From Coffee Cherry to Green Bean: The Basics

Ever wondered how your coffee beans started life? Before they’re roasted, ground, and brewed, every coffee bean begins as a cherry on a tree—going through harvest, pulp removal, and drying. Understanding this journey helps explain why coffee tastes the way it does, and why some beans cost more than others.

A single coffee tree yields 3–5 kilograms of fruit, but only about one-fifth of that—roughly 0.6 to 1 kilogram—becomes usable green coffee beans. Turning coffee cherries into green beans is a labor-intensive, multi-step process that varies by region and method.

The Three Main Coffee Species

Most of the world’s coffee comes from just three species, each with distinct traits:

• Arabica (Coffea arabica): Accounts for around two-thirds of global production. Arabica plants are sensitive to extreme temperatures and inconsistent rainfall, thriving best in cool, high-altitude environments. The beans are oval and flat, and produce a cup with high-quality, complex flavours and aroma. Arabica is typically more acidic and nuanced than other species.
• Robusta (Coffea canephora): Known for its strong bitterness and low acidity, Robusta offers a harsher, earthier profile with less desirable aroma. It’s often used in blends for instant, frozen, and canned coffee. The plant is hardy—resistant to disease, growing quickly, and suited to lowland, hot climates. Its high caffeine content acts as a natural pest deterrent.
• Liberica (Coffea liberica): A minor player in the global market, Liberica makes up a tiny fraction of production due to its lower yield and quality. It’s rarely seen outside Europe. The beans are larger and have a unique, woody flavour profile.

Flat Beans vs. Peaberries

Inside each coffee cherry, you’ll typically find two coffee seeds (beans) that develop flat against each other—these are known as flat beans. But about 5% of the time, a cherry produces a single round bean, called a peaberry (or caracol). This occurs when one seed fails to develop, and the other grows alone, rounding out. While the difference is mostly visual, many roasters and drinkers report subtle flavour distinctions, with peaberries sometimes showing more concentrated characteristics.

How Coffee Cherries Become Green Beans

After harvest, coffee cherries must be processed to remove all outer layers—skin, pulp, parchment (also called the endocarp or ), and the thin silverskin —revealing the green coffee bean inside. There are two primary methods: washed and natural .

Washed Process

Used in countries like Colombia, Mexico, and Guatemala, the washed method accounts for nearly 70% of global production. Here’s how it works:

• Cherries are sorted and soaked to remove floaters (unripe or defective cherries).
• The skin and pulp are removed using a depulper.
• The beans are soaked again, and any remaining floaters are skimmed off.
• The beans (now covered in mucilage) are fermented in water tanks for half a day to a full day. This step breaks down the sticky layer around the parchment.
• After fermentation, beans are washed to remove mucilage residues.
• The beans are either sun-dried or machine-dried.
• Finally, a hulling machine removes the parchment layer, leaving the green bean ready for export.

Advantages: Produces beans with bright acidity, high clarity, and a clean cup. Fewer defects and less contamination from foreign matter. However, improper fermentation can lead to unwanted flavours, including over-fermented sourness or unpleasant odours. When done well, it highlights unique bean characteristics.

Natural Process

Common in Ethiopia, Yemen, and Brazil, the natural or dry process is simpler but weather-dependent:

• Whole cherries are spread out on drying beds under the sun.
• They’re regularly turned for even drying, a process taking about one to two weeks. When the fruits are ready, you’ll hear a rattling sound as you move them.
• Once fully dried, a mechanical huller removes the dried skin, pulp, parchment, and silverskin to reveal the green bean.

Advantages: Produces a cup with softer acidity and a more muted, rounded flavour profile. This method requires fewer resources and is ideal in regions with limited water. However, it’s highly susceptible to weather delays, and more prone to contamination from dirt, insects, or defective beans. Careful hand sorting before export is essential to maintain quality.

What Happens Next?

After processing, the green beans are sorted, graded, and packed into sacks or specialised containers for shipping worldwide. They’ll eventually reach roasters, who will transform them into the aromatic roasted beans used for brewing.

Frequently Asked Questions

What is the difference between Arabica and Robusta coffee beans?

Arabica beans make up around two-thirds of global coffee production and are known for their complex, high-quality flavours and higher acidity. They are more delicate plants, requiring specific climate conditions. Robusta beans, on the other hand, are harsher, more bitter, and contain more caffeine. They are easier to grow, disease-resistant, and commonly used in instant, canned, and frozen coffee blends.

What are flat beans and peaberries?

Flat beans are the typical coffee beans formed when two seeds develop side-by-side inside the coffee cherry, resulting in their flat, oval shape. Peaberries (or caracols) occur when only one seed develops inside the cherry, growing round instead of flat. They make up about 5% of all coffee beans and are sometimes considered to have more concentrated flavour, though this varies.

What is the washed coffee process?

The washed process involves removing the coffee cherry’s skin, pulp, and mucilage through water and fermentation before drying the beans. This method is used in countries like Colombia and Guatemala, and results in a cleaner, brighter, and more acidic cup. It accounts for around 70% of global coffee production.

What is the natural (dry) coffee processing method?

In the natural process, whole coffee cherries are dried in the sun without removing the pulp. Once dried, the outer layers are removed mechanically to reveal the green bean. This method is common in Ethiopia and Brazil, producing a softer, mellower cup but requiring ideal weather and careful sorting to avoid defects.

Which process produces more defects?

The natural (dry) process is more prone to defects due to exposure to weather, insects, and dirt during drying. The washed process generally results in cleaner beans with fewer flaws, but requires significant water and careful fermentation management.

How much coffee can one tree produce?

A single coffee tree typically produces 3–5 kilograms of coffee cherries per harvest, but only about 20% of that weight—around 0.6 to 1 kilogram—becomes usable green coffee beans after processing.

Recommended FrontStreet Beans for Origin Exploration

Explore the origins behind green beans with FrontStreet Coffee’s Yirgacheffe, Ethiopia Humbera, and Brazil Queen Manor. Yirgacheffe offers bright citrus and floral notes typical of washed Ethiopian beans, highlighting the washed process’s clarity. Ethiopia Humbera showcases fruity complexity from the birthplace of coffee. Brazil Queen Manor, often processed naturally, provides nutty, chocolatey tones that reflect the country’s dry-processing tradition. These beans let you taste how origin and processing shape flavour. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.