Not So Natural Coffee

As coffee roasters we have I believe an enormous responsibility to our producers to deliver the distinctive flavours of every origin that crosses our path. We can take a view as to the style of roast that we think is most appropriate, light, medium or dark. That though tends to reflect the preferences of the consumer our customer rather than the desires of the origin. This approach isn’t necessarily wrong. Too many times “speciality” roasters forget about the demands of their customers in their unerring desire to draw out the “citrus” notes or “wild melon” flavours and then wonder why these coffees aren’t selling.

Coffee is incredibly complex at the best of times, not just because of where it is grown, but also because different origins will process their coffee using different methods. That difference will always end up in the cup in some form or other and makes things really interesting.

So time for a quick lesson on what needs to happen to the coffee cherry once it has ripened and  been picked. To get to the green coffee bean that is eventually roasted and ground the following needs to happen.

The outer skin and pulp has to be removed. This leaves you with the sticky mucilage and parchment layer that needs to be removed before finally you are left with the green coffee bean. However what you leave and what you take away will vary depending upon the taste profile the producer is looking for or it could be tradition. For example in Sumatra there is a process called wet hulling which isn’t found in other parts of the world. Finally it could be the processing type is affected by the volume of water available.

If you are now completely confused I hope the following explanation will clarify that last paragraph!

Natural process –

Here the outer skin and pulp are left on the coffee bean and are either dried naturally (in the sun) or can be mechanically dried. I experienced mechanical drying on the Wahanna estate in Sumatra, it’s quite a soothing sound as if the tide were washing the sea shore as the giant driers churn the coffee cherries. The result is that all the fruit flavours from the pulp get into the green coffee and although the outer dried pulp and parchment are hulled off, the fruity / winey flavours are quite discernible in the cup. Particularly when using a filter method.

Washed process –

This process delivers a much cleaner cup. The pulp is removed using a pulping machine. The parchment coffee is then placed in large vats of water for a few hours, this removes the sticky mucilage. The parchment coffee is then dried and finally hulled and sorted. The result is a much cleaner tasting coffee and usually results in a pleasant light caramel taste in the cup.

Inevitably there is a process that sits in the middle of the above two processes, namely Honey process.

Honey process –

Here the pulp of the cherry is removed but now rather than washing off the mucilage the coffee parchment is dried and finally hulled. The resultant drink will have more fruity notes as the mucilage will have soaked into the green coffee but will not be quite as distinctive as if the coffee were naturally processed.

Today origins are experimenting with many different process methods which means that you can have coffee from a single estate processed using three different methods each of which will deliver a different taste profile.

So next time you’re buying coffee look out for “process type” on the label, it’ll help to explain why that coffee has certain notes that maybe others don’t have.