We hope you’ve read our first post, A Brief History of Coffee, and if you didn’t we suggest you do, coffee’s history is rather rich. We finished with the facts that coffee is the third most popular beverage in the world and the planets second most traded commodity! But how does it get from the plants on the hills in Central America, Africa, the Middle East or Indonesia to your favourite coffeehouse and into your cup?
Firstly we must mention that coffee can only be grown in the tropics. This is the region surrounding the equator found between the Tropic of Cancer in the Northern Hemisphere and the Tropic of Capricorn in the South. All of the coffee in the world comes from this region and then makes it’s way to cups all over the world. So let us see how it does it.
Coffee beans are actually the seeds of the coffee plant (genus Coffea). There are several varieties of Coffea plant but the two we drink the most are Coffea Arabica, responsible for around 75% of coffee consumed worldwide, and Coffea Canephora, more commonly known as Robusta, is responsible for approximately 25%.
Seeds are normally germinated in nurseries and spend their first six seedling months being watered frequently and shaded from strong sunlight. These seedlings are much more fragile than older plants and only once they are hardy enough to be permanently planted will they be moved to the fields.
Once planted the coffee tree take 3-4 years to grow to maturity and begin fruiting. The coffee cherries (each containing two seeds) start off green and are ready to be harvested when they are a bright, deep red. Coffee can be harvested in two ways, either by machine or hand-picking. The second is obviously the most labour intensive and costly and is therefore mainly used to harvest the finer Arabica beans. After being harvested the beans are taken to the processing plant.
This process must begin as soon as possible after the picking of the fruit so that it doesn’t spoil. For this reason, amongst others, the processing plants are almost always located on the same site as the coffee farm. There are two methods to processing coffee beans:
The Dry Method: The oldest and simplest method of processing coffee beans, this is usually used in countries where water is a scarce resource. The fresh cherries are spread out on a large surface to dry in the sun, getting raked regularly to turn them over. They are covered at night and during the rain until the moisture content of the cherries drops to 11%. This usually takes around 4 weeks.
The Wet Method: This method removes the pulp from the fruit leaving only the parchment skin on the seed at the end. This method requires lots of machinery and, as the name dictates, lots of water. First, the beans are fed through a pulping machine to separate the skin and the pulp from the beans. After this, the beans are immersed in water where the heavier, ripe beans sink to the bottom and all the non-ripe and bad beans float to the top and are skimmed off and discarded. The beans then head into large water-filled fermentation tanks. Here they will sit until the layer of mucilage (think mucous and you’ve got it) is dissolved by naturally occurring enzymes (anyone remember our Breaking Down Beer article). After this the wet beans still need to be dried, this can be done by either laying them out in the same way that is done in the Dry Method of processing beans or it can be sped up by putting the beans through massive drying tumblers.
Milling and Sorting
Both of the above processes leave a dried skin stuck to our precious coffee beans, which needs to be removed in order for them to be roasted. Once the beans have been processed they’ll be milled and sorted in order to prepare them for exportation.
All the beans go through a hulling machine which removes any of the husks that are still left on the beans. Beans from the Dry Method of processing will have the whole dried husk needing to be removed whilst beans from the Wet Method will have a thin skin called parchment; these beans are referred to as parchment coffee. Sometime the beans will also go through a polishing process to remove any small slivers of skin remaining. Although this doesn’t really make a difference to the end product many people consider polished beans to be of a higher quality than their unpolished counterparts.
After all this the beans are graded and sorted. This usually done by machine at first and finally by hand in order to ensure only the highest quality product makes it out of the door. Beans are sorted by size by being passed through a series of screens.
Tasting before Exportation
This is where the first beans get their roasting, but only a small amount of them. Coffee has to be tasted to ascertain the quality of the bean and therefore how much it can be sold for. The Tasters are called Cuppers and the experts can taste tens if not hundreds of types of coffee a day.
The beans are first looked over for aesthetic quality before being roasted in a small batch and immediately submerged in water with a carefully controlled temperature. From here tasting coffee is very similar to wine tasting: you take a good nose of it to see how it smells, the coffee is then rested for a few minutes before being “nosed” (sniffed) again. Next, the cupper takes a small sip from a spoon, inhaling as he/she does so in order to spread the coffee all around the mouth. They then weigh it on the tongue and spit it out. That’s why it’s not like beer tasting, we don’t spit out beer!
They aren’t just tasting coffee beans to assess their quality but also to see which ones can be blended and which roasting temperature is perfect for the different beans.
The milled, sorted, graded and tasted beans are packaged into traditional sacks, and are now called green beans and are all ready to be shipped out and roasted en mass.
Roasting turns that green coffee bean in a beautifully aromatic coffee bean used to make your morning espresso. Beans are usually roasted in the country they are imported into because the more freshly roasted the bean the more flavourful the final cup of coffee.
Roasting usually takes place at about 285ºC and the beans are kept moving, usually by circulating air through the roaster. This stops them from burning and helps to ensure an even roast.
Beans can come out of the roaster at different times depending on how dark and strong you want your roast. After roasting the beans are cooled and are ready to go into the grinder.
Different brewing methods require different grades of grind (between fine and coarse) and it all depends on how long the grounds will be in contact with water. As a rule of thumb, the finer the grind the less time the coffee spends in contact with the water. So espressos require one of the finest grinds whilst those in your french press require a much coarser grind to bring out the right flavours.
The final part of the process before the drinking is the brewing. There are many different methods and each can bring out different results from the same beans. It all depends on what your preference is. We’ll discuss different brewing process in a later article. For now, sit back and appreciate the rest of that coffee, because, even though they’re not actually in the cup, those beans have been through a lot.
Image Credit: Public Domain Images: PIXNIO