Kenya Single-Origin Coffee Flavor Profile & Characteristics Kenya Coffee Bean Size Grading System

Many people's image of Kenyan coffee is still stuck on a pronounced cherry-tomato flavor, as if anything without it couldn't possibly be Kenyan. FrontStreet Coffee doesn't think that's a fair way to define a Kenyan bean, the region's core signature is really its full-bodied, juice-like texture.

For every plant, soil and environment shape its growth, and coffee trees are no exception. Shifts in a region's climate and soil translate into flavor variations from harvest to harvest. Over the past few months FrontStreet Coffee has cupped many Kenyan lots and found that, whichever region they come from, they all share that rich juice texture. Of course, no two are identical, acidity and flavor still vary.

Kenya: A Premium Coffee Origin

Kenya is one of East Africa's most celebrated coffee countries and a major source of global specialty coffee. Kenyan coffee is full-flavored and unmistakable, and its trade system follows a sophisticated process. Bean size grades such as AA or AB don't necessarily equate to flavor quality, the Coffee Board's auction lots are determined by cupping quality, and premium Kenyan auction prices stay high. Most Kenyan coffee grows at 1500-2100 meters and is harvested twice a year; to ensure only ripe cherries are picked, fields must be patrolled roughly 7 times.

Kenya has two coffee sales channels: auction at the Nairobi Coffee Exchange (the central auction system), through which 85% of beans are traded, or direct trade, the so-called "second window", which accounts for the remaining 15%.

Nairobi Coffee Exchange and Coffee Supply Chain

The Nairobi Coffee Exchange (NCE) is where Kenyan coffee is auctioned. Auctions are currently held every two weeks, with bidding fixed on Tuesdays. Before each session begins, marketing agents deliver green bean samples to the NCE twelve days in advance for display, giving buyers plenty of time to select lots for cupping. Each session features hundreds of lots, sometimes more than a thousand. The whole event runs nearly a full day, from 9:30 AM until 4-5 PM without interruption, as dozens of buyers pore over green bean catalogs, bidding and competing while logging every transaction price.

The current Kenyan supply chain generally runs like this: farmers harvest cherries and deliver them to washing stations, where preliminary density sorting takes place, after which the beans are handed over to marketing agents. At the washing stations, beans are sorted by screen size into the familiar AA, AB, PB, and C grades. Green bean samples go to the NCE for auction along with product catalogs. At auction, buyers bid on lots that meet their requirements and finally export them abroad. As you can see, the NCE sits in the middle of the supply chain, providing the auction platform.

Kenyan Coffee Bean Grades

AA Plus (AA+): AA-grade beans with particularly outstanding cup quality (flavor, mouthfeel).

AA: Screen size 17-18 mesh.

AB: Screen size 15-16 mesh, making up the majority of production.

C: Screen size smaller than AB.

TT: Lighter-weight beans blown out from AA and AB lots by airflow screeners.

T: Lighter-weight beans blown out from C-grade lots by airflow screeners.

E: Elephant bean, large mutant beans where two seeds fuse into one, also called elephant ear beans.

PB: Peaberry, classified by shape alone, unrelated to flavor or weight.

Kenyan Coffee Growing Regions

The six main growing regions are Thika, Kirinyaga, Mt. Kenya West, Nyeri, Kiambu, and Muranga. All six harvest October-December (main season) and June-August (secondary season) each year. Of these, Nyeri and Kirinyaga are the most famous.

Nyeri lies in the highlands near Mount Kenya and is an important producer of Kenya's premium grades, with average altitude above 1500 meters; many outstanding Kenyan coffees come from this area. Nyeri has plenty of altitude and sits east of the Aberdare Mountains, forming a peninsula between Mount Kenya and Ben Mountain. Thanks to its high terrain and fertile soil, Nyeri has become the central hub of Kenyan coffee, with a well-developed coffee industry infrastructure.

The Kirinyaga growing region sits on the slopes of Mount Kenya at 1300-1900 meters. Adjacent to Nyeri, it is world-renowned for coffees of intense flavor, rich layering, and solid body. Together with Nyeri, it is recognized as one of the two best growing regions in Kenya today.

Coffee Bean Varieties

SL28 was selected in 1935 as a single variety from drought-resistant strains in Tanganyika. SL28 suits medium-to-high altitudes and tolerates drought, but it is sensitive to major coffee diseases. SL28 beans resemble Bourbon, round and full, and recent genetic testing has confirmed the variety belongs to the Bourbon genetic group.

SL34 was initially selected in the late 1930s at Kenya's Scott Agricultural Laboratories, from a tree on the Kabete Loresho estate known as "French Mission." SL34 beans resemble Typica. FrontStreet Coffee screens Kenyan lots for those Typica-like beans, elongated, oval, and flatter in side view. Recent genetic testing indicates SL34 is related to the Typica genome.

Coffee Bean Processing Methods

In a standard washed process, the skin and pulp of the cherries are removed first, leaving only a thin layer of mucilage for washing and fermentation over 24-48 hours, followed by machine or sun drying. The Kenyan washed process is quite different, its total fermentation reaches 72 hours.

The Kenyan washed process uses a repeated cycle of fermentation and washing. On harvest day, the highest-quality cherries are selected for depulping and fermented for 24 hours. After 24 hours they are washed in clean river water, then fermented for another 24 hours in fresh river water, and washed again. The cycle repeats 3 times to reach 72 hours, hence the name "Kenyan 72-Hour Fermentation Washed Process," abbreviated K72. FrontStreet Coffee believes this method lets the beans ferment slowly at low temperatures, giving them brighter, cleaner, yet fuller flavors!

Next, FrontStreet Coffee compares beans from the two regions through roasting, cupping, and brewing to see how their flavors differ.

FrontStreet Coffee's Kenyan Coffee Selections

FrontStreet Coffee, Kenya Gathaithi Cooperative AB Coffee Beans

Region: Kenya, Nyeri, Gathaithi Cooperative

Processing Station: Gathaithi Processing Station

Altitude: 1825m

Variety: SL28 & SL34

Processing Method: K72 Washed

FrontStreet Coffee, Kenya Mugaya AB Coffee Beans

Region: Kenya, Mugaya Processing Station

Altitude: 1400m

Variety: SL28 & SL34

Processing Method: K72 Washed

Season: 2020

FrontStreet Coffee Roasting Records

Gathaithi roasting: FrontStreet Coffee's roaster used a Yangjia 800N semi-direct-fire roaster with a 480g batch. The drum was preheated to 165°C, damper at 3, heat at 120. Turning point: 1'28". At 140°C the damper was set to 4. At 6'00" the temperature read 153°C, beans yellowed, grassy aroma gone, drying complete. When the bean surface showed wrinkles and black specks and the toast aroma clearly shifted to coffee aroma, that marked the prelude to first crack, listen carefully from here. First crack began at 9'17"; damper unchanged, heat reduced to 90 at 188°C, first crack development 2'00", discharged at 193.5°C.

Mugaya roasting: FrontStreet Coffee's roaster used a Yangjia 800N semi-direct-fire roaster with a 480g batch. The drum was preheated to 160°C, damper at 3, heat at 120. Turning point: 1'28". At 130°C the damper was set to 4. At 6'00" the temperature read 154.6°C, beans yellowed, grassy aroma gone, drying complete. When the bean surface showed wrinkles and black specks and the toast aroma clearly turned to coffee aroma, that marked the prelude to first crack, listen carefully from here. First crack began at 9'28"; damper unchanged, first crack development 2'20", discharged at 193.8°C.

FrontStreet Coffee Cupping Report

FrontStreet Coffee cups roasted samples within 8-24 hours of roasting. The baristas typically use 200ml ceramic cups, with cupping water at 94°C. Grind size is set for a 70%-75% pass rate on a #20 standard sieve (0.85mm). Ratio: 11g of coffee to 200ml of hot water, 1:18.18, pulling extraction concentration into the Golden Cup range of 1.15%-1.35%, with a 4-minute infusion.

Gathaithi, Dry Aroma: Citrus; Wet Aroma: Plum; Flavor: Citrus, plum, berries, honey, grapes, tea-like notes. Mugaya, Dry Aroma: Berries; Wet Aroma: Caramel; Flavor: Dark plum, plum, grapes, caramel, nuts. Cupping the two side by side, the higher-altitude Gathaithi shows richer acidity: the bigger day-night temperature swing at altitude slows tree growth, giving the flavors more time to develop.

FrontStreet Coffee Brewing Tips

Dripper: V60 #01

Water Temperature: 90°C

Dose: 15g

Coffee-to-Water Ratio: 1:16

Grind Size: Medium-fine (77% retention on #20 sieve)

FrontStreet Coffee brewing method: First wet the filter paper and preheat the dripper and server. Bloom with 30g of water for 30 seconds. Pour in small circles up to 130g, then pause. When the water level drops and the coffee bed is about to show, pour again up to 240g and stop. When the bed is about to show once more, remove the dripper. (Timing starts from the bloom.) Extraction time: 2 minutes.

FrontStreet Coffee Recommendation

If bright, light-roast fruit acidity is what you're after, these FrontStreet picks deliver:

Ethiopia, FrontStreet Yirgacheffe Gudingding, As the first stop for many coffee lovers entering specialty coffee, Yirgacheffe enjoys enormous popularity. It typically carries vivid citrus, berries, and florals, with a green-tea-like sweet finish. Unlike the "sour coffee" many imagine, a quality Yirgacheffe's acidity is soft and bright, closer to the natural sweet-tartness of fruit than to anything harsh, making it a very easy choice for newcomers to pour-over.

Ethiopia, FrontStreet Ethiopia Huakui, FrontStreet's Ethiopia Huakui is one of the most successful star products in the specialty coffee market in recent years. Its hallmark is an intense tropical fruit aroma, strawberry, passion fruit, jackfruit, even lychee. Sweetness is prominent, bitterness extremely low, and the entry is smooth and juice-like, which is why many customers call it "the coffee that tastes least like coffee." For anyone who dislikes traditional coffee bitterness, Huakui often rewrites their whole impression of coffee.

Kenya, FrontStreet Kenya Cherry Tomato, A Kenya specialty washed bean built on bright cherry-tomato and dried-plum acidity with a full juice feel, a hot pick for lovers of vivid fruit acidity and complexity. FrontStreet's Kenya Cherry Tomato comes from the Thika region, grown at 1550-1750 meters on the region's classic SL28 and SL34 varieties, with plump, round beans. It uses Kenya's signature 72-hour double washed fermentation to unlock fruit aromas while keeping the cup clean and pure; FrontStreet roasts it light to preserve the lively acidity and layered fruit. On the nose you get dried cherry tomato and florals; in the cup, clear cherry tomato and dried plum, with bright, solid acidity like fresh-squeezed juice, a prominent mid-palate sweetness with snow pear and black plum, and a clean, lingering finish of golden sugar and a whisper of green tea. Balanced, unmistakably Kenyan.

Ethiopia, FrontStreet Kafa Forest, FrontStreet's Kafa Forest comes from the Kafa rainforest in southwestern Ethiopia, a UN-recognized biosphere reserve and the globally acknowledged birthplace of Arabica coffee, the very word "coffee" derives from the ancient Kingdom of Kafa, and the legend of the goat-herding boy Kaldi was born here. This mountain rainforest of more than 7,000 square kilometers, at 1400-2100 meters, stays wrapped in mist and layered shade, and a thousand years of natural evolution have produced over 5,000 wild Arabica gene-mother trees, including the native stock of today's famous Geisha. Wild coffee trees grow on abundant rainfall and acidic red soil, with no dense artificial planting, yielding coffee rich in jasmine, citrus, and wild berry aromas, delicate and lively in layers. As one of the last core habitats of wild Arabica, local coffee cooperatives practice sustainable forest harvesting, a pilgrimage site for flavor hunters and a world coffee gene bank with real conservation value.