfall, altitude, which is why Arabica that is mostly grown on higher elevations tends to slowly develop the cherry producing a sweeter tone and Robusta, which can be grown from sea level to low elevations in hotter regions, has harsh tones.

“Robusta (‘robust’ as the name suggests) is highly resistant to major pests and diseases – coffee leaf rust and white stem borer, whereas Arabica is easily susceptible and hence requires high maintenance.

 “Cherries grow in clusters at each node. A Robusta plant outnumbers Arabica by 10 – 20 cherries per node which indicates that Robusta produces more coffee than Arabica. This proves why Arabica is priced twice as much as Robusta - the produce and labour cost involved.

“Despite significant differences between the two species and the kind of coffee they produce, they are consumed globally for the flavours exhibited. Those, who look for a mild, sweet taste, prefer Arabica and Robusta is a choice for those who love earthy, bitter, pea nutty overtone. Blends of Arabica and Robusta are commonly tried and tested to bring out new flavours in your cup.”

Grandpa along with Rohit returns to his estate driving his car, recollecting the conversation he had – things he knew a little about (coffee processing and roasting) and many more new facts about the coffee plant. He decides that he has to learn more about coffee processing soon and thus bringing Rohit along he meets his friend, Mr. Krishna, again the following week.

Isn’t it pretty easy to get the green coffee beans from the cherries? What is coffee processing? Does processing produce the coffee in our cup? Find out what Mr. Krishna explains about Coffee Processing and its types and how it’s done...

If you'd like to know more about the two majorly grown varieties of coffee here is a table which compares the two - 

	Arabica	Robusta
World Production	60 - 70%	30- 40%
Propagation	Mostly Seeds	Cuttings work best for Robusta
Leaf colour	Dark green	Pale green
Pollination/Fertility	Self-fertile, self-pollination	Self-incompatible, cross pollination
Maturation Time	6 -8 months	9 - 11 months
Susceptible to	Major coffee pests and diseases, frost	Drought
Temperature	15 - 24°C	18 - 30°C
Rainfall	1200 - 1800 mm/year	1500 - 3000 mm /year
Altitude	600 - 2000m , High altitudes & hilly areas	Sea level to 800 m
Bean Size & Shape	Large, oval or elliptical in shape	Smaller, rounder than Arabica
Caffeine %	1.50%	2.70%
Sugar and Lipid Content	Higher concentration	Lower concentration
Acidity	Higher acidity	Lower acidity
Taste	Sweet and soft	Harsh and strong
Tones	Sugar, fruit, floral tones	Grainy, earthy, woody tones

 

Image: Arabica coffee beans (Left) and Robusta coffee beans (Right)