To an expert, green coffeeGreen coffee refers to the processed seed of the coffee tree fruit. Coffee is a flowering shrub that produces fruit. The seeds of the fruit are processed, roasted,... is a text. It can be read bean by bean, telling the entire story of the coffee from the tree, through the processingThe removal of the cherry and parchment from the coffee seed.: Coffee is either wet-processed (also called washed or wet-milled) or dry-processed (also called wild, natural or natural..., sortingCoffee is sorted by size, density, and color in its preparation for export.: Sorting refers to several steps performed in the preparation of coffee for export. Coffee is... and screeningRunning coffee through a screen with holes of a fixed size to sort beans for size.: Running coffee through a screen with holes of a fixed size to....
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One of the most complexThe co-presence of many aroma and flavor attributes, with multiple layers. A general impression of a coffee, similar to judgments such as "balanced" or "structured" botanical forms is a flowering tree or shrub , such as coffee. As the tree goes through its many cycles of growth and dormancy, flowering and fruiting, many critical needs must be met to ensure a plant that is happy, healthy and wants to make a lot of fruit.
A coffee tree produces about one pound of roasted coffee per year! The seeds are an encapsulation of all the complexities of the trees, and with over 800 organicGrown without the use of artificial fertilizers, herbicides, etc.: Organic coffee has been grown according to organic farming techniques, typically without the use of artificial fertilizers. Some farms... constituents that contribute to the cup quality of the beverage, it is 2.5 times more chemically complex than wine. |
I am not an expert on defects (you have to work in the industrial/commercial end of the trade to see lots of bad coffee!), but I cup and roast coffee everyday. I prepared this image (below) from coffee samples in my “green coffee files” at the request of my customers. The image is not all-inclusive, and is not composed entirely of defects. There are charts of coffee defects available through the Specialty CoffeeSpecialty coffee was a term devised to mean higher levels of green coffee quality than average "industrial coffee" or "commercial coffee". At this point, the term is of... Association of America (scaa.org)
Do not misinterpret the presence of irregular beans in a coffee as the sole indication of its quality – what I call “eye-cupping”. Dry-processed coffees will always have more irregularities. Uneven preparationPreparation refers to the dry-milling steps of preparing coffee for export: hulling, grading, classifying, sorting.: Preparation refers to the dry-milling steps of preparing coffee for export: hulling, grading,... can even be considered part of the character of the coffee – with the off beans providing maybe some of characteristic earthiness as with some Indonesians or dry processed coffees.
The preparation is part of the “coffee culture” of a specific place, part of the common practice of the people who produce a specific coffee. An inexperienced roasted can easily interpret the presence of more silverskinOn dried green bean coffee, the thin inner-parchment layer that clings to the bean and lines the crease on the flat side. Silverskin becomes chaff and falls off... (chaffChaff is paper-like skin that comes off the coffee in the roasting process. Chaff from roasting is part of the innermost skin (the silverskin) of the coffee fruit...) that gives the coffee a very yellow appearance as a defectIn coffee, a defect refers to specific preparation problems with the green coffee, or a flavor problem found in the cupping process. Bad seeds in the green coffee.... You will see more silverskin on late harvested coffees no matter what the varietal.
Ultimately, the quality of a coffee is found in the cup.
Notes:
- If a coffee has irregular beans it doesn’t necessarily mean it is bad. The cup is ALWAYS the ultimate proving ground for the quality of a coffee. Some coffee by nature have a higher percentage of irregular beans and are considered top quality. It can be part of the character of the coffee – with the off beans providing a characteristic earthiness to the cup as in the case of many Indonesians or dry processed coffees. Even in coffees of top quality you can get a bad bean – as happened in a Cup of ExcellenceThe Cup of Excellence is a competition held yearly in many coffee-producing countries, designed to highlight the very best coffees from each origin.: The Cup of Excellence (COE)... competition in RwandaA Bourbon cultivar variant from Rwanda and Burundi. Bourbon coffees are named for the island in the India Ocean where French colonists grew it. Some history from the... a few years ago, when a few top coffees had potato defectA cup taint with the strong smell of raw potato, caused by a bacteria that then triggers a pyrazine reaction, resulting in the off flavor. This affects coffees... show up in the very late rounds.
- New cropRefers to fresh shipments of green coffee within the first month or two of the earliest arrivals ... not quite the same as Current Crop, which means the... wet-processed coffees are usually a deeper shade of green, but not necessarily.
- A black beanA coffee bean whose interior is totally back (endosperm), due to fungi, mold, yeast, pest. This happens with over-mature coffee cherry where the bean falls to the ground... (which is also called a “stinker” in an old text I have) is a seed that fully rotted in the fruit
- A “sour” bean is also called an underdeveloped bean. These are detected visually by an off color and a very wrinkled surface
- Overripe beans are also called “floaters” because in wet-processing they float and are skimmed off the water’s surface.
- Coffee is often sold at a particular screen size, such as 16 or 17/18. The presence of small and large beans compared to the norm is not a defect, but indicates some ineffectiveness in preparation.
- Peaberries are not defects and are often considered higher quality, for no great intrinsic reason. They will roast differently because of their size. They occur when one of the two ovules (or seeds/beans) aborts and the other can develop unrestricted into a round shape, filling out the space provided in the fruit.
- Not pictured are beans afflicted by a boring insect and foreign matter that counts as defects such as sticks, stones, seeds in their parchmentGreen coffee still in its outer shell, before dry-milling, is called Parchment coffee (pergamino). In the wet process, coffee is peeled, fermented, washed and then ready for drying..., pods, fingers ….
- The Green Coffee Association has a page of defects and grading.
Two Important Questions:
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What does good “new crop/ current crop” green coffee look like?
Firstly, good green coffee from many origins has a different look based on preparation standards, processing (wet, dry, semi, pulped, etc). The SCAA distributes a poster of the green coffee grades, but it is based upon wet-processed coffee, and is quite useless for judging other processess and odd-looking cultivars.
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What does old green coffee look like?
Past cropRefers to an older coffee not from the "New Crop" or the "Current Crop". Cuppers will even use it as a general term for baggy, old hay or... green coffee may look different, dried out perhaps, but it may not; you have to taste it to be sure. An older crop coffee will generally roast more quickly, which the moisture content of the beans has most likely changed due to prolonged storageGreen coffee can be stored much longer than roasted coffee: Roasted coffee starts to lose its aromatics in 10 days after roasting. Green coffee can be stored months.... What happens most often is that the bright coffees will fade, and start to taste flat. The coffee may also absorb the flavor of what it is stored in – and become “baggy”.
- Some of the worst defects are impossible to see, phenolic coffee in particular. Phenol defect is found in many origins, but is most identifiable in ColombiaColombian coffee is highly marketed and widely available in the US. They have been largely successful at equating the name Colombian Coffee with "Good" Coffee. This is half-true.... and BrazilBrazil is a coffee giant . As Frank Sinatra sang, "they grow an awful lot of coffee in Brazil".: Brazil is a coffee giant . As Frank Sinatra... (I have encountered it in MexicoMexican coffee originates from South-central to Southern regions of the country. For that reason, coffees from Coatepec and Veracruz are much different from Oaxacan Plumas, which are in..., HondurasHonduran coffee was absent from the top ranks of the Specialty market, but that has changed. It has all the environmental factors on its side: soil, altitude, climate...., and NicaraguaNicaraguan coffees from the Segovia, Jinotega, Ocotal and Matagalpa regions are nice balanced cups. They often possess interesting cup character along with body and balance, outperforming many other... to a greater extent than in El SalvadorEl Salvador coffee had an undeservingly poor reputation for years, marred mostly by the inability to deliver coffee of high quality in an unstable political climate. Unfortunately, agriculture... and GuatemalaGuatemalan coffee is considered a top quality coffee producer in Central America. Due to our proximity to Guatemala, some of the nicest coffees from this origin come to... … not sure what implications can be drawn from that.) No conclusive research has proven the cause of phenol in the cup, but it is one of the most obvious defects to taste. It is a dirty, sulpherous flavor, very potent both in the aromatics and cup flavors. And you cannot see it: the green and roasted seed appear as a wholesome coffee bean.
- Some have posited that the cause is on the tree, in particular that it comes from trees with a consistently sunny side and a consistently shaded side. Others say it is from bad processing, that it is microbial. Others say it is the tree’s defence from the Broca (the coffee berry boring insect). Based on my experience, I side with the microbial explanation. Phenol shares sensorial attributes with volatile sulpher compounds, such as hydrogen sulfide. Whether this occurs on the tree or in the processing is unclear. Phenol defect can be present in some of the best coffees, produced at the finest mills.
Also of interest: Single Bean Macro Photos of Green Coffee and Weird Stuff We Find in Coffee