Each stage of coffee production, from growing through to brewing, requires different expertise and technical know-how.
For roasters aiming to produce the perfect blend, among the most vital of these stages is selecting the right ‘green’ beans at the origin.
Green beans are the stones of the fruit, or ‘cherry’ of the coffee plant, which have been processed, dried, and hulled. They have a grassy smell and taste, and so bear little resemblance to the delicious nut-brown beans they will become once roasted.
However skilful and well-honed the roasting process, a low-quality or unsuitable batch of green beans will never produce the flavour profiles required to make a quality coffee.
That’s why these complex and crucial judgements at the origin require as much care as possible.
Initial checks can be done quickly by sight, smell, and touch.
Unroasted beans should feel dry and smooth; if they are too soft then they haven’t been dried thoroughly enough and will go mouldy in transit or storage.
Green beans should smell pleasantly of grass, not alcohol, which is an indication of unwanted fermentation.
Green beans do vary in colour, but, as the name suggests, the most desirable tend to be a creamy green colour, and uniformity here is a good indicator of quality.
Sophisticated colour-assessment technology is available that can measure colour uniformity far more accurately than the naked eye.
Several samples are then taken at random from the same harvest to find the ratio of sub-par beans, known as ‘defects’.
Insect-damaged, unripe, split or otherwise blemished beans can all taste unpleasant when roasted, infecting the batch with bitter, woody, or papery flavours.
Size also matters as differently-sized beans are impossible to roast together evenly. Small, underdeveloped beans are less dense than their larger cousins and will be over-roasted by the point at which the rest of the batch is ready.
Batches that have a high percentage of defects will be rejected, even if the good beans within it are exactly what the roaster is looking for.
Uniformity is an indication that the growing season and harvest have gone well.
Once these initial checks have been done, buyers will ‘cup’ the coffee. Cupping is a standardised brewing procedure that allows buyers to assess a coffee’s flavour characteristics.
Most use a uniform set of criteria and points system to grade the coffee, which will have been lightly or ‘sample’ roasted for this process. Although the aim is to make cupping as repeatable and universal as possible, it takes exceptional skill and experience to cup coffee accurately.
Through cupping, buyers are looking to determine both consistency and flavour profile.
As coffee-growing seasons vary in different parts of the world, selecting green beans is a constant undertaking.
Many buyers engage with growers and importers constantly to keep up-to-date with challenges, weather conditions, and other factors that can affect the harvest.
Even coffee from a trusted producer needs to be rigorously checked to make sure this year’s as good as the last.
Maintaining relationships with coffee producers
At Caffe Nero, we’re proud that we buy our coffee from producers that we know.
This model has many advantages for everyone involved. Stronger relationships with our growers mean that we can increase our knowledge of the coffee we buy, and even influence how it is produced.
This way, we can maximise the chances our beans, and ultimately the coffee in your cup, will be precisely how we want it.