Buying Specialty Green Coffee
green coffee seller is responsible for grading
coffee beans before sending the coffee to the buyer. Once
graded, "Exceptional" and "Specialty"
green coffee beans can still have problems that are not necessarily
accounted for in coffee grading. These coffee "defects"
are less serious, but harm the potential of the coffee.
You can tell a great deal about the processing conditions
of a coffee by looking at the appearance of the green coffee beans.
Although cupping is the definitive way to check for problems,
a good prognostic tool is to compare coffee beans.
Things to Consider when Buying Coffee:
1. The green coffee beans should
be of nearly equal size 17/18, 15/16, 13/14 etc, be similarly
shaped, and have a similar color. The reason for this
has to do with how evenly the coffee will roast which will
affect the appearance and taste of the roasted coffee.
Smaller coffee beans will roast differently than larger beans resulting
in an uneven cup. Uneven coloring hints toward drying
problems, whereas uneven shapes may indicate a mixing of
2. Ensure that the producer
separates coffee lots by both geographic area and
coffee varietal. These lots should be harvested, processed, and cupped
separately before blending in the silos.
3. Washed Arabica coffees should be even and bright. The coffee beans should not have an
uneven or dull color. If they do, they are likely to have
been dried or processed incorrectly. Coffee processing is essential for specialty green coffee. If the green coffee
beans look faded, the cup quality will be faded.
4. Inquire about the
coffee drying conditions on the coffee estate. If they seem to have
invested a significant amount of time into ensuring that
they are drying the coffee properly, the coffee quality will generally show this in the cup.
Improper drying on patios or in mechanical dryers can usually
be observed visually. Rapid drying in mechanical dryers
results in dull or brown coffees. Coffee beans that are mottled
(or quakers when roasted) result when the coffee is dried
too quickly, spread too thin on the patios, or not rotated
as frequently as recommended. Some people recommend
drying coffee on patios first to dry the skin, then transfer to
mechanical dryers, and then bring the coffee back to the
patios for the final drying. They believe that this
helps improve color. Others send coffee beans to the dryers
several times, while in between drying sessions they allow
the coffees to rest in silos so that the moisture content
of the bean can come to equilibrium. This is important
since the outside of the coffee bean will dry faster than the inside
of the bean. Inquire about the temperature used on
the dryers. Is it over 42°C? If so you can expect
a dull or baked cup, resulting in a coffee grade that is less than desirable.
5. For all coffees, inquire
about the coffee processing. Make sure they process the coffee estate is processing green coffee beans
immediately upon harvesting. Otherwise you are guaranteed
a fermented cup since coffee begins fermenting immediately
upon picking. Ask how they use the fermentation tanks
and why? Do they separate out coffees that float to
the top of the tanks during fermentation? After pulping,
do they separate coffees by density before they add them
to the tanks? Only coffee estates that have dedicated a significant
amount of time to improving coffee quality will know why these
steps are important and necessary. If coffee pulp
is present in the tanks during processing, it can result
in brownish tinges on the green coffee beans. This is also
indicative of harvesting over-ripe coffee cherries.
6. Natural (dry) processed coffees will often be covered in brown silverskin which
has attached itself to the bean. In Brazil they call
this a "fox bean" and it is not considered a defect.
Novice classifiers might expect this type of bean to be
a defect, but if you can remove a portion of the silver-skin
by rubbing on the black sorting mat it is not considered
a defect. Green (under ripe) coffee also has a silver-skin attached
to it, but this cannot be removed by simple rubbing.
In a washed coffee, fox beans may indicate sour, fruity,
or Rio tastes. This should be confirmed in the cup
and not visually.
Do the coffee beans have a little pink skin covering them or inside
the crack of the bean? In some areas this is a serious
defect which most people do not consider to be a defect.
Since it is not a part of the green coffee classification,
these beans could be passed on to the buyer as specialty
coffee. These coffee beans should be separated and cupped
to determine if the defect is serious.
Are the coffee beans whitish or faded around the edges? This
is likely a result of insufficient drying or storage in
humid conditions. The cup will be bland and ordinary. These white marks are also observed in coffees
that have not been dried evenly. The portion of the bean
that has a whitish tone has higher moisture than the other
parts of the bean. Whitish or discolored coffee beans can
also result from oxidation, contact with the earth, or polluted
9. Before you buy green coffee beans, smell them. Ferment and smoke
damage can be easily detected at this point, whereas they
might be more subtle when roasted.
10. Pick up the green coffee beans. How do they feel?
If they feel glass-like and fragile, they have been over
or dried at too high of a temperature. If they are pliable,
they have not been dried sufficiently and should be rejected
since mold growth at this point is unavoidable.
For more information about buying specialty coffee, visit Visit Lucidcafe.com.
Characteristics of Processed Coffee
Green Coffee Classification
Moisture Percent Meter