Before coffee reaches the roaster, it has already been shaped by a plant, a place and months of careful work. The country on the bag is only the beginning.
Understanding green coffee beans helps explain why two coffees can taste so different, even when they come from the same region. Origin, variety, moisture, altitude, density, soil and processing all contribute to the raw material that roasting transforms.
What are green coffee beans?
Green coffee beans are the unroasted seeds of the coffee fruit, commonly called a cherry. After harvesting, producers process and dry the coffee, then remove the remaining protective layers to prepare it for sorting, storage and roasting.
At this stage, the seeds are usually pale green, blue-green or yellowish. They do not yet smell like the coffee in your grinder. Roasting transforms their existing compounds and creates many of the aromas we recognise in a brewed cup.
Think of green coffee as flavour potential. The way it is grown and handled shapes that potential; roasting and brewing determine how we experience it.
1. How does origin affect coffee flavour?
Origin describes where a coffee was grown. That might mean a country, a region, a farm or a particular lot. Each level gives you a little more context about the coffee in your cup.
Country-level flavour descriptions are useful starting points. Brazil is often associated with chocolate and nuts, while Ethiopia is often associated with florals and fruit. But neither country has one fixed flavour. Different varieties, growing conditions and producer decisions can create very different coffees within the same origin.
When choosing a bag, look beyond the country name. A region, producer and processing method usually tell you more than a flag alone.
Explore our guide to coffee flavour by origin.
New to the term? Read what single origin coffee means.
2. Coffee varieties: the genetics behind the bean
Origin tells you where a coffee grew. Its genetics help explain which kind of plant produced it. To understand names such as Bourbon, Pacamara and Geisha, it helps to begin with the difference between a species and a variety.
Arabica vs Robusta: what is the difference?
Arabica and Robusta are the two main commercial types of coffee. Arabica belongs to the species Coffea arabica, while coffee sold as Robusta belongs to Coffea canephora. Each has its own genetic diversity and cultivated varieties.
Arabica is widely associated with aromatic complexity, noticeable acidity and flavours that can range from chocolate and nuts to fruit and flowers. It generally suits cooler growing conditions, which is one reason it is often cultivated at higher elevations in tropical regions.
Robusta generally suits warmer growing conditions and typically contains more caffeine than Arabica. In the cup, it is often associated with a fuller body and greater bitterness. It is used in many espresso blends and instant coffees, although carefully grown and processed Robusta can also produce distinctive, high-quality cups.
These are broad tendencies. Species alone cannot tell you how good a coffee will taste: variety, growing conditions, harvesting, processing and roasting all matter.
For the varieties below, the relationship is straightforward: Arabica is the species; Bourbon, Typica, Caturra, Maragogipe, Pacas, Pacamara and Geisha are varieties within it.
Explore World Coffee Research’s Robusta catalogue.
Coffee varietals and what they tell you
You will often see coffee varieties described as “varietals” on bags and menus. Understanding these names helps you look beyond origin and discover another reason why green coffee beans can develop different characteristics.
Variety influences the plant’s growth, productivity, disease susceptibility, bean size and flavour potential. Farmers choose varieties that suit their environment and livelihoods, as well as the quality they hope to achieve in the cup.
| Varietal | What it tells you |
|---|---|
| Bourbon | A historically important Arabica variety with excellent cup quality potential in suitable conditions. It is also the parent variety behind natural mutations such as Caturra and Pacas. |
| Typica | Another foundational Arabica variety, valued for its cup quality. It has contributed to many cultivated varieties, including the large-beaned Maragogipe. |
| Caturra | A natural mutation of Bourbon with a compact growth habit. Its smaller plant size allows closer planting; the name describes its genetics, rather than a particular flavour or roast style. |
| Maragogipe | Also written Maragogype. A natural mutation of Typica first identified in Brazil, with unusually large beans and leaves. Its impressive bean size does not automatically mean greater density or better flavour. |
| Pacas | A compact natural mutation of Bourbon discovered in El Salvador. Pacas is one of the two parent varieties used to create Pacamara. |
| Pacamara | A cross between Pacas and Maragogipe, developed in El Salvador. Recognised for its very large beans and exceptional cup quality potential, although characteristics can vary between plants and lots. |
| Geisha / Gesha | An Arabica variety with Ethiopian origins. The well-studied Panama Geisha lineage is celebrated for delicate floral, jasmine and peach-like aromas under suitable conditions. The name alone does not establish a coffee’s precise genetic identity. |
Is Geisha coffee Arabica?
Yes. Geisha, also commonly written Gesha, belongs to the Arabica species. Its distinctive reputation and flavour potential do not make it a separate species. World Coffee Research also notes that genetically different plants have been called Geisha, so a coffee’s producer and lineage provide useful context.
Does variety determine coffee flavour?
Variety shapes flavour potential, but it cannot guarantee a particular taste. The same variety can express itself differently depending on climate, altitude, soil, processing, roasting and brewing. A familiar name is a useful starting point; the individual lot’s tasting notes help you decide what to expect.
Bean size needs the same care. Pacamara and Maragogipe are known for large beans, but size and density are different measurements. Bigger beans are not automatically better beans.
For an example from our collection, explore our Colombia Finca Monterverde Geisha Red Honey, where variety, growing conditions and processing come together in one coffee.
Further reading: World Coffee Research’s Arabica varieties catalogue, including its profiles of Pacamara, Maragogipe and Geisha.
3. Why moisture content matters in green coffee
Green coffee is dried before shipping, but it still contains water. Moisture content describes how much of the bean’s mass is water, usually expressed as a percentage. A reading of 11% means approximately 11 grams of water in a 100-gram sample.
Commercially prepared green coffee commonly sits around 10–12% moisture. Treat that as a useful guide, rather than a universal quality score: the lot, measurement method and agreed specification matter.
Drying and storage help preserve the coffee until roasting. Excess moisture and unsuitable storage can encourage deterioration; excessive or uneven drying can also compromise quality. A moisture reading alone cannot tell you whether a coffee has been handled well.
Moisture content and water activity are different
Moisture content measures the amount of water. Water activity describes how available that water is for microbial growth and other changes. Two coffees with similar moisture percentages can have different water activity readings.
Research: Cafe Imports — water activity in specialty green coffee.
For a roaster, moisture is also part of understanding how a lot behaves under heat. For a coffee drinker, the practical point is simpler: careful drying, protective packaging and good storage help the coffee arrive in a condition that can fulfil its potential.
4. Altitude and density: useful clues, not quality scores
Altitude is usually listed in metres above sea level, or masl. Higher elevations often bring cooler temperatures and slower fruit maturation, which can influence bean development and cup character. However, temperature, shade, latitude and variety also matter. A farm at 1,500 masl near the equator does not necessarily share the climate of a farm at the same elevation much farther south.
World Coffee Research explains how optimal altitude changes with latitude.
Density describes mass relative to volume. It is related to a bean’s physical structure and moisture, and is different from bean size. A larger bean is not automatically denser. Bulk density measurements also include the spaces between beans, so measurement methods matter.
Slower maturation is often associated with denser coffee, but altitude cannot substitute for measuring a lot. Roasters consider density alongside moisture, bean size and sample-roast results when deciding how to apply heat. “Higher” and “denser” are useful information, not automatic reasons to prefer one coffee.
5. Terroir and soil: how the growing environment matters
Terroir describes the growing environment: climate, soil, terrain, water and exposure. These factors interact with the coffee variety and the way the farm is managed.
Soil supports roots and supplies water and nutrients. Its pH, organic matter, drainage and nutrient balance affect plant health and fruit development. Research finds that environmental and nutrient-management effects on coffee chemistry and sensory quality are complex, with results varying between studies.
Research: environmental conditions, nutrient management and coffee quality.
A useful distinction: soil composition is not a tasting-note recipe. “Volcanic soil” does not guarantee a superior cup, and a mineral in the ground does not translate directly into a matching flavour. To judge the coffee, we still need to taste it.
This is why detailed farm information is interesting. It helps explain the conditions behind the coffee while leaving room for the skill of the producer and the character of the individual harvest.
6. Coffee processing methods: what happens after picking?
Processing is how producers handle the harvested cherry and prepare its seeds for drying and milling. The amount of fruit left around the seed, fermentation conditions and drying approach can all affect the finished coffee.
| Method | What happens | Possible cup character |
|---|---|---|
| Washed | Skin and pulp are removed, then mucilage is removed through fermentation and washing, mechanical removal, or a combination, before drying in parchment. | Often distinct flavours and a clear expression of acidity. |
| Natural | Coffee is dried inside the whole cherry before the dried fruit layers are removed. | Often fruit-forward, with a rounded or fuller impression. |
| Honey / pulped natural | The skin and some fruit are removed, while some mucilage remains during drying. Terminology varies by producer. | Can combine fruit character, sweetness and texture. |
| Wet-hulled | Parchment is removed while the coffee is still relatively moist, followed by further drying. | Often associated with weighty, herbal or earthy profiles; clean and varied expressions also exist. |
These are tendencies, not guarantees. Every method can produce excellent coffee, and every method depends on careful execution. “Honey” refers to sticky fruit mucilage; it does not mean honey has been added. Colour terms such as red or black honey are not a universal grading system.
Further reading: Cafe Imports — coffee processing methods.
Where do anaerobic fermentation and carbonic maceration fit?
These terms describe fermentation approaches, rather than a completely separate replacement for washed, natural or honey processing. A coffee can undergo an oxygen-limited fermentation stage and then be dried as a natural or finished as a washed coffee.
Anaerobic processing generally refers to fermentation under oxygen-limited conditions. Carbonic maceration commonly involves whole cherries in a carbon-dioxide-rich environment. Producer protocols vary, so the name alone does not tell you the full sequence or predict the flavour.
The same applies to descriptions such as “lactic” or “yeast fermentation”: ask what was controlled or introduced, and how the coffee was subsequently dried. More processing steps do not automatically mean better coffee.
Our Flora Fruto Tasting Box makes this topic easier to explore: coffees from the same farm, with different fermentation approaches. It is a practical tasting comparison, rather than proof that every other variable is identical.
Explore the Flora Fruto Tasting Box.
Putting it together: how to read a coffee label
Take our Colombia Finca Monterverde Geisha Red Honey as an example. Each detail answers a different question:
| Label detail | What you learn |
|---|---|
| Colombia; Herrera, Tolima | The country and region where the coffee was grown. |
| Finca Monterverde; Gutierrez family | The farm and producer information. |
| Geisha / Gesha | The Arabica variety reported for this coffee. |
| Approximately 1,900 masl | The growing elevation, which gives context about its environment. |
| Red Honey | The processing description: mucilage remains on the seed during drying. |
Our tasting notes describe jasmine, red fruit and Fuji apple sweetness. Those notes describe the finished cup; they are not separate flavours that can be assigned neatly to the soil, altitude or variety.