Sumatra

Sumatra coffees are famous for their peculiar flavor profile, low acidity, thick body, and rustic flavors that can often be described as earthy. Much of the flavor comes from the way Sumatras are processed, the wet-hull method , not to be confused with wet-processed coffee. The flavor of typical wet-hull Sumatra is polarizing among buyers. Some love it, but they must bracket this type of flavor profile because it would be considered unacceptable from any other origin besides Indonesia. Each coffee drinker has to discover if this type of flavor is right for them, or not; whether it's a go-to daily drinker, an occasional diversion, or flat-out unacceptable.

On a cupping table of well-processed Central American coffees, a Sumatra would immediately be thrown out. The earthy and foresty flavors - herbal, sometimes mossy or even mushroomy - would be attributed to processing errors, and the coffee labeled defective. So why this schism in the way the coffee trade treats wet-hull Indonesia coffees, and Sumatra in particular?

It comes down to taste: If a Sumatra supplier can consistently provide the same coffee, processed the same way, be it fruity or earthy, there are buyers who see this as a uniquely different flavor profile, and a welcome break from the Central America, Colombia or Kenya coffees. And of course the bottom line is that their customers like it. Those who like minimally-processed wines, or those wines with complex flavors of leather, peat moss, fir, cedar, humus, tannins, will see something in the Sumatra flavor profile.

Indonesian coffees like Sumatra are nearly always processed by the wet-hull method. Wet-hulled coffee is called Giling Basah in Bahasa language. Most coffee in Indonesia is grown on small-holder farms, a family with anywhere between 100 trees to a few hectares of land. They pick the coffee and pulp it, which means that they run it through a hand-crank drum with a surface like a cheese grater that peels off the skin of the fruit. Then they will ferment the coffee in any number of ways - either in a polypropylene bag, a plastic tub, or a concrete tank - to get the fruit layer (mucilage) to break down. After overnight fermentation, the mucilage can be washed off, and you have wet parchment coffee - the green bean inside the parchment layer that encompasses it, still swollen with water.

Sometimes origins like Sumatra are available as a true wet-processed coffee (although this term would probably not apply well, a better description would be dry-hulled). In wet-processing a farm would slowly dry this coffee for days or weeks, usually on a patio or raised bed, or sometimes in a mechanical dryer, down to 10-11.5 % moisture. In this process, the green bean would become the small dried seed we know, and the thin parchment shell is removed, preparing the coffee for export.

But in Sumatra and other parts of Indonesia, the farmer doesn't want to wait for all this to happen - they want to get paid! They want to do as little work to process the coffee, and get cash. And who can blame them? So they take their clean wet parchment coffee, dry it a few hours until it has 50% moisture content, and sell it to a collector middleman, or deliver it to a mill. They get paid faster, and do less work this way.

The mill might dry the coffee a little bit more, a day or two, but in general they send it to a special machine (the wet-huller) when the coffee still has 25-35% moisture content. This machine uses a lot of friction to take the tightly-attached parchment layer and tear it from the water-swollen green bean, which at this stage is often white and looks nothing like the green bean we finally see. Then the coffee is laid out to dry, totally unprotected by any outer layer, on a patio, on a tarp, on the road, or sometimes on the dirt! Drying without the shell is rapid, so the mill is able to sell the coffee and get paid with rapidity.

What does this do to the coffee? It creates a lower-acid cup, less brightness, and seems to enhance body. But the risk is great: the wet and unprotected green bean can easily be damaged in the hulling, or on the drying patio. No farmer in Central America would think of exposing their green bean direct to the patio or bed without the parchment layer. This layer protects the coffee from taints, keeps it clean, and allows a slower, gentler, more uniform drying. And coffees that are dried well will last longer when they arrive at the buyers; good tastes won't fade quickly into papery or burlap bag flavors.

This might make is sound like all wet-hulled coffee is bad, since this method isn't rooted in creating good-tasting coffee, but rather speeding up the process. But there is good vs. bad wet-hulled coffee. There are mills drying coffee on patios so clean you could eat off them, covered in a green-house like structure to protect from the unpredictable Sumatra rains, treating the coffee with great respect, and consistently producing great lots. It takes a lot of cupping, and identifying a different set of reference points to determine what a really good wet-hull Sumatra should be.

We look for sweetness in the cup, an expanded definition of sweetness than one might use when cupping other origins. This could be raw sugar, like muscavado, or molasses. It could be unique syrups like brown rice syrup, or sorghum syrup. In any case, a coffee with no sweetness is rarely, if ever a good coffee. We look at the rustic elements to distinguish gross flavors like dirt from positive clean-earth, humus or other positive and relatively clean natural scents and tastes. While slight green herb and mossy is good, vegetal notes that are too bittering hint at poor processing or under-ripe fruits. In our lab we also check the defect count, ultra-violet appearance of the coffee, water activity, humidity and density of the bean. These tell the story of the coffee, but ultimately we find that cupping reveals the truth just as well.

Sumatra was planted in coffee after the crop was introduced to Java in Indonesia. Arabica production in Sumatra began in the 18th century under Dutch colonial domination, introduced first to the northern region of Aceh around Lake Tawar. Coffee is still widely produced in these northern regions of Aceh (Takengon, Bener Mariah) as well as in the Lake Toba region (Lintong Nihuta, Dairi-Sidikalang, Siborongborong, Dolok Sanggul, and Seribu Dolok) to the southwest of Medan.

In the past, Sumatra coffees have not been sold by region, because presumably the regional differences are not that distinct. Rather, the quality of the picking, preparation and processing of the coffee determines much of the cup character in this coffee. In fact, Sumatras are sold as Mandheling (Mandailing) which is simply the Indonesian ethnic group that was once involved in coffee production. The coffee is scored by defects in the cup, not physical defects of the green coffee. So a fairly ugly-looking green coffee can technically be called Grade 1 Mandheling. A grade 1 coffee can be a good cup or a very dirty and ugly-tasting coffee. The grading sometimes seems arbitrary by any standard. The way coffee is shipped via the humid port of Medan also damages quality as it can gain moisture before shipping, then flash dried in the hot, hot sun to get it back down to an acceptable level. This ruins cup quality.

The main story behind the coffee here is processing, but the varieties of coffee grown do factor into the cup, and certainly into the farming practice. Sumatra has a range of cultivars. The original Typica type was brought from Yemen or Ethiopia via India. This is sometimes called Jember Typica. There are 2 main Typica types: Bergandal and Sidikalang. Hibrido de Timor, a cross between arabica and robusta, is sometimes found with the name "TimTim" ... we offered TimTim Blangili a while back. The majority of coffees are arabica types that have robusta inputs, like the Catimor coffees found in Central America. Ethiopia strains were reintroduced with the names Rambung and Abyssinia, which were brought to Java in 1928, and later to Aceh, Sumatra. Another group of Ethiopian varieties found in Sumatra are called “USDA". Knowing the specific cultivar is nearly impossible, and they are often a mix of many. In Sulawesi for example, Djember means S-795 from India, not a pure Typica. Many Aceh coffees are Ateng types of catimor, although there is still old varieties of coffee tucked away in this zone. Our Lintongs are a mix of Onan Ganjang, Djembers, and Ateng types. All of this is really second fiddle to the process flavors, the Indonesia wet-hull method called Giling Basah. Process flavors trump all in the Sumatra cup.

Sumatra faces many problems in coffee cultivation. There are types of fungus such as leaf rust. But the most damage to the crop and the livelihood of the small farmer is CBB - the Coffee Berry Borer - or Broca, as it is called in Latin America. Broca runs rampant in most areas of Sumatra. The small beetle drills into the fruit and seed while it is on the tree, and these beans must be sorted out from top grade coffees before they are exported. It is forced from the bean in processing, so the insect itself is not a risk but the damage it does to the bean and the plant's reaction to the attack will result in a whole host of defect flavors in the cup.

On my last trip to Sumatra I was shocked at the amount of Broca I saw on the plant, and also on the wet parchment coffee. They were all over the bags in the local markets where coffee is traded. It was very sad both for the damage to the cup quality, as well as the value and volume of the crop. There are natural control methods, like alcohol traps made from used 2 liter soda bottles. But one of the best prevention methods is to pick coffee promptly when it is mature, and not let coffee fall to the ground. The borer only wants to live in the ripe fruit. But Sumatra has a poorly defined crop cycle and weather patterns, meaning the coffee shrub often has ripe fruit on it. It's like a Broca motel - the borer always find a room available.

There is a tendency to over-roast Indonesians. The reason is that they don't show as much roast color, and have a mottled appearance up until 2nd crack and even a bit into it. Don't let this make you think you have to roast them dark (although they can be nice this way too). Great Indonesians will be wonderful roasted just to the verge of 2nd crack but NOT into it at all. So ignore the weird beans you see green, and ignore the mottled appearance of lighter roasts, and only focus on the what you get in the cup.

With prices high, you expect quality would be up too. But in general this is not the case. What's the incentive to pick and prepare coffee better when the market guarantees a premium anyway? It's why we buy very selectively from Sumatra and cup our lots hard. What I have seen is blends of old crop and new crop early in the Grade 1 window (Nov-Jan in particular), which is a deceptive practice. Nonetheless, roasters need Sumatra and I am sure someone buys it ... someone who doesn't cup their lots that is! Problems aside, we have been able to find great Sumatras in both the traditional rustic flavor category, and cleaner, well-processed types, because we have established good relations directly with the sources.

Sumatra Toba Batak Peaberry
$6.45
$12.26
$28.06
$53.54
$102.33
Ibu Manurund pulping coffee in Lintong, from my trip last year
Arrival dateFebruary 2014 Arrival
Appearance.6 d/300gr, 16+ PB screen
GradeOne
ProcessingWet Hulled (Giling Basah)
RegionLintong Nihota, Lake Toba Area, N. Sumatra
Varietal(s)Ateng, Djember
Intensity/Prime attributeMedium-Bold intensity / Complex aromas, rustic sweetness, spice and tea.
RoastCity+ to Full City+ roast is recommended here.

This is a peaberry preparation of our Lintong-area coffee. Lintong coffees are from Sumatra, the island that is politically and geographically part of Indonesia. Lintong Nihota is the town that has become synonymous with the entire southern part of Lake Toba area. Lake Toba defines the landscape of the area, the largest volcanic crater lake in the world, and the result of the largest volcanic event on earth in the last 25 million years! It is huge, and the coffees from the north and eastern shores are quite different from the Lintong coffees. Lintong coffees are farmed by the Batak peoples that are the indigenous tribe that works the coffee in this area. The family of collectors we source this lot from works direct with the small growers, bypassing the local markets in most cases, where lower grade coffees are mixed in with the better lots. This peaberry can take light roasts as well as dark. Many commercial roasters use color and surface texture as indicators of roast level, and tend to go dark on Sumatras in general because of this. The peaberry has a different roast dynamic, and seems to be a more dense bean that the flat beans from the same region.

The dry fragrance of this coffee has a strong rustic sweetness in lighter roasts, brown rice syrup and raisin, with banana and a hint of sweet tobacco. Darker roasts are very fruited and sweet with allusions to red berries and dark caramel. There's fruited accents in the wet aroma too, baked apple and mulling spices, raisin and cinnamon - and the break produces a nice culmination of papaya and buttery caramel. This is a very sweet set of smells which help define the cup. There's flavors of rhubarb pie, spiced apple cider, and rindy citrus acidity. This brightness paired with intense sweetness is unique in Sumatra wet-hulled coffees. There's a dark caramelized sugar note, with a slightly rustic herbaceous note. The finish has a nice black tea note along with a clean brown sugar and fruit sweetness to it. All in all, this is one of the nicer brewed or pour-over Sumatra coffees. It's one that can change the minds of tasters used to simple, earthy coffees from this part of the world.

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Sumatra Lintong Aek Nauli
$6.45
$12.26
$28.06
$53.54
$102.33
Beautifully kept crop in Lintong Nihota, Sumatra
Arrival dateFebruary 2014 Arrival
Appearance.4 d/300gr, 17-18 Screen
GradeOne
ProcessingWet Hulled (Giling Basah)
RegionLintong Area, N. Sumatra
Varietal(s)Bergendal, Djember
Intensity/Prime attributeMedium-Bold intensity / Intensely sweet aromatics, fruited, slight herbal notes
RoastCity+ to FC+. I'd start out in the Full City range and taylor the roast to your liking from there.

his coffee from the village of Aek Nauli is Lintong coffee at it's best. Within the Lintong Nihota area, Aek Nauli lies due west of Dolok Sanggul, another region we buy coffee from regularly. It's just about 5km down the road, so very close, and you can see the Onan Ganjang highlands in the distance. Much of this area's Landscape is defined by Lake Toba, the largest volcanic crater lake in the world. It's gigantic, and the coffees from around this area can be truly unique. 'Aek Nauli' translates to 'village with 1,000 ponds' - ironically it's difficult to find much water in the surrounding area, but there is a small river in Aek Nauli. The people of Aek Nauli rely on rain water for much of their daily water consumption, and this is used for agriculture as well. We work with a mill who buys directly from the farmers, many in the surrounding highlands, keeping lots separated and intact. This is one reason for the top quality of this coffee, the other being meticulous and repetitive sorting during milling - much more so than most Grade 1 Mandhelings.

This lot from Aek Nauli is Lintong coffee at it's best. Even with the rustic elements you might expect from Lintong coffee, there's a relative cleanliness that follows through from dry fragrance to the cup. The dry grounds have a sweet smell of toasted marshmallow, dried cocoanut and red raspberry, as well as an earthy smell of grain sweeteners like brown rice syrup. The sweetness found in the wet aroma is pretty incredible - an intense scent of maple bar frosting along with a raspberry sauce smell comes up in the steam. Breaking the crust reveals notes of dried apple chips and sorghum syrup. This coffee cups nicely, with lots of up-front sweetness. The flavors vacillate between complex sugars like brown rice syrup and caramel sauce, and fruited notes like muscat grape, rhubarb, and citrus. Flavors shift a bit as the cup cools, opening up to a much more in the way of juicy fruits as well as modest acidity. There is a tarragon note too, and these rustic elements are kept well in balance. The finish has lots of citrus zest and cacao nibs, with a pleasantly bittering effect in the long aftertaste.

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Sumatra Onan Ganjang Cultivar
$6.40
$12.16
$27.84
The leaves of the distinct Onan Ganjang tree, North Sumatra.
Arrival dateFebruary 2014 Arrival
Appearance.4 d/300gr, 17-18 Screen
GradeOne
ProcessingWet Hulled (Giling Basah)
RegionLintong Area, N. Sumatra
Varietal(s)Ateng, Bergendal, Onan Ganjang
Intensity/Prime attributeBold intensity / Slightly herbal, rustic sweetness, syrupy body
RoastCity+ to FC+ to Vienna. Full City was my favorite. Allow this coffee to rest 2-3 days after roasting and before brewing

Onan Ganjang is a town and sub-district in the Lintong area, on the southern shores of the huge volcanic cratar lake, Laut Toba. Coffees from this area have a specific cup profile that is different from Aceh coffees, from the far north. The coffees here are of mixed heritage; a few Bergendal Typicas exist mixed in with the predominate Ateng catimor types. This lot represents a third type, Onan Ganjang, named for the locality where it was widely planted (also sp. Onang Ganjang), but referring to a specific cultivar. To be clear, it's not a Typica type, and it could be a local mutation crossed between Hibrido de Timor and Ateng. But the tree itself is distinctive, healthy, disease-resistant, and produces well. In the cup, the difference is subtle but clear as well; classic flavors, less herbal than other Lintong lots, balanced. This year's production was fairly low in the highlands of neighboring city of Dolok Sanguul, and so we decided to blend a few bags in with this lot - so there is a bit of Ateng and Bergendal mixed in which really worked out well in the cup. This is another premium selection, with the highest quality parchment coffee and best milling and sorting techniques. Lintong coffees are farmed by the Batak peoples that are the indigenous tribe that works the coffee in this area. This Batak coffee is a near-zero defect prepartion, without the usual split beans, broken pieces and crud found in standard Sumatras. It is carefully density sorted and triple-hand-sorted.

This is definitely one of the sweeter smelling Sumatra coffees that we bring in. The dry fragrance is potent and has hints of malted sugar, cinnamon and cardamom spices, fresh tobacco, and tropical fruits, especially at lighter roast levels. Notes of baking chocolate really come through at Full City roast, and the coffee remains very sweet aromatically. The wet fragrance is so sweet and has dark caramel and maple notes, along with a scent of pineapple syrup and apple/cinnamon bread. Herbaceous notes connoting origin come through as well, along with rice syrup, concord grape, and cola. The cup is very syrupy, with a bit of sarsaparilla fading into cocoa bitterness. The light roast has a zesty flavor, like orange or pink grapefruit, and a burned caramel sweetness. Darker roasts have an herbal element, as well as a heavy, stone fruit nectar juiciness, and roast flavors balanced between cola and chocolate. The complexity really builds and you'll taste tropical fruits, fresh herbs, layered chocolate, and lots else as it cools. Full City roast seems ideal for this coffee, but it has a profile that holds up just fine at City+ as well as Full City+. Give this one a whirl as an unconventional, but delicious, SO espresso.

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Sumatra Lintong Sijamapola
$6.10
$11.59
$26.54
$50.63
$96.94
Bag fermentation in Batak
Arrival dateDecember 2013 Arrival
Appearance.4 d/300gr, 16-18 Screen
GradeOne
ProcessingWet Hulled (Giling Basah)
RegionLintong Nihota, Lake Toba Area, N. Sumatra
Varietal(s)Ateng, Bergendal, Djember, Typica
Intensity/Prime attributeMedium intensity / Caramel sugars, tropical fruits, herbaceous
RoastCity+ to Full City+

This lot is from the Sijamapola locality in the Batak area of Sumatra, the Lintong region, along the Southern end of Lake Toba. The climate is great for growing coffee and it's a part of Sumatra we've worked in extensively over the past few years. The farmers are rewarded for different tiers of coffee, thus encouraging selection of optimally ripe cherry as well as thorough initial sorting measures. Most of the collectors that process the coffee are now using covered drying patios to create even drying of the wet-hulled coffee, resulting in cleaner cup quality. Sijamapola is a great example of what a difference proper cherry selection and processing can make in the resulting cup. It stood out on the table as having a relatively clean sweetness for a wet-hulled coffee, and without too much of the rustic appeal.

The dry grounds have an interesting warming spice smell to them, like cinnamon and clove. There is a "rustic" element to the sweetness, but it's like brow rice syrup and with heavy allusions to caramelizing sugar. Full City roasts take on layers of aromatic woods, like cedar or rosewood. There's a smoky chipotle smell as well in dark roasts that has as much to do with varietal as roast level. Light roasts are so sweet with hot water added, and the crust smells like cream caramel and raspberry. Dark roasts cross over into burned sugar smell of creme brûlée crust and with a slight note of cumin spice. The cup is sweet, and with a pungent fruit flavor of jackfruit. Subtle tropical fruit notes come out in the cooling cup, and there's a faint flavor of citrus zest. I wouldn't say the acidity pops, but it's more defined than standard Sumatra coffee. It's like apple juice and lends itself to a weighty, clean mouthfeel. The finish is sweet, and with a lingering flavor of herbal tea. Our dark roast was just outside Full City+ territory and was still very sweet, juicy, and with herbaceous flavors of basil and tarragon. It's a nice cup of coffee that will also do well as an "outside the box" single-origin espresso.

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