Premium Kenyan Coffee: Introduction to Kenyan AA Grade Premium Coffee Beans and Characteristics of Kenyan Black Coffee

Kenya Coffee: A Comprehensive Guide to East Africa's Premium Coffee

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Coffee growing regions are primarily located between the Tropics of Cancer and Capricorn. FrontStreet Coffee will provide a general overview of world coffee distribution characteristics. Internationally, coffee is mainly cultivated in Africa, Central America, and Asia. Asian coffees typically feature herbaceous and spicy notes, American coffees are known for nutty and balanced flavors, while African coffees generally display fruity acidity.

Africa has always been one of the world's finest coffee origins, renowned globally for captivating acidity and aroma. Kenya certainly doesn't disappoint in this regard. Located in East Africa, precisely on the equator, with the Indian Ocean to the east, Ethiopia to the north, and Tanzania to the south, Kenya stands as East Africa's coffee powerhouse and one of the most important and irreplaceable producing countries. FrontStreet Coffee believes that a coffee bean's flavor is inseparably linked to its origin, altitude, climate, processing method, and variety. Today, FrontStreet Coffee will provide a detailed explanation of Kenyan coffee.

Kenya Coffee Origin Introduction

Kenya, officially the Republic of Kenya, is located in eastern Africa, with the equator crossing through its center and the East African Rift Valley running north-south. It borders Somalia to the east, Tanzania to the south, Uganda to the west, Ethiopia and Sudan to the north, and the Indian Ocean to the southeast. The country is characterized by high plateaus with an average elevation of 1,500 meters. Mount Kirinyaga (Mount Kenya) in central Kenya reaches 5,199 meters and has snow on its summit, making it the second-highest peak in Africa.

Altitude, Latitude, and Geology

The equator runs through Kenya, placing the country within 10 degrees north and south latitude. This tropical region experiences two rainy seasons annually, allowing for two harvests: 60% concentrated between October and December, and the remaining 40% between June and August. Coffee is primarily grown in volcanic soils at altitudes of 1,600-2,100 meters around the capital Nairobi and the Kenya mountain region. This altitude is ideal for coffee flavor development as mountain temperatures are lower, slowing growth and allowing aromatic compounds to fully develop, resulting in more pronounced fruit acidity and harder bean density. This crescent-shaped, fertile coffee zone is the primary source of Kenya's premium coffee beans.

Coffee is Kenya's second-largest export product after tea. Kenya primarily produces Arabica coffee beans, considered one of the world's highest-quality coffee varieties. African coffee origins are known for captivating acidity and aroma, and Kenya certainly doesn't disappoint. Located in East Africa, precisely on the equator, with the Indian Ocean to the east, Ethiopia to the north, and Tanzania to the south, Kenya stands as East Africa's coffee powerhouse and one of the most important and irreplaceable producing countries.

Kenya belongs to the tropical region with two rainy seasons annually, allowing for two harvests: 60% concentrated between October and December, and the remaining 40% between June and August. Coffee is primarily grown in volcanic soils at altitudes of 1,600-2,100 meters around the capital Nairobi and the Kenya mountain region. This altitude is ideal for coffee flavor development as mountain temperatures are lower, slowing growth and allowing aromatic compounds to fully develop, resulting in more pronounced fruit acidity and harder bean density. This crescent-shaped, fertile coffee zone is the primary source of Kenya's premium coffee beans.

Kenya Coffee History

In 1878, the British introduced coffee to Africa, establishing coffee plantations in Kenya during the 19th century. At that time, Ethiopian coffee beverages were imported to Kenya via South Yemen. However, it wasn't until the early 20th century that Bourbon coffee trees were introduced to Kenya by the St. Austin Mission. After Kenya's independence in 1964, the coffee industry continued to develop on its existing foundation. Today, Kenya is a world-renowned high-quality coffee-producing country. Notably, they established an auction system that successfully overcame the exploitation of small farmers common in other coffee-producing countries (this is where so-called "fair trade coffee" originated).

Kenya Coffee Varieties

In Kenya, common varieties include SL28, SL34, French Mission Bourbon, and Ruiru 11.

Origin of SL28 Variety

According to historical records, in 1931, officials from Scott Laboratories conducted field research in Tanganyika (now Tanzania). They noticed a coffee tree variety in the Moduli region that appeared to have resistance to drought, diseases, and pests. They collected seeds and brought them back to Scott Laboratories. In 1935, the laboratory selected a single tree from the drought-resistant population in Tanganyika and continuously improved it through breeding, ultimately releasing SL28 as a descendant of the Moduli variety. Recent genetic studies have confirmed that SL28 belongs to the Bourbon genetic group.

Characteristics of SL28 Variety

The SL28 variety is easy to cultivate without special care, produces large beans with high yields, and offers excellent cup quality. After being released by Kenyan authorities in the 1930s, it was first planted in Kenya before spreading to Uganda. Currently, it has gained significant attention even in Central America. This variety is suitable for medium to high-altitude regions and has drought resistance, though it remains susceptible to major coffee diseases.

Coffee Flavor of SL28 Variety

The flavor of SL28 variety indeed carries the bright acidity of original Bourbon, even the rich acidity of original Mocha varieties, along with other complex flavors and rich texture. Although SL28's yield later didn't meet expectations, its copper-colored leaves and fava bean-shaped beans offer wonderful sweetness, balance, and complex, varied flavors, along with distinctive citrus and dark plum characteristics, strong, rich fruit acidity, full body, and beautiful balance. Most notably, only when grown in Kenya can SL28 achieve this distinctive character; SL28 varieties grown in other countries only have similar flavors.

FrontStreet Coffee: Kenya Asali Coffee

Origin: Thika, Kenya

Processing Station: Asali Honey Processing Station

Altitude: 1,550-1,750 meters

Grade: AA TOP

Variety: SL28, SL34

Processing Method: Kenya 72-hour washed

Roasting Suggestions

This bean has a full, round body. To fully express its bright, rich acidity, use light roasting.

Machine: Yangjia 800N, 550g green beans

Entry Temperature: 200°C

First Crack: 5'30", 154.3°C

Development after First Crack: 2'10", discharged at 191.6°C

Brewing Suggestions

Filter: Hario V60

Water Temperature: 90°C

Dose: 15 grams

Ratio: 1:15

Grind Size: Medium-fine grind (EK43s setting 10)

Brewing Technique

Segmented Extraction

Bloom with 30g of water for 30 seconds. Using a small stream, pour in a circular motion to 125g, then segment. When the water level drops and is about to expose the coffee bed, continue pouring to 225g and stop. When the water level drops and is about to expose the coffee bed, remove the filter cup. Extraction time is 2 minutes (timing starts from the beginning of bloom).

FrontStreet Coffee Kenya Coffee Flavor Description

The wet aroma presents ripe tomato and floral notes. The entry reveals cherry tomato and dark plum flavors, with bright acidity, clean taste, and a solid, rich body like the weight of an African elephant! The mid-section features prominent sweetness with a juice-like texture. The aftertaste carries berry fruitiness and brown sugar sweetness, along with green tea aromatics.

Kenya Coffee Grading

Kenya coffee beans have adopted a strict grading system since the 1930s, primarily based on bean size, shape, and hardness. From highest to lowest, they are graded as AA or AA+, AB, PB, C, E, TT, and T. This serves as a basis for selection, with coffee flavor also used as reference. Currently, the most common grades in the mass market are AA, AB, and PB.

E (Elephant Beans): Here "E" represents "Elephant," but this doesn't refer to the elephant bean variety among coffee bean types. Instead, it's a defect caused by abnormal development where two seeds intertwine, forming what appears to be a single bean. Normally, a coffee fruit contains two seeds facing each other, resulting in one flat side (called flat beans, mother beans, or twin beans). E-grade beans are two seeds that fused together during growth, becoming oversized beans. E-grade beans are typically 18 screen (one screen equals 1/64 inch) or larger and are rare.

AA: This grade typically falls between 17-18 screen (approximately 6.7-7.1mm). It's the most commonly heard Kenya coffee grading, and in specialty coffee, this grade is usually called AA TOP. It's also the bean that most coffee shops promote, but AA doesn't necessarily mean the best—this only indicates bean size and shouldn't be confused with flavor.

AB: Most coffee beans fall into this grade. It's called AB mainly because A-grade filter holes are 6.80mm while B-grade is 6.20mm. These two sizes (A-grade and B-grade) are mixed together for sale, hence the name AB. Size is approximately 15-16 screen (about 6.0-6.4mm).

C: This grade falls between approximately 14-15 screen (about 5.6-6.0mm), smaller than B-grade.

PB: Called Peaberry in English, in Taiwan it's mostly called small round beans, but can also be called male beans or single beans. Compared to regular flat beans, this is also rare, accounting for about 10% of all coffee beans. This occurs when only one seed develops inside the fruit, resulting in a small, round bean. Some people particularly love PB flavor, so they are sorted and sold separately.

TT: These are light beans selected from AA and AB grades using air separators. They are typically light in weight, don't meet hardness standards, and may include broken and defective beans.

T: These are lighter beans selected from C-grade beans, mixed with damaged beans, and even fragments of broken beans.

MH/ML: These coffee beans are not exported and are usually overripe beans that have fallen to the ground with poor quality. They account for about 7% of all coffee beans and are only for Kenya's domestic market.

Kenya Coffee Grading - Where Do AA TOP and AB TOP Come From?

Actually, besides the official version of Kenya coffee grading, Kenyan exporters or traders have created special (unofficial) grades for AA and AB. Common ones include: AA TOP, AA+, AA++, AB+, AB TOP, and AA FAQ.

FAQ stands for "Fair Average Quality," meaning average fair quality and representing the basic AA grade. However, classifications like AA TOP, AB TOP, and AA+ don't have specific standards. Why is this?

The main reason is that these aren't unified standards. Each green bean trader or different person may produce different results. It's possible that Company A's AA+ has equivalent flavor to Company B's AA++. Therefore, everything ultimately comes back to cupping during your own roasting—that's the most practical approach!

Kenya Processing Methods

Just as honey processing is associated with Costa Rica and wet-hulling with Indonesia, when discussing Kenya coffee, how can we not mention the K72 processing method?

Kenyan-style 72-Hour Fermentation Washed Processing Method

Originating in Kenya, this method involves repeated cycles of fermentation followed by washing. Processing begins on the harvest day by selecting the highest quality cherries for pulping and fermentation. The fermentation time is 24 hours, after which the beans are washed with clean river water. Then, they undergo another 24-hour fermentation in clean river water, followed by washing again. This process is repeated for 3 cycles, totaling 72 hours, hence the name Kenyan-style 72-hour fermentation washed processing method, abbreviated as K72.

First Wash and Fermentation

After coffee cherries are harvested, they first undergo water density sorting. The principle uses the density and quality differences of coffee fruits for selection; high-density (heavy) coffee beans sink in water, while low-density beans float. Fully ripe, high-quality coffee fruits have high density, allowing them to be selected for further processing.

After selecting high-quality, sufficiently ripe fruits, the pulp is removed and the beans are soaked in water for washing. This allows the mucilage attached to the outer layer of the green beans to ferment. Mucilage contains natural sugars and alcohols that play crucial roles in developing the coffee's sweetness, acidity, and overall flavor. The fermentation time lasts 24 hours, after which 80-90% of the mucilage is removed, leaving only the flavor within the coffee beans.

Second Wash and Fermentation

Next comes the second washing and fermentation process. After the coffee beans from the previous stage are cleaned, they are soaked again in water for 24-48 hours. This process increases proteins and amino acids, creating complex and delicate layers in the coffee's acidity. Finally, all remaining mucilage is removed, and the coffee beans are moved to raised racks for sun drying.

The fermentation time lasts 24 hours, after which 80-90% of the mucilage is removed, leaving only the flavor within the coffee beans.

Finally, all remaining mucilage is removed, and the coffee beans are moved to raised racks for sun drying. The drying time varies depending on weather conditions, generally taking 5-10 days to complete.

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