Coffee Tree: Let’s Dive Into Science!
We live in a world dominated by stimulating caffeine sips. But what lies at the bottom of our unceasing daily coffee routine? The coffee plant. It encapsulates the essence of our mornings with its luscious leaves and bountiful fruits.
Tracing its roots to antiquity, the coffea tree was initially cultivated in the lush landscapes of Ethiopia. Today the core coffee growing regions lie within the tropics and subtropics. Coffee trees flourish in various regions worldwide, especially in the Coffee Belt— Earth’s equatorial zone.
Every sip of coffee unfolds a narrative — from the tree’s inception in far-off lands to the nurturing hands that foster its growth. Join us on a journey through time and learn more about the coffea tree and the anatomy of the precious cherries that give us our flavorful brews.
Exploring the Morphology of a Coffea Tree
Coffee beans come from a coffee plant. Coffea plants can grow into either trees or shrubs, depending on their variety and cultivation methods. The coffee plant can reach between 10 to 30 feet in height but is pruned for easier management and better yield.
In general, coffee plants tend to be bushy and resemble a shrub or a small tree. They can reach 4 m when domesticated or 9 m in the wild.
“The coffee plant belongs to the Rubiaceae family, which includes well over 13,000 different species of trees, shrubs, and even herbs. We get coffee from the Coffea species. It is a perennial shrub but is often called a tree since it reaches heights of 20 feet or more.”
Coffee plants have slender trunks with branches covered in dark green, waxy leaves (1). The leaves are extremely important for the coffee plant, as this is where the photosynthesis happens. After three to five years of growth, the coffee bush grows delicate white flowers during the flowering season.
These fragrant flowers bear a resemblance to jasmine.
After about six weeks, the flowers turn into small fruits called cherries. Depending on the coffee bean types, the cherries can vary from vibrant red to yellow color. Every cherry holds two beans.
Coffee plants have a lifespan of 30 to 40 years, though certain varieties can survive even longer.
Time To Learn The Anatomy Of A Coffee Bean
If you ever wondered where does the coffee tree originate from, or about the features of Arabica and Robusta, you can explore our additional articles.
Interesting fact: Studies have shown that arabica coffee’s genetic diversity is lower than robusta coffee due to its narrow genetic base associated with autogamy, evolution, and domestication (2).
But what do coffea beans look like? Coffea beans look small, hard, and round. They usually have an oval or rounded appearance and measure from 1/4 in to 1/2 in in length.
The outer skin, known as the exocarp, surrounds a thin layer of pulp called the mesocarp. Enclosed within these, is a pectin layer named the mucilage, surrounded by the hull, also referred to as the parchment. The parchment contains two beans, side-by-side. The beans are covered by the epidermis, which is a thin membrane. It’s also called the silver skin. Finally, there is a bean in the centre, also called endosperm.
The husk, or a coffee cherry’s outer layer, must be removed to reach the bean. The bean has a smooth brown surface, but the exact shade depends on the roast level.
Coffee beans are dense, hard, and exhibit a firm texture, with a groove running the entire length of one side of the bean. This groove is used to identify the orientation during the roasting.
Final Thoughts
The coffea tree is a source of aromatic beans we can’t imagine our life without. It traces its origins from Ethiopia to today’s global presence. The complex journey it undertakes — from cultivation and harvesting, to roasting and brewing — culminates in the cups of coffee we eagerly savor.
FAQ
Yes, you can grow your own coffea tree. You can buy a coffee plant in a pot or grow coffee from a seed. Soak it overnight and sow it in moist compost if you want to grow it from seed. Don’t place it too deep, but stick to the surface. The seed will take six to eight weeks to germinate.
Plants called Coffea can grow as trees or shrubs based on their variety and cultivation methods. The coffee plant can reach between 10 to 30 feet in height but is pruned for easier management and better yield. Generally, coffee plants tend to be bushy and resemble a shrub or a small tree.
Kentucky coffeetree is a relatively rare tree native to North America, and it isn’t related to coffee plants. The name comes from the use of its seeds as a coffee substitute by early American settlers. Kentucky coffee trees are either exclusively male or female. Its wood is valued for strength and durability and was used to make railway sleeper cars. It has large leaves, greenish-white flowers, and coarse branches and can reach 90 feet.
Yes, you can drink coffee from a Kentucky coffee tree. However, this tree’s leaves, seeds, and pulp are poisonous to living things. The alkaloid cystisine is very dangerous but it could be neutralized while roasting. So, the seeds from this tree must be roasted and ground to make coffee. The brew is pungent, bitter, and worse than regular coffee beans. What’s more, the leaves have been used as fly poison.
References
- What is coffee? (n.d.). Www.ncausa.org. https://www.ncausa.org/About-Coffee/What-is-Coffee
- Herrera, Isabel Rosanna Cedano. “Genetic Diversity of Arabica Coffee (Coffea Arabica L.) Collections.” Ju.Edu.Et, 7 Oct. 2021, www.academia.edu/56393109/Genetic_diversity_of_Arabica_coffee_Coffea_arabica_L_collections.
