Sumatran Coffee: Grading and Appearance

Oct. 18. 2019

 

The appearance of 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,... from SumatraIndonesians are available as a unique wet-hulled or dry-hulled (washed) coffees. Giling Basah is the name for the wet-hulling process in Bahasa language, and will have more body... can be jarring, especially if you’re used to washed beans from Africa or Central America. Why, many ask, does a Grade 1 Sumatra lack uniformity of color and/or bean size? Why do we see more “ugly” beans in Indonesian green coffee? 

 

Let’s start by discussing a few terms – you can find more definitions in our Coffee Glossary: 

 

Grade: There is no universal grading scale for green coffee – in fact, nearly every country has its own grading scale. Grading can also be an unreliable measure of quality; sometimes a coffee earns a higher grade than it deserves, other times the grade is lowered to avoid tariffs. Grading in Sumatra is based on cup quality rather than appearance, so you can see a Grade 1 Sumatran coffee with up to 8% defects but high cuppingCupping is a method of tasting coffee by steeping grounds in separate cups for discrete amounts of ground coffee, to reveal good flavors and defects to their fullest.... scores. 

 

Appearance: Refers to the amount of defects in a particular coffee. We list appearance under the “Specs” portion of every coffee review. Our appearance rating is a little confusing but the gist of it is, the decimal number represents the amount of secondary defects found out of the 5 secondary 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... allowance in “Specialty Grade” coffee.

 

Going with shells as our example, this 5 secondary defect allowance means we would technically allow up to 50 shell beans in 300 grams of coffee. If there were 30 shells, the calculation that goes into our Appearance category would be: 30 shells = 3 secondary defects; 3 (secondary defects) / 5 (allowance) = .6 defects per 300 grams. 

 

Defect: Refers to specific 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,... problems with the green coffee, or a flavor problem found in the cupping process. Bad seeds in the green coffee sample are termed defects, and scored against the coffee to determine its grade. Roast problems sometimes produce defect flavors, as do poor 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.../preparation of the coffee, mistakes in transportation and 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..., problems at the wet millThe wet mill is a processing center where coffee cherry from the tree is brought for initial processing.: The wet mill goes by many names (Beneficio, Factory, Washing..., bad picking of the fruit or problems going back to the tree itself.

 

Here’s what Dan, one of our coffee buyers, has to say about defects: 

 

“Talking defects is so tricky because there’s nothing cut and dry about it. I feel like the term “defect” lends to an assumption that the coffee is bad, or at least tastes bad. The truth is there’s a whole range of defect types and the impact they have on the cup (if any) will vary. Coffee is produce and uniformity is a very hard thing to mitigate, especially since the size is so small. This doesn’t mean we don’t care how a coffee looks, because we do. But I think that when discussing defects as they are outlined in manuals such as the SCASCA is the newly formed global coffee association for Specialty Coffee. The former organization called SCAA was incorporated into the new group. The main commercial coffee group is... handbook, it’s important to keep in mind that just because a coffee is not uniform and qualifies as a “defect” (I’m generally talking about secondary defects here), it doesn’t mean it tastes bad. Conversely, a terrible coffee can be nearly 100% defect free, have stable moisture, and even be a “good” cultivarCultivar is a term used interchangeably with Varietal in the coffee trade to indicate plant material, although there are distinctions.: The naming of a cultivar should conform to... like CaturraCatimor is a broad group of cultivars derived from a Hibrido de Timor (HdT) and Caturra cross, highly productive, sometimes with inferior cup flavor. The main issue is... or BourbonA coffee cultivar; a cross between Typica and Bourbon, originally grown in Brazil: Mundo Novo is a commercial coffee cultivar; a natural hybrid between "Sumatra" and Red Bourbon,... but cup very poorly. In short, visual judgement should never replace taste.

 

On culling, I do think it’s useful for picking out really nasty beans, but maybe not so important for every little broken, bug holed, or mis-shapen coffee. The majority of these are what are considered secondary defects and have a pretty high allowance when calculating grade number. And most importantly, they don’t really have an affect on flavor.”

 

Sumatran coffees are tricky in that they tend to be riddled with defects no matter what the grade. There are a few reasons for this, such as weather and 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... method. That doesn’t mean they get a pass in our appearance count!  We receive a huge varietyA botanical variety is a rank in the taxonomic hierarchy below the rank of species and subspecies and above the rank of form (form / variety / subspecies... of unsolicited samples from producers in IndonesiaUSDA is (obviously) the United States Department of Agriculture. USDA also had coffee plant breeding programs in the past and one variety they distributed to Indonesia and was..., and it’s worth noting that most of the “Grade 1” coffee looks far worse than any coffee we ultimately purchase for resale. In his explanation of Giling Basah processing, common in Sumatra, Tom explains how we choose Sumatran coffees: 

 

“When Sweet Maria’s started back in ’97, right in the middle of this “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... as carbon-water” era, the samples of Sumatra coffees I looked at were hideous. And for perhaps a decade after that, many Indonesian coffees were exported with impunity, as “Grade 1 Mandheling” seemed to mean nothing, and 100+ physical defects per 350 gram sample of green beans was common. Indonesian exporters, perhaps as the most dubious in the coffee world, were not only given a free pass on the cupping table, but in terms of cleanliness of coffee preparation as well…It takes a lot of cupping and identifying a different set of reference points to determine what a really good wet-hulled Sumatra should be. In our lab we also check the defect count, ultra-violet appearance of the coffee, water activity, humidity, and densityThe density of a coffee bean is often taken as a sign of quality, as a more dense bean will roast more with a better dynamic. The density... of the bean. These tell the story of the coffee, but ultimately we find that cupping reveals the truth just as well.“

 

Our main takeaway? Don’t judge a book by its cover! If you’re taking a crackAn audible popping sound heard during roasting. In coffee, one refers to "first crack" and "second crack," which come from two different classes of chemical reactions.: An audible... at roasting Sumatra or another Indonesian coffeeIndonesian coffee is known for its unique earthy, potent flavors. Some like it, some hate it, but it's certainly distinctive. Much of the coffee in Indonesia is processed..., trust your palate over your eyes. If you do see something that seems amiss, don’t worry – feel free to email us a photo to [email protected] and we can take a look. For more information, check out our Sumatra Origin Page.

 

-Ryan