Introduction by Chris Kornman
Kiawamururu is the name of this coffee’s factory (washing station) accepting coffee cherry from about 600 local farming families in Nyeri county. The resulting coffee is a delicious mix of floral and fragrant hop character with loads of tart berries and stone fruits in the flavor profile.
The coffee is double washed, employing a common East African tactic of soaking the parchment coffee in clean water after fermentation. Not only does this help remove any leftover pulp on the seeds, it also triggers the seed to begin germinating and it’s speculated this can improve the flavor.
Once at the dry mill, the coffee is sorted for defects, density, and size. This lot is just the peaberries: genetic flaws, typically making up no more than about 5% of an average harvest. Typical coffee seeds split during the early stages of growth inside the cherry, forming two so-called “flat beans.” Peaberry seeds never undergo the split, and thus are completely round.
Smallholders like those that contribute to Kiawamururu tend to measure their plots by number of trees rather than acreage, averaging around 250 coffee plants per plot. Many are inter-cropping to improve the biodiversity of the region and the security of their harvest, planting banana, grevillea, and macadamia in addition to coffee. Kenya’s auction system elevates the value of exceptional coffees, and keeps the country’s coffee margins high, stable, and independent of the volatile C Market.
Like most Kenyan growing regions, coffee in Nyeri benefits from its equatorial location and two distinct annual rainy seasons, resulting in a main crop in the winter and a “fly” crop harvested in the summer. However, East Africa has been hard-hit by climate disruption in recent years, and Kenyan production is very low this year by comparison to last. Early predictions originally seemed to indicate a good year, but drought, irregular rains, and a frost in Othaya have cut yields for both main and fly crops.
Green Analysis by Chris Kornman
This peaberry is a slightly larger than average for Kenyan peaberry, though it otherwise trends normally for its type: dry in moisture, high in density. It’s not unusual to see a little wider distribution in screen size, as well, since peaberry isn’t so much a size designation as it is a distinctive shape. While often prized by roasters, particularly from Kenya and Tanzania, the size, shape, and density can cause some complications when roasting. Keep an eye on Jen’s notes for heat applications.
The lot is built on a blend of common Kenyan varieties. SL-28 and SL-34 are two of the most highly regarded varieties produced by Scott Laboratories in Kenya in the 1930s. Scott Labs no longer exists as such, but is now the National Agricultural Laboratories, a part of the larger Kenya Agricultural & Livestock Research Organization. Both varieties are Bourbon derivative cultivars, though from different lineages: SL-28 was developed from a drought-resistant variety originally cultivated in Tanganyika, a territory that makes up part of modern day Tanzania; it’s generally considered to be of the highest quality but is not very productive compared to other commercial Arabica varieties. SL-34 is a Kenyan mutation originally found near Kabete, and excels at lower elevations. Both of these SL variants exhibit bronze-tipped leaves on the newest growth.
Joining the classics are two relative newcomers. Ruiru-11 was developed in the mid-1980’s as the result of attempting to make an SL-28 more productive and resistant to Coffee Berry Disease and Leaf Rust by crossbreeding with varieties as disparate as Sudan Rume (for quality) and Catimor (for disease resistance), among others. In response to qualitative feedback, the Coffee Research Institute retraced the steps to creating Ruiru-11, attempting to improve cup quality without compromising disease resistance. Since 2010, the new variety called Batian has trickled into production, and early results are promising.
Roast Analysis by Jen Apodaca
Most peaberries are more dense than their flat bean siblings and because of that they can really take on a lot of heat. This Nyeri did exactly just that, but it also had a little help with a slightly higher water activity reading than the rest of the Kenya harvest that we have seen this year so far. This created more opportunity for sugar browning and produced a higher level of roast degree overall as evidenced by the ground colortrack sample. Compared to another Kenya peaberry, CJ1138, the same roast produced a colortrack number almost 2 points higher which is a significant difference. The increased degree of the roast rounded out the citrus notes and produced a sweet and balanced marmalade in its place. If you are looking for a bit more of a grapefruit pop, I would recommend a lower charge temperature to control your velocity through the Maillard stage.
Roast notes: Orange marmalade, cranberry, red apple, cocoa
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 have come to terms with the fact that not every roast is going to turn out the way I want it to, and have decided to learn from my mistakes by facing them head-on. This roast turned out darker than I wanted! There, I said it.
So what happened? Well, the crack on this coffee was not quite as audible as most, and I may have missed the signal that the first few pops could have given me. Keep an ear on this coffee, it’s very soft spoken. This would account for the longer amount of time the coffee remained in the roaster, about a full minute longer than most of my other roasts.
I went deep into development territory, but not completely over to the dark side. After all, one does not simply walk into second crack. My intentions were good here, and I engaged P3 at 14 minutes after I heard what I believed was first crack. All of my other parameters followed my standard recommended ones (manual full power with P5, full drum speed from the beginning of roast) – this was just a tough bean to crack.
All this being said it was still a palatable darker roast, by no means un-quaffable. Some deep blackberry, roasted tomato, sweet barbecue, and dry florals like juniper and lavender made themselves present on the cupping table. Not all was lost!
Brew Analysis by Evan Gilman
We experienced some brewing anomalies with this tasty Kenyan offering. As you can see below, these extraction parameters are nearly identical, with the variable being the grind setting on the EK43. These were both done with Jen’s first roast. Both were performed on the Chemex, and coffee was weighed both before grinding and after ground in the filter (before pouring water) to ensure consistency.
The first brew listed here had some great sweetness, but was perhaps a little savory on the finish. Mostly, we found lots of sugars, limey acidity, and some florals as well.
The second brew brought us more grapefruity acidity, complex herbal florals, and a candy-like sweetness with an incredibly clean finish. Two of the three of us preferred this brew.
What is truly curious is that I somehow achieved more dissolved solids in the brew with a coarser grind…