Everything You Need to Know About Raw Coffee Beans

When you sip a great cup of coffee, you're tasting the end result of a long journey that begins on a tree. But how does a bright red coffee cherry turn into the green beans we roast? And why do some beans cost more, taste better, or grow only in certain places? This guide unpacks everything you need to know about raw coffee beans—the seeds of the fruit that fuel your daily brew.

A single coffee tree yields about 3 to 5 kilograms of coffee cherries, which in turn produce roughly one-fifth that weight in raw, green coffee beans—just 0.6 to 1 kilogram per tree. Turning those cherries into export-ready beans takes weeks, multiple steps, and many hands. Let’s break down how it works, from plant to parchment.

Coffee Species: Arabica, Robusta & Beyond

The majority of specialty coffee starts with the Arabica species. Making up around two-thirds of global production, Arabica plants prefer moderate climates—they struggle in extreme heat, cold, heavy rain, or drought. The beans are typically oval with a flat side, giving them a characteristic ‘flat bean’ shape, and are prized for their nuanced aroma and higher cup quality.

Robusta, on the other hand, is bitter, less acidic, and has a harsher, earthier flavour profile. It’s often blended into instant coffee, espresso blends for crema, or commercial canned coffee. Robusta grows well at lower altitudes and is far more resistant to pests and disease. A third, much rarer species—Liberica (or )—has poor cup quality and low yield. It’s mostly exported to Europe and rarely seen in Japan or specialty markets.

Flat Beans vs Peaberry: What’s the Difference?

A typical coffee cherry holds two seeds (beans) that sit facing each other, forming a flat surface where they touch—these are called flat beans . But about 5% of cherries produce just one round seed instead of two. That lone, rounded bean is known as a peaberry . Despite their different shapes, both flat and peaberry beans usually taste similar—any flavour differences come more from origin and processing than shape alone.

From Cherry to Green Bean: Processing Methods

Once harvested, coffee cherries must be processed to remove all outer layers—the skin, pulp, mucilage, and silverskin—leaving just the raw bean inside its parchment. There are two main methods: washed and natural .

Washed Process

In the washed method, ripe cherries are first sorted in water tanks to remove unripe or defective ones. The skin and pulp are stripped off using a depulper, then the beans are fermented in water tanks for 12 to 24 hours to dissolve the sticky mucilage. After fermentation, the beans are rinsed thoroughly and spread out to dry on patios or raised beds for several days, often with mechanical drying as a finish. Finally, a hulling machine removes the remaining parchment to reveal the green bean.

This method produces cleaner-tasting beans with brighter acidity and fewer defects. Around 70% of coffees from Colombia, Mexico, and Guatemala are processed this way. However, if fermentation isn’t carefully controlled, unwanted sour or fermented flavours can develop. When done right, though, it highlights each bean’s unique characteristics.

Natural Process

The natural or dry process is simpler and more traditional. Freshly picked cherries are spread out in the sun on large patios or raised beds for one to two weeks, or until they dry completely and make a cracking sound. The entire fruit—skin, pulp, and all—dries around the bean. Once dry, a machine removes the outer layers, including the dried pulp and parchment, to extract the green bean.

This method tends to produce beans with a heavier body, mild acidity, and a more rustic flavour profile. Most Brazilian coffees, along with many from Ethiopia and Yemen, are processed this way. However, natural processing is weather-dependent and more prone to contamination by defective or mouldy beans, so careful sorting is essential.

Shipping Raw Coffee Around the World

After processing, the green beans are packed into jute or burlap sacks and loaded into shipping containers. From remote highland farms to roasteries across the globe, these beans travel great distances before they ever see a roast drum. It’s a long journey—from tree to export, from mill to port, and eventually to your cup.

Frequently Asked Questions

How many coffee beans does one tree produce?

A single coffee tree yields approximately 3 to 5 kilograms of coffee cherries, which can be processed into about 0.6 to 1 kilogram of raw green coffee beans—around one-fifth of the cherry weight.

What’s the difference between Arabica and Robusta coffee beans?

Arabica beans make up about two-thirds of global coffee production. They are oval-shaped with a flat side, grown at moderate altitudes, and valued for their complex flavours and higher quality. Robusta beans are bitter, less acidic, and easier to grow at low altitudes with strong disease resistance, often used in blends or instant coffee.

What are flat beans and peaberry beans?

Flat beans are the standard coffee beans, formed when two seeds develop side-by-side in the cherry with a flat surface between them. Peaberry beans occur when only one round seed forms inside the cherry instead of two. They usually taste similar but may vary based on origin and processing more than shape.

What is the washed coffee process?

The washed or wet process involves removing the coffee cherry’s skin and pulp, fermenting the beans to dissolve the mucilage, then washing and drying them before hulling. This method results in cleaner, brighter flavoured beans and is used for most specialty coffee from countries like Colombia and Guatemala.

What is the natural coffee processing method?

The natural or dry process dries the whole coffee cherry in the sun before removing the outer layers. This produces beans with heavier body and more earthy flavours, and is common in Ethiopia, Yemen, and Brazil. It is more reliant on good weather and sorting to avoid defects.

Where do most Arabica and Robusta beans come from?

Arabica beans are grown mainly in high-altitude regions of Central and South America, East Africa, and parts of Asia. Robusta thrives in lowland, hotter, and more humid areas such as Vietnam, Brazil’s lower regions, and parts of Africa. Most Brazilian and Ethiopian coffees use either washed or natural processing methods depending on the region.

Recommended FrontStreet Beans for Exploring Green Coffee Origins

Try FrontStreet Coffee’s Ethiopia Yirgacheffe for a bright, floral washed Arabica with citrus and stone fruit notes—perfect for seeing how processing shapes flavour. For contrast, their Brazil Yellow Bourbon offers a classic natural-processed cup with nutty and chocolatey tones. Both highlight how origin and method define green bean profiles. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.