Bean there, bean here – the journey of coffee4th Sep 2018
We seldom stop to think about all the processes necessary to ensure that we get to wake up with a delicious and reviving cup of coffee every morning. But it’s quite a trip.
Somewhere in the tropical regions of the world – perhaps, like the ABBA song, ‘high-igh-igh on a mountain in Mexico’ – lives a young coffee farmer. Let’s call him Angelo. Angelo may be a wealthy landowner with thousands of hectares planted to coffee, but it’s far more ABBA-ly romantic to think of him as a peasant farmer with about 20 trees.
Coffee trees grow in a wide belt of tropical and subtropical countries on every continent except Antarctica and Europe. The best coffee is grown in mountainside forests or mixed plantations – taking advantage of the long tropical days, but with the temperature mitigated by the high altitude and dappled shade of natural forest trees or interplanted fruit trees. This produces the best coffee, but not in the most efficient way. For efficiency and profit over quality, Angelo’s counterparts will clear the forests and plant vast hectares of monoculture coffee. Under these conditions, and at lower altitudes, the fine arabica coffee trees wilt and sicken, but the aptly named robusta trees thrive.
Angelo and other small-scale farmers inspect their few trees every couple of days, and hand-pick only the ripest cherries, carefully leaving the not-so-ripe ones for later. That’s a romantic notion, and it does happen, but very infrequently. At the other end of the scale, huge coffee estates send in ginormous mechanical harvesters when most of the cherries are ripe, not too many are overripe or downright rotten, and quite a few are still green. And there is a whole spectrum in between in which the coffee is hand-harvested by more or less dedicated or disinterested paid seasonal or permanent workers.
The heart of the matter
In the long, long distant past, the coffee cherry (or berry) was harvested for its flavour and juice, and the seed discarded. But those days are over, and now – as a rule – it’s the cherry that gets discarded. There are various methods of separating the seed and the fruit, with each method producing a different flavour profile.
Coffea is a very unusual fruit. Whereas most fruits have a skin, pulp and a seed, coffee has five layers: the outer skin, the pulp, the mucilage, the parchment and – the treasure at the heart – the seed, which we call a bean. There are three stages in getting to this flavourful heart – processing, drying and milling – and each stage can be carried out in a number of ways. In some countries, the initial quality assessment will happen during processing.
The first step is breaking down the pulp so that it can easily be removed from the pip. There are basically four methods.
- The original method was the dry process, which is basically spreading the cherries out in the sun until they shrivel up.
- The wet process, which is also called fully washed, involves removing the pulp first, then full immersion and soaking of the remaining mucilage, letting it ferment and separate from the last two inner layers. The wet process results in a cleanertasting coffee, but it requires a lot of water.
- The pulp-natural or honey process has become more popular recently. Even though it has nothing to do with
honey, it produces sweeter coffee. In this process, the skin of the cherry is removed, and the pulp then dried in the sun allowing it to get sticky – like honey.
- You can also break down the pulp by fermentation, which can be initiated by either adding a substance such yeast or CO2, as in winemaking, or by the application of a combination of heat, moisture and pressure.
- Less common methods include monsoon processing and biological processing. Monsoon processing happened pretty much by accident because, in the early days of sail, coffee cherries harvested in Asia had to wait out the monsoon season before they could be transported. So, they would be stored in huge, open-sided warehouses, where they would swell and ferment. Biological processing was also a serendipitous discovery, but it has recently become somewhat controversial. It is accomplished by wild (or domestic) animals eating the yummy cherries, digesting them, and ‘discarding’ the seeds. The perfectly processed seeds are then picked out of the scat. This produces a great coffee – but for one very important reason. The animals are choosy, and they pick only the best, ripest cherries to munch so they pre-select the finest coffee. Since the movie The Bucket List, one biologically processed coffee – kopi luwak – has become extremely popular and very expensive. So, enterprising – and not too scrupulous – farmers are imprisoning hundreds of civets in tiny cages and feeding them haphazardly harvested coffee cherries, and selling the resulting s**t as high-priced kopi luwak. Angelo is more likely to process his coffee by the dry or fully washed method.
Once the bean has been separated from the cherry, it has to be dried. There are three methods. Patio drying is simply spreading the beans on a cement or clay floor and allowing them to dry in the sun, regularly raking them to prevent clumping. A similar method, known as African raised bed drying, involves laying the beans out on raised beds of some kind of mesh, and also turning them regularly. One advantage of this method is that it takes up less space, as the beds can be stacked like bunk beds.
An enhancement of this method, which is used in very rainy regions, involves covering the beds with a huge roof and sides that can be lowered for rain protection, or raised to allow airflow. These structures are called parabolic dryers, and they’re not very high tech, so it’s quite likely that Angelo will have built one in his back yard. For both these methods, drying takes between two and four weeks. Large-scale coffee producers tend to machine dry their beans in huge contraptions that look very much like giant tumble dryers – a process that is completed in 24 to 48 hours.
Selling and storage
Angelo is lucky that he lives in Mexico, where there are companies dedicated to sourcing speciality grade coffee. So, he can take his carefully nurtured and processed beans for assessment. If the beans have zero major defects, and an acceptable minimum minor defects, they will go through a secondary process of roasting, cupping and scoring for taste. If Angelo’s beans score 80 or more according to the Speciality Coffee Association (SCA) cupping score sheet, they will qualify as speciality grade coffee, and will fetch a premium price. As Angelo heads home, smiling,
with his donkey, Dapple, the beans will be milled, sorted and graded.
Unfortunately, this system is not as efficient in every coffee growing country in the world and, in some cases, the grading takes place later – often after the coffee has been sold to a co-op or a government board – so the farmer is not directly rewarded. But this is changing, and the move towards conscious consumerism has increased the demand for speciality grade coffee with a verified chain of custody and provenance.
Milling, sorting and size grading
After the lot has been sold, the dried and denatured cherry is milled to remove any remaining pulp and the parchment, and the beans are pre-sorted using a gravity bed and screens. They will then be further sorted either visually or by an optical sorter, and graded according to size and defect – or lack thereof.
Then they get packaged and transported to the purchaser, who – in the case of Angelo’s speciality grade beans – will be a speciality coffee roaster or distributor. This special coffee will then be sold in smaller lots to speciality artisanal roasters who will lovingly bring out the best quality of the beans, and will sell them freshly roasted to a small, discerning market – people who can taste the difference between Angelo’s tenderly nurtured coffee and the somewhat less gently produced mass-market coffee. They will take the coffee home, carefully grind it just before
brewing it using their current favourite method, and savour every sip.
And Angelo, high on a mountain in Mexico, will be lovingly tending his coffee trees – as will his many counterparts in Africa, Asia and South America. Speciality coffee is a growing trend.