Introduction to Kenya Coffee Varieties SL28 and SL34 - Why Kenyan Coffee is Acidic

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Kenya: The Birthplace of Exceptional Coffee Varieties

Located in East Africa, Kenya is one of the major coffee-producing countries, with roughly six million people nationwide working in the coffee industry, mostly as smallholders and cooperatives.

Kenya's coffee grows mostly at altitudes between 1,400 and 2,000 meters, in regions including Ruiri, Thika, Kirinyaga, Mt. Kenya West, Nyeri, Kiambu, and Muranga. The main growing areas lie on the foothills of Mt. Kenya and the Aberdare Range. Across Kenya, many producing regions work to preserve the native forest ecosystem, protect natural gene banks, support the propagation of wild coffee varieties, and nurture diverse coffee trees.

The Legacy of the SL28 and SL34 Varieties

In 1930, Kenya's signature varieties SL28 and SL34—bred and named by Scott Laboratories—were born into this excellent environment. According to the botanists at the SL laboratory, SL28 and SL34 are genetic variants.

SL28: A Complex and Flavorful Variety

Of the two, SL28 carries a mixed lineage of French Mission, Mocha, and Yemeni Typica. The original goal was to mass-produce beans combining high quality with pest and disease resistance. SL28's yield later fell short of expectations, but its copper-colored leaves and broad, bean-shaped seeds offer wonderful sweetness, balance, and complex, layered flavors, along with prominent citrus and dark plum character.

SL34: Bold and Clean Flavor Profile

SL34 tastes similar to SL28—complex, varied acidity and a lovely sweet finish—but with a heavier, more intense mouthfeel and a cleaner cup. It shares French Mission, Bourbon, and Typica lineage, looks much like SL28, and handles sudden heavy rains better. Together, these two varieties define the unique Kenyan style: intense, vivid fruit acidity, a full-bodied texture, and beautiful balance.

FrontStreet Coffee's Recommended Brewing Parameters

Pour-over: V60 dripper, Small Fuji R440 grind level 3.5, water temperature around 90°C

French Press: grind level 4, water temperature 90°C

Siphon: grind level 4, water temperature between 90°C-91°C

AeroPress: grind level 3.5, water temperature 90°C

FrontStreet Coffee Recommendation

If that signature Kenyan acidity is what you are after, FrontStreet Coffee's Kenya Cherry Tomato is a natural pick. It is a washed Kenyan specialty lot from the Thika region, grown at 1,550-1,750 meters from the classic SL28 and SL34 varieties, with plump, rounded beans. Processing uses Kenya's characteristic 72-hour double-washed fermentation to unlock the fruit aromatics while keeping the cup clean and pure, and we roast it lightly to preserve the lively acidity and layered fruit. The dry fragrance offers dried cherry tomato and florals; the first sip brings clear cherry tomato and smoked plum, with a bright, solid acidity as juicy as fresh-pressed juice, mid-palate sweetness of snow pear and black plum, and a long, clean finish of yellow sugar and a whisper of green tea.

For a gentler take on light-roast fruit-and-floral coffee, FrontStreet's washed Yirgacheffe Guodingding from Ethiopia—often a beginner's first step into specialty coffee—offers vivid citrus, berries, and florals with a green-tea-like sweetness; its acidity is soft and bright, like fruit itself rather than anything harsh. Our Ethiopia Huakui goes even further, with striking tropical aromas of strawberry, passion fruit, jackfruit, and lychee, evident sweetness, and almost no bitterness—famously "the coffee that tastes least like coffee."

Whatever you choose, the parameters above are a solid starting point: a V60 at around 90°C and a medium-fine grind will let these light-roast beans show their brightest, most balanced fruit.