Warning: after this, you might never look at your coffee the same way again.
What happens to coffee after it has been picked, processed, dried, and rested?
Before green coffee begins its journey to Europe, it has one more important stop: the dry mill.
This is where coffee gets its final preparation before export. Behind the scenes, a whole series of machine and, most importantly, people-work together to clean, sort, and prepare the beans for their journey.
Inside the dry mill
The dry mill is a busy place. Different machines perform different jobs, each helping to improve the consistency and quality of the final lot.
The huller
The huller removes the parchment surrounding the coffee bean, preparing it for the next stages of processing and sorting.
The destoner
Think of the destoner as the coffee’s security guard. It helps remove stones and other foreign materials that may have made their way into the coffee during harvesting and processing.
The screen size machine
Coffee beans are sorted according to size using screens.
You will often hear that screen size 16 is the gold standard, but there is a little more to the story. Some of the most beautiful coffees, particularly those grown at high altitudes, can produce smaller beans that are incredibly dense and full of flavour.
Bigger doesn’t automatically mean better.
The density sorter
Density sorting helps separate lower-density beans from denser ones and can help reduce defects such as quakers.
But there is an important distinction: these machines reduce defects; they don’t magically eliminate every single one.
The color sorter
Finally, the color sorter uses optical technology to identify and remove beans with visual defects, such as black or sour beans and other unwanted variations.
Every machine has a role to play. But none of them is a magic wand.
They are tools that help people improve the quality and consistency of coffee, but coffee is a natural agricultural product, and neither machines nor humans are perfect.
Does this mean your coffee is completely defect-free?
Nope. And that’s an important part of understanding specialty coffee.
Dry milling helps reduce defects and prepare coffee for export, but it cannot guarantee that every single bean will be perfect.
The people working at the mill carefully monitor the process and do their best to deliver the highest-quality coffee possible. Still, there will always be some natural variation.
A little understanding goes a long way.
The surprising amount of coffee that never reaches the export bag
Step outside the dry mill and you’ll quickly notice something else: parchment. Lots and lots of parchment.
Parchment is one of the many byproducts created during coffee processing. And it is a good reminder of just how much happens before that small green bean reaches your cup.
Here’s a number worth thinking about.
Starting with 100 kg of coffee cherries, after processing, drying, milling, and sorting, you may end up with only around 16 kg of exportable specialty-grade green coffee.
That’s a lot of coffee that doesn’t make it into an export bag.
So the next time you enjoy a cup, remember that coffee isn’t made in a factory with the push of a button. It is the result of nature, careful processing, machinery, quality control, and the work of many people along the way.
And what happens to all that parchment?
It doesn’t necessarily go to waste.
Coffee parchment can have a useful second life, depending on the farm and mill.
Compost: Packed with organic material, parchment can be returned to the soil and become part of another growing cycle.
Fuel: Some mills using Guardiola dryers can reuse parchment as a source of energy.
Chicken bedding: At the farm we visited, parchment gets another job entirely, as bedding for the chickens.
Even after helping us get coffee, it keeps working.
From the dry mill to the container
Once the coffee has been processed, sorted, and prepared for export, there are still a few steps before it actually leaves the country.
Eventually, the bags are carefully stacked and packed into the container by the people who make the whole process happen.
Then comes the moment we’ve been waiting for.
The container is locked, and the coffee is ready for its next adventure.
Well… almost.
The long road to the port
We’d love to say that we followed the truck all the way to the port, but sadly, we didn’t.
Although, believe me, sometimes we really want to!
This particular coffee had around 10 hours of travel ahead of it, making its way to Puerto Barrios, Guatemala.
Once there, it was loaded onto a ship and began its journey across the ocean towards Europe.
And that’s the part of coffee sourcing we love the most: being able to experience the journey from origin all the way to the final cup.
It’s easy to forget how much happens before that first sip.
We get to visit the farms, meet the people behind the coffee, see the processing, walk through the dry mills, follow the logistics, and watch the coffee slowly make its way towards you.
By the time it reaches your roastery, it has already travelled a very long way.
And knowing that journey makes every cup taste just a little bit different.
The story has been brought to you by Jola, co-founder and green coffee buyer at 88 Graines
