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Bean to cup journey by Bewley's (the Cafe2U coffee roaster) Part 2

Tuesday, June 28, 2016

Sorting & Grading 
Cherries are dropped into water channels where mature cherries sink and immature, less dense cherries stay at the surface. These ‘floaters’ are separated.
After drying, coffee is typically sorted by screen sizing & density and then other levels of sorting can be applied.
Electronic optical colour sorting, a high speed camera matches colour of green coffee and ejects irregular beans. In some cases, UV light optical sorting is also applied to detect phenolic and other defects. 
Finally, workers may spend many hours manually sorting chipped, broken of irregular beans.
The physical area i.e. a single plot, ‘micro farm’ or tablon. This can include general selections by altitude such as ‘SHB/SHG - strictly hard Bean or strictly high grown.
By size: Screen number – for example 14/15  or 17/18, AA, AB or name ‘Excelso’ or ‘Supremo’.
The coffee on a farm can be separated by numerous variables into ‘micro-lots’, special picks or selections. Common micro-lot separations included:
- Small plots of land;
- By plant varietal: Such as Typica, Bourbon, Caturra, Catuai etc.
- By process; Washed through to natural with many variations in between.


Processing is simply the removal of the cherry fruit/flesh from the underlying seed. There are 3 main process, although many variation on each:
- Natural/Dry Process: Coffee dried in the cherry for longer periods, often picking up fruit tastes and sweetness of the coffee fruit, but can lead to over-fermented tastes or dirty flavours if done incorrectly; 

- Washed/Wet Process: Coffee immediately de-pulped then any remaining fruit (mucilage) is either ‘scrubbed’ mechanically or more commonly loosened over a period of 12-24 hours via a process of controlled fermentation. Coffee then washed and dried in parchment before milling.

- Semi-Washed/Honey/pulped natural: A hybrid method, where only the skins, but not all mucilage (Sp: miel or honey) removed from the cherry. Coffee then left to dry similarly to washed coffee. Various levels of mucilage can be left on, and along with frequency of turning, depth of coffee on drying bed and numreours other factour can influence the character and classification of yellow, red, black or any other name for the honey process.

Once dried down to 11-12%, the coffee still in parchment is left in repository for a few weeks to even out moisture and ‘rest’.
From there it will go the dry mill to have the parchment or ‘pergamino’ removed and be bagged (or vac packed) for shipping.
Shipping is typically containerised, with around 20 tonnes of coffee in one 40ft container.
The container is lined with paper and moisture absorbent material to prevent moisture accumulation and risks of mold and spoilage.

Next time: Part 3 will focus on Transportation, Roasting and Resting.

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