Types of Coffee Plants – Part 1
So, we all know what a roasted coffee bean is but, what is coffee? And what types of coffee plants are there? In this series we will discuss coffee from its beginning and the varieties available around the world.
Where does coffee come from?
According to Merriam-Webster the definition of coffee is:
cof·fee /ˈkôfē, ˈkäfē/ a beverage made by percolation, infusion, or decoction from the roasted and ground seeds of a coffee plant.
That coffee plant is actually a tree where coffee cherries grow along the branches. Coffee trees are pruned short to conserve their energy and aid in harvesting. Each tree is covered with green, waxy leaves growing opposite each other in pairs. Because it grows in a continuous cycle, it’s not unusual to see flowers, green fruit, and ripe fruit simultaneously on a single tree.
It takes nearly a year for a cherry to mature after first flowering, and about 5 years of growth to reach full fruit production. While coffee plants can live up to 100 years, they are generally the most productive between the ages of 7 and 20. The average coffee tree produces 10 pounds of coffee cherry per year. This equates to 2 pounds of green beans.
All commercially grown coffee is from a region of the world called the Coffee Belt. The trees grow best in rich soil, with mild temperatures, frequent rain, and shaded sun.
What is a coffee cherry?
The beans you brew are actually the processed and roasted seeds from the coffee cherry.
The coffee cherry’s outer skin is much like a cherry you buy in the grocery store. Beneath it is a thin layer of pulp, followed by a slimy layer of pectin. The beans themselves are covered in a paper-like envelope commonly referred to as parchment.
Inside the parchment, side-by-side, lie two beans, each covered separately by yet another thin membrane. This is generally referred to in the coffee trade as the silver skin.
In about 5% of the world’s coffee, there is only one bean inside the cherry. This is called a peaberry (or a caracol, or “snail” in Spanish), and it is a natural mutation. Some people believe that peaberries are actually sweeter and more flavorful than standard beans. Because of this, they are sometimes manually sorted out for special sale.
The botany behind the bean:
Coffee traces its origin to a genus of plants known as Coffea. Experts estimate that there are anywhere from 25 to 100 species of coffee plants.
In the coffee industry, there are two important coffee species — Arabica and Robusta.
Coffea Arabica — C. Arabica
Varieties: Bourbon, Typica, Caturra, Mundo Novo, Tico, San Ramon, Jamaican Blue Mountain
Coffea Arabica is descended from the original coffee trees discovered in Ethiopia. These trees produce a fine, mild, aromatic coffee and represent approximately 70% of the world’s coffee production. The beans are flatter and more elongated than Robusta and lower in caffeine.
The better Arabicas are high grown coffees — generally grown between 2,000 to 6,000 feet above sea level — though optimal altitude varies with proximity to the equator.
The most important factor is that temperatures must remain mild, ideally between 59 – 75 degrees Fahrenheit, with about 60 inches of rainfall a year. The trees are hearty, but a heavy frost will kill them.
Arabica trees are costly to cultivate because the ideal terrain tends to be steep and access is difficult. Also, because the trees are more disease-prone than Robusta, they require additional care and attention.
Coffea canephora — C. canephora var. Robusta
Most of the world’s Robusta is grown in Central and Western Africa, parts of Southeast Asia, and in Brazil. Production of Robusta is currently increasing due to cost and demand.
Robusta is primarily used in blends and for instant coffees. The Robusta bean itself tends to be slightly rounder and smaller than an Arabica bean. Robusta has a lower acidity content. But they are known for having a slightly bitter taste in addition to their woody, earthy flavor.
The Robusta tree is heartier and more resistant to disease and parasites, which makes it easier and cheaper to cultivate. It also has the advantage of being able to withstand warmer climates, preferring constant temperatures between 75 and 85 degrees Fahrenheit, which enables it to grow at far lower altitudes than Arabica.
It requires about 60 inches of rainfall a year and cannot withstand frost. Compared with Arabica, Robusta beans produce a coffee which has about 50-60% more caffeine.
Now, let all that information sink in while you keep an eye out for the next blog in this series. In Part 2 we will take a closer look at the varieties of coffee within these two species. Meanwhile, be sure to stop and grab a bag of your favorite beans to keep you warm on these winter mornings!