Kenya Africa Coffee Bean Flavor Profile Introduction What to Do with Kenya AA Grade Coffee Being Too Sour

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When it comes to coffee bean regions with distinct acidity, coffee enthusiasts might think of Ethiopia. However, beyond Ethiopia's citrus and lemon acidity, neighboring Kenya's coffee beans with their black plum and cherry tomato acidity are also beloved by FrontStreet Coffee enthusiasts. Although Kenya's coffee development started later than Ethiopia's, it has leaped into the specialty coffee market with its exquisite washed processing technology and coffee beans featuring pleasant acidity. FrontStreet Coffee's article will now discuss the acidity of Kenyan coffee.

Why Kenyan Coffee Beans Are Acidic

Coffee enthusiasts all know that among the three major coffee growing regions, African coffee beans are famous for their acidity. Kenya is located in eastern Africa, bordering Ethiopia, but their acidity expressions are completely different. Kenya's coffee history began in the early 20th century when introduced by British colonizers. Although starting late, under colonial rule, both coffee cultivation mechanisms and the establishment of grading systems laid the foundation for Kenyan coffee to enter the specialty market and enjoy world-renowned status.

So why does Kenyan coffee have pleasant acidity? FrontStreet Coffee believes it's closely related to the local exquisite washed processing technology. Because washed processing itself can highlight the original flavors of coffee beans, remove impurities, and make the flavor expression brighter and cleaner. For example, the famous Jamaican Blue Mountain coffee has always dominated the coffee market with its washed Blue Mountain coffee, capturing coffee enthusiasts' hearts. However, Kenya's washed processing method takes this a level higher, known as the K72 washed processing method.

Kenyan K72 Washed Processing Method

Kenyan-style washed processing involves a cyclic repeated treatment of washing and cleaning after coffee cherry fermentation. First, coffee farmers harvest and select the highest quality coffee cherries, then remove the peel and ferment for 24 hours. After 24 hours, they wash with clean river water. Then they ferment again in clean river water for 24 hours, then wash again, repeating this cycle 3 times to reach 72 hours. This is why it's called Kenyan-style 72-hour fermented washed processing method, abbreviated as K72. This processing method allows coffee beans to ferment for a long time at low temperatures, giving the beans brighter, cleaner, yet fuller flavors.

Kenyan Coffee Bean Varieties

Additionally, Kenyan coffee bean varieties contribute to the excellent acidity of Kenyan coffee beans. FrontStreet Coffee's previous articles mentioned that the three major factors affecting coffee bean flavor are growing region, variety, and processing method. Kenyan coffee beans mainly come from hybridization of Ethiopian native varieties and Bourbon varieties, called SL28 and SL34. The main varieties cultivated in Kenya are SL-28, SL-34, Ruiru 11, and Batian.

SL-28, SL-34

SL actually stands for Scott Labs, Scott Laboratories. In the 1930s, Scott Laboratories was commissioned by the Kenyan government to conduct research on coffee breeding and classification, attempting to find varieties that could adapt to Kenya's terroir, be suitable for large-scale cultivation, and have commercial value. SL-28 and SL-34 were two of the many research results. This organization was active from the 1930s to 1960s but no longer exists.

The SL series was developed based on research and selection from Yemen Mocha ancient varieties and Bourbon from Réunion Island. Today, they account for the majority of Kenya's coffee production. Relatively speaking, SL-28 has gained higher recognition, while SL-34 has higher yields and is grown at slightly lower altitudes.

According to SL laboratory botanists, SL28 and SL34 are genetic variants. Among them, SL28 has mixed heritage from Mocha and Yemen Typica. The original goal of cultivating SL28 was to mass-produce coffee beans that combined high quality with disease and pest resistance.

Although SL28's yields didn't meet the massive expectations, it has been passed down to this day because of its copper-colored leaves, broad bean-shaped beans, wonderful sweetness, balance, complex and varied flavors, and significant citrus and black plum characteristics. This is also the main reason why Kenyan coffee is rich in pleasant acidity.

SL34 has similar flavors to SL28 - besides complex and varied acidity and wonderful sweet finish, its body is heavier, richer, and cleaner than SL28. SL34 has Bourbon and more Typica heritage. The bean appearance is similar to SL28, but it's more resilient, for example, adapting to sudden heavy rain.

Ruiru 11

Ruiru appeared after SL28 and SL34. According to FrontStreet Coffee's understanding, in the 1970s, Ruiru station began experimenting with cultivating different CBD and rust-resistant varieties. The result was Ruiru 11, released in the 1980s. High yield with CBD and rust resistance properties seemed to be the solution to all of Kenya's coffee production problems.

Batian

The Batian variety was launched by the Coffee Research Institute (CRI) on September 8, 2010. It's also the newest variety offered by Kenya. It was a further experiment based on lessons learned from Ruiru 11. Genetically, it was essentially selected from backcrosses of SL28 and SL34, making it closer to SL28 than Ruiru 11. This also eliminated problematic Robusta coffee bean elements, thereby improving cup quality.

The Impact of Roast Degree on Kenyan Coffee Bean Acidity

As FrontStreet Coffee mentioned above, the strength of coffee acidity is related to coffee variety and processing method, and secondly to the country's soil, climate, and altitude. Coffee contains acidity because coffee beans fully absorb the fruit acids from the pulp during growth and processing. In terms of varieties, high-quality Arabica coffee beans are more acidic, so Blue Mountain, Kenya, Guatemala, Mocha, Costa Rica, and other coffees all have some fruit acidity. Robusta coffee beans, which are easier to cultivate and cheaper, have almost no acidity.

But beyond this, coffee roast degree can also greatly affect coffee acidity. According to FrontStreet Coffee's roaster's practice, lightly roasted Kenyan coffee beans have a pH between 4.5-4.7, medium-dark roast coffee has a pH around 5-5.5, and dark roast has a pH above 5.5. For ordinary taste buds, if a drink's pH exceeds 5.5, it's difficult to detect its sour taste, so heavy dark roast beans are less likely to taste acidic.

Therefore, the roast degree also controls the 'bitterness' and 'acidity' of coffee. The darker the roast, the lower the acidity, and bitterness increases accordingly. However, as roasting deepens, the original characteristics of coffee beans gradually decrease due to increased carbonization, so dark roasting is not suitable for coffees with obvious acidity. This is why FrontStreet Coffee's African region coffees are almost all lightly roasted.

So FrontStreet Coffee suggests that those who like tangy and flavor-changing coffee should consider lightly roasted African and Central American beans, such as Kenya, Ethiopia, Yemen Mocha, Guatemala, Costa Rica, etc., all of which are excellent acidic coffee beans. Those who prefer rich, aromatic, and sweet coffee can choose Asian dark roast beans, such as Indonesian Mandheling, Brazilian Queen Estate, both are good choices.

The above is FrontStreet Coffee's summary of where Kenyan coffee bean acidity comes from. Next, FrontStreet Coffee will share FrontStreet Coffee's news and roasting/brewing data about Kenyan coffee beans.

FrontStreet Coffee Kenya Asalia Coffee Beans

Country: Kenya
Region: Asali (Honey Processing Station)
Altitude: 1550-1750m
Variety: SL28, SL34
Processing: 72-hour washed processing
Flavor: Snow pear, black plum, brown sugar, cherry tomato, plum

FrontStreet Coffee Kenya Thagini Estate PB Coffee Beans

Country: Kenya
Region: Thagini Estate
Altitude: 1680m
Variety: SL28, SL24, Ruiru
Processing: 72-hour washed processing
Flavor: Cherry tomato, almond, black plum, honey, grape

FrontStreet Coffee Roasting Analysis

For this roast, FrontStreet Coffee chose Kenya Thagini coffee beans. This dense coffee bean has high altitude and relatively hard beans. We started with a higher temperature rise, with yellowing at about 5 minutes, then reduced the heat to enter the Maillard reaction, and again reduced the heat at 166°C to extend the Maillard reaction time. When the first crack begins, endothermic reaction is strong, so it's recommended to maintain heat at this stage to prevent stalling. First crack development takes more time, helping to reduce acidity and develop flavors.

Roaster: Yangjia 800N (300g batch size)

Charge temperature: 170°C, heat 100%, damper 3; Return point at 1'42", when temperature reaches 140°C, open damper to 3.5, heat unchanged; At 149°C, bean surface turns yellow, grassy smell completely disappears, entering dehydration stage;

7'14" dehydration complete, heat and damper unchanged; At 7'30", bean surface shows wrinkles and black patterns, toast aroma turns to coffee aroma, prelude to first crack, pay attention to listen for first crack sound. At 8'20" first crack begins, open damper to 4, reduce heat to 50. Post-first crack development time 1'50", reduce heat to 30 at 188°C, flatten temperature rise, discharge at 193.3°C.

FrontStreet Coffee Brewing Suggestions

Dripper: V60 or flat-bottom dripper
Water temperature: 88-90°C
Coffee-to-water ratio: 1:15
Grind size: Fine grind (Chinese standard 20-mesh sieve 80% pass-through)

Brewing method: Pour-over in stages. Use 30g of water for 30-second bloom, continue pour-over in small circles to 124g, then segment. When water level drops and is about to expose the coffee bed, continue pouring to 228g and stop. When water level drops and is about to expose the coffee bed, remove the dripper (timing starts from bloom). Extraction time: 1'55".

When brewing with V60, it smells floral, with cherry tomato, citrus, and nutty acidity at entry, cream aroma in the middle, brown sugar sweet finish, with cocoa and oolong tea aftertaste. Flavor layers are rich, with obvious floral aroma; When brewing with flat-bottom dripper, it smells of herbal plant and cherry tomato aroma, overall juice sensation is obvious, acidity is more lively.

For more specialty coffee beans, please add FrontStreet Coffee's private WeChat: kaixinguoguo0925

Important Notice :

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FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473