Intro by Evan Gilman
The area around Kayu Aro is known mostly for its tea plantations, but further up the hillside (or rather, the side of Mount Kerinci) there are some newer coffee growing areas, not the least of which are the smallholder farms of the members of Koperasi ALKO.
Hailing from 22 villages, these 17 farmers’ groups (4 of which are exclusively for women) bring their coffee to a central processing facility for export readiness. Coffee is only brought down to a lower elevation once it is ready to be shipped immediately, something that can really improve the chances of maintaining a coffee’s quality.
Just down the road from Kerinci Sablat National Park, these farmers are using intercropping techniques and growing coffee alongside cabbage, orange trees, ginger, and a number of other crops. The particular coffee they grow in this region (and one of the most common cultivars in Indonesia) is S795. This cultivar came about as a cross between S288 and Kent, with the former being a spontaneous cross between C. arabica and C. liberica. Many of the seeds are pointy like a liberica, but the flavor is distinctly arabica.
This is one of the cleanest and freshest-tasting Sumatran coffees we’ve had the pleasure to taste this year. Taking a look at the social media accounts of Koperasi ALKO and tags of AgroTropic Nusantara, you can see their cherry selection is on point, and their processing facilities are crisp and clean – and their effort is clearly reflected in our experience of this fantastic coffee. If you’re looking for an impressively clean Sumatran coffee, this is it.
Green Analysis by Nate Lumpkin
This wet-hulled coffee from Sumatra comes to us with average density, somewhat above average moisture content, and somewhat above average water activity. This coffee has a wide screen size distribution, although the majority of the coffee falls into size 17 and above, with only 38% under that. Its wide screen size could introduce uneven roasts, especially in a faster roast, so consider slowing down the roast during color change.
The cultivar S795, also known as Jember and Linie S, is widely used in Indonesia. Jember is a disease resistant hybrid bred from two resistant parents, Kent and S228, the former of which is a resistant Typica selection, while the latter is a spontaneous hybrid of Coffea liberica and Ethiopia’s indigenous arabica. This cultivar was developed in India, although the name Jember refers to a regency in East Java.
Ikawa Analysis by Chris Kornman
We’ve updated our V2 Ikawa Pro machines with the latest Firmware version (24) and run on “closed loop” setting. Our roasters underwent full service in October of 2018 which included replacement heating elements and an updated PT 1000 temperature sensor, and were recalibrated in September 2019.
This is a pretty far cry from the wet hulled “Mandheling” coffees of noted fame and questionable provenance and quality. Rather, this highly traceable and immaculately prepared Kerinci coffee is an absolute pleasure from start to finish. One of the hallmarks of common wet hulling practices can be a lot of crushed beans from poorly calibrated parchment hulling equipment. Here, however, the beans are pristine and ready for roasting.
I chose two opposing profiles this week, and actually cupped them in comparison with similar roasts of a prior release, CJO1340 (now sold out), an organic Takengon (also a wet hulled coffee). The Takengon is far more classic in terms of wet hull flavor profile: heavy and earthy, with plenty of peppery herbal flavors.
This Kerinci, however, handled the low and high airflow profiles admirably and shows off a lot of really pristine flavor notes. The first roast, a 7-minute low airflow profile (blue), came off just a little thin but with a lot of citrus zest including some grapefruit, accented by a nice fresh basil aroma and a sugarcane and raspberry-like sweetness.
It was the fast roast with higher airflow that really blew me away, though (red). This standard sample roast profile offered up a precise, dense and balanced flavor profile, centered on blackberry juice and fresh mango, with a juicy citrus acidity and a perfectly integrated caramelized sugar sweetness.
When CEO Max Nicholas-Fulmer told me he’d picked this coffee for a Crown Jewel, he called it “about as perfect an example of wet hulling done well as you’ll ever find.” I’m pleased to confirm that this is, indeed, a near-perfect coffee, regardless of hulling style… which I think is saying quite a lot.
You can download the profile to your Ikawa Pro app here:
Roast 1: Crown 7m SR Low AF
Roast 2: Crown Standard SR 1.0
Behmor Analysis by Evan Gilman
Unless otherwise noted, I follow a set standard of operations for all my Behmor roasts. Generally, I’ll use the 1lb setting, manual mode (P5), full power, and high drum speed until crack. Read my original post and stats here.
I’m a big fan of Sumatran coffees, and when an exemplary coffee comes in to perform analysis on, I get even more excited. One of the hallmarks of a great Sumatran coffee for me is that it looks and smells like what I saw when I was in Sumatra. What does that mean? Well, for starters, the shipment went off without a hitch and the coffee seems fresh – undamaged and without moisture-related issues which usually present themselves as splotches of color across a bean, or as shriveled or pale beans mixed in. This coffee looks great – even coloration, good prep, small distribution of bean sizes.. and it even smells fresh!
One thing to watch out for in the Behmor is that you might encounter a few beans stuck in the perforations of the drum – this coffee has a few pointy beans that have a tendency to get jammed in the drum. I only found one in my roast, but it’s worth noting.
I wanted to roast this coffee as I would any other Sumatran; with the majority of my efforts going towards sugar development and elongation of Maillard. At the same time, I didn’t want to imbue the coffee with any smoky or roasty flavors, so I tried to abate as much smoke as possible. This wasn’t the chaffiest coffee, so I had an easy time of that.
Starting off with my usual stats of full power, manual roast, and high drum speed, I pushed this coffee through drying as quickly as possible on the Behmor 1600 Plus. Again, I wanted to draw out Maillard as long as I could without stalling, so I engaged P4 (75% power) at what happened to be 40 seconds before first crack. Crack occurred at 11:00 – certainly later than usual – with lots of false pops preceding the actual rolling crack. I allowed this roast to develop for longer than usual, too, and ended the roast at 12:25 with 1:35 of post-crack development time.
On my kitchen counter/cupping table, this cup was wild! Honey, coconut, cedar, juniper, cherry, and moss came out in the break, and clean sugars came through in the tasting. This coffee not only looked and smelled like the coffees I had the opportunity to sample in Sumatra just after harvest, it tasted that way too! I highly recommend getting these coffees as fresh as possible, and this is one for the books.
This is going to be excellent as a filter drip, but I could even see the case being made for its use as espresso. Most Sumatran coffees aren’t gentle and sweet enough under pressure, but I could certainly see this coffee doing well. Unfortunately I don’t have an espresso setup at home, but if you do, I’d recommend giving it a shot!
Roast Analysis by Candice Madison
Coming into the world of specialty coffee from the United Kingdom, there was very little interaction with coffees from Sumatra, or other Asian countries, as at that time the specialty coffee industry was in its infancy, and influential individual’s prejudice against ‘different’ coffee origins, as well as different processing methods (read: natural) was rife.
The global specialty coffee industry itself is not without its own issues, including the constant regurgitation of ‘othering’ narratives that continue to plague consuming and producing countries in a plethora of ways, be it coffee itself, the origin it is from or the people who produce it.
Sumatra was an origin I was warned away from, by not-very well informed persons, who I realize now didn’t understand the nature of quality, processing, origin flavor profiles, and more. However, the more I learned about coffee, tasted more widely, and recognized the results of the processing (correct and incorrect), a whole region of coffee opened up to me.
Giling Basah (wet-hulled process) coffees have previously had the reputation of being ‘dirty’ or ‘earthy’ or ‘muddy’, but the strides made in coffee processing in this part of the world have been extensive and exponential, and the evidence of years of hard work and skilled labor have gifted us an exceptionally clean, excellent example of the very best that Sumatra has to offer. My cupping notes for this coffee, other than the descriptors, was ‘an exceptional example of processing and region’.
I roasted this week’s coffee on the Diedrich to get an idea of the profiling the coffee for production use. Looking at the green coffee, you can see the work that has gone into harvesting and production – smelling and looking fresh, undamaged beans with no mottled surfaces connoting moisture/drying issues. The S795 has the physical markers of its genetic origins which include both arabica and liberica species, the latter lending the beans a pointy look.
Looking at the curve, I’d have to admit that it was a little ‘wonky’. I made a few mistakes that I can outline here for a better result, but my, this coffee is extremely forgiving in the cup! As I expected from the metrics, this coffee is slightly above ideal for moisture, but well within specialty range, as well as higher than usual water activity (aW). The density of the bean is around average, meaning that the coffee may fight initially to take on heat, but once it does, it very much drinks it in! Without applying heat carefully before coloring and through the maillard stage, you might find this roast runs away from you.
Although acidity and floral characteristics are present in Sumatran coffees, the real prize, to me, at least, is found in the complexity of the flavors married with a deep sweetness and smooth, coating body.
As expected, this coffee spent the majority of its time in the drying phase. I started the roast at 370 degrees F, about 10 degrees higher than usual. This was to speed up the drying phase of the coffee and lessen the risk of mid-roast stalling. However, the coffee started to run away from me before I realised. I turned the gas up to 5 (approx 90%), as I usually do after the turning point/equilibrium. I should have been far less aggressive at the start of the turn with the heat. At approx 240 degrees, I turned the gas down to 4.5, and just after coloring, to 3. At the same time, I turned the airflow up to 50% from 0. A teachable moment ensued! Sometimes under-correcting can be preferable to over-correcting. Reducing the gas and introducing more ambient air to a dynamic coffee, such as this meant the rate of change start to descend rapidly, and I was headed into a stall – the very thing I tried to prevent!
I quickly closed the airflow and the roast recovered remarkably quickly. First crack started slow, but soon rumbled away at around 375 degrees F. I turned the gas down to 2, once a rolling crack was underway and opened the airflow all the way. No smokey notes for me, please!
And would I be punished or rewarded in the cup? Absolutely rewarded for all of my mistakes! The distinct bamboo note that I love and prize in Sumatran coffees was up front in the flavor profile of this roast of the Kayu Aro. Accompanying it were notes of pineapple soft serve, raisin and dark chocolate. The cherry skin acidity was a perfect foil for the complex, articulate flavors, as well as the creamy, syrupy body. A big mug of batch brew, a careful and precise pourver or a rich espresso base for the perfect cappuccino? Have at it, it will suit all!
Brew Analysis by Evan Gilman
Brewing Sumatran coffee is always an adventure. I have found that many of these coffees extract quite readily, but have a tendency to show off bitter, cholorogenic-acid forward flavors. This coffee was easy to get some tasty results from, but I wanted to try something that has worked in the past to stymie the bitter flavors of a Sumatran coffee.
My first brew was pretty standard – a 1:16 ratio of coffee to water in the Chemex, with a 20 grind on the Baratza Virtuoso. Everything went swimmingly, and my final extraction percentage was 18.46% – pretty nice, but I could have pulled a bit more from the coffee. Flavors included juniper, molasses, and chocolate fudge, with a little cherry on cooling. A very pleasant cup!
So I tried keeping everything the same while coarsening the grind a bit, to 24 on the Virtuoso. I got a nearly identical extraction (18.6%), but in a slightly shorter amount of time due to the water flowing through more quickly. The flavors here were definitely inferior, though. Molasses took the front, with some indistinct plum and cola notes on the finish. No sweet cherry notes, and a little bitterness on the finish. Wrong direction! I recommend grinding fine, and maybe even using a little dilution…
Which brings me to how I like to brew Sumatran coffees – with a little bypass. I brewed at extra high strength ( 1:9.5 ) and then diluted to 1:14.5. My first brew was only 380g of water for 40g of coffee, with 200g of bypass water added later. The result was nothing short of fantastic, and reaffirmed my love of Sumatran coffees. Lime, melon, clear palm sugar, and a syrupy black cherry (think homemade bourbon-soaked cherry) were all there. This really brought out the sweetness in the cup, and pushed those bitter notes out of the way.
Try a bypass brew for this coffee!