Understanding green coffee: from seed to bean (part 1)

We are Sample Coffee Roasters - we not only serve but also roast our own coffee!

Before becoming roasters, all we had to do is pick and buy our favourite finished product from other local companies (just as restaurants do with wine or beer). Now, there are some added layers of complexity to our day-to-day business, but this allows us to “design” each coffee just the way we want them.

In this journal “series” we explain in a short and straight fashion the basics of the green (unroasted) coffee journey, from the tree to our warehouse.


There are two main coffee plant species that you may be familiar with: Arabica (Coffea Arabica) and Robusta (Coffea Canephora). They both produce coffee fruit or cherries, but their properties and behaviour are different. For example, Arabica grows in higher altitudes and needs stricter care, but provides more flavourful beans. Robusta can grow in lower elevations and is more resistant to diseases, but its taste can be duller, and it carries double the caffeine than the first.

From each species, there exist many crossings, hybrids and mutations of the original varieties (or sometimes referred as varietals). Human intervention played a huge role in its global development. The first coffee plants originated in the south-west region of Ethiopia. Being in its natural environment, thousands of native varieties grew and evolved in the forests of this high and humid region.

After the XV century - and following the swing of politics, science and colonization - coffee spread first to the Arabian Peninsula and then to the rest of the world. Each plant would either adapt to the very different environments or, instead, humans would modify their genetics to grow and produce as they wished.

For example, Caturra is a variety evolving from the Bourbon, which is at the same time a variety of the all-time original Arabica Typica.


The coffee you drink grows in two of these ways:

Naturally occurring in forests:

Most of our Ethiopian coffees are forest-grown; they come from the region where the original species lived and spread. The coffee cherries grow in rather tall “trees” under a mix of other canopy trees, and the producers (in this case gatherers) pick them as they ripen.

Coffee farms (plantations):

Most of the coffees coming from other regions of the world grow in coffee plantations. The farmer or business owner generally choose the plant species and variety they think best for their enterprise, transforming the land and conditions to carry on with this agricultural production.


Either from forests or farms, the cherries are picked when they are ripe (juicy red) and from this point on the “processing” stage begins. The main methods are:


This process completely separates and discards the pulp, keeping only the coffee bean. The cherry flesh is removed mechanically, isolating the bean which is submerged in water and let ferment for several hours. After this period, it is rewashed with clean water and then air/sun-dried in “beds”. The technology for this process varies immensely from farm to farm due to access to resources, funds, knowledge and technology. And it requires access to power generation and quite a lot of water.

Most of our coffees are processed using this method, as it highlights the properties of the bean and, when done well, this process tends to result in more distinct, cleaner flavours. Some of our favourites have been the Marawaka (PNG), Maria Edilma Medina (Colombia) or Mbrizi (Burundi).


The whole cherry (flesh + bean) is left as it comes and air/sun-dried in beds right after picking - no separation of layers is done as opposed to the washed method. This process is typically performed in regions with no real access to technology or water, or when the gatherers/farmers live too far from a washing station. This independence from electricity and water makes this method the one with the least impact on the environment.

Achieving consistency of flavour is somewhat tricky because it requires the best practices and full attention from the producers as the cherries ripen and ferment. It requires less technology but the right climate conditions and extreme care and experience. The flavours are quite complex and fermenty, often showing jammy fruit and a little winey-ness.

You can tell we are quite picky with our naturals, as we’ve only purchased two single origins so far. Also, our discontinued Toucan Party blend featured washed and natural process coffees. Our highlight: Limoncillo from Nicaragua.

Honey/Pulped Natural: 

The name comes from the stickiness of the beans during this process. It’s somehow in between a washed and dried/natural process. Some flesh or pulp is left on the cherry as it goes through the de-pulping machine, straight after picking. The fermentation occurs right after when the beans are left drying either in indoors or outdoor beds. (This video from Cafe Imports explains it really well!).

This tends to highlight sweetness and fruitiness (less exaggerated than in the naturals) and a more rounded acidity than washed coffees. We just had one of our only honey process ever coming from Sehe (Burundi).

We hope this throws some clarity on some of the coffee basics and helps you understand the core differences between the coffees on our shelves. Coming up next: the complex journey of coffee - from forest to warehouse.

Thanks to Cafe Imports for all the origin photos!

If you are interested in expanding your coffee biology knowledge, we fully recommend watching this video where Counter Culture develops on the coffee plant genetics and expansion around the world.



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