With our blog this month we wanted to take you behind the scenes to learn more about the different stages that our coffee goes through at source, before making its way over to us for roasting!
Coffee pickers can pick up to 90 kilos of coffee cherries per day, and only 20 percent of this weight is the actual coffee bean! So if they picked the maximum of 90 kilos that would be about 18 kilos of green beans per day, which works out around 1.8 kilos of beans an hour. Full coffee sacks weigh anywhere between 60-70 kilos… so as you can see, it's a pretty full on day!
Our coffee is selectively picked - which is when the coffee pickers only harvest the reddest, ripest cherries which have the most flavour. This will require multiple visits to the same plant over the course of weeks. It’s labour intensive but it also means the best quality cherries are selected and the farmer will receive the best price for the crop. Many of the farms we work with incentify their pickers and pay them a bonus for picking only the very best!
From one labour of love to the next. Once coffee cherries are picked they need to be processed quickly to stop them from spoiling.
Natural or Dry Processing - The oldest form of coffee processing. Coffee cherries are placed on either a drying patio or raised beds for a number of weeks and are raked over a few times a day to allow even drying and prevent spoiling. The heat and dry air causes the cherry to dry out (think grape into a raisin) until it has a moisture content of between 10-13%. Once this rate is reached the coffee is then taken to the mill to be hulled. This works best in countries with low rainfall, low humidity and of course some warmth. You’ll find this practise most common in places with low access to water.
Natural coffees tend to have more intense fruit notes, higher sweetness and a fuller body.
Washed Process - After picking, the coffee passes through a pulper which removes the flesh of the cherry and pops the seed out. Some mucilage will remain on the coffee bean which needs to be removed - this can be done in a couple of ways. One way is by using fermentation tanks in which bacteria will break down the mucilage. Another way is mechanically, in which stiff brushes run over the coffee bean and physically pull any mucilage off - although this is not as effective as fermentation it does save water.
After washing the coffee needs to be dried. This can be done with drying patio, raised beds, parabolic dryers or mechanical drying. The coffee needs to be turned regularly throughout the day to stop any spoilage and allow even drying to the desired 10-13% moisture level.
Washed coffees tend to be cleaner in flavour with more floral notes, higher acidity and are a truer representation of the coffee bean itself.
Honey Process - When the coffee is picked, most of the fruit is removed leaving some mucilage (think about when you eat an olive and can’t get all of the fruit off the stone), it then goes through a similar process to a natural and is dried. There are varying levels of drying time (dependent on sun/heat exposure) which are termed Yellow, Red or Black honey processing.
These coffees are quite complex and give a nice balance (if done well) of washed and natural processing.
Before being exported the coffee bean needs to have its parchment layer removed. The parchment is a thin protective layer over the green bean that stays protected throughout the entire processing time, but does need to be removed before shipping.
Sorting & Grading
Yet another labour of love. Coffee beans can be sorted by size and weight. When done by weight, jets of air are used to sort lighter beans from heavier ones. Sorting beans by size is done via screen sizes, which is normally between the sizes of 10-20. The number represents the size of a round hole's diameter in terms of 1/64's of an inch. A number 10 bean would be the approximate size of a hole in a diameter of 10/64 of an inch.
After being seperated by size or weight the coffee lot needs to have any defects removed. This is mostly done by hand but on larger farms can be done by machines. They will remove any beans that are badly hulled, an unacceptable size or colour, bug damaged or over fermented.
Each stage that the coffee bean goes through helps to add to the overall quality of the beans and will have a massive impact on the final roasted product. When deciding on a roast profile for a particular coffee ourselves, we will take each stage of processing into account, ensuring that we showcase the coffee at its very best and pay respect to everyone involved in the farming process.