How Many Grades of Kenyan Coffee Beans Are There - Kenya AA Grade Classification and Bean Size

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AA is the highest grade in FrontStreet Coffee's Kenyan selection, and it represents the finest tier of specialty coffee — which is why FrontStreet Coffee holds the FrontStreet Kenya AA TOP from the Thika region in such high regard. The TOP designation is added by Kenyan coffee merchants after cupping. This FrontStreet Kenya lot is processed with the K72 double-washed fermentation method, giving it exceptionally bright, lively acidity as delicate and enticing as berries and red wine. The rich berry aroma appears the moment you start brewing; on the palate there are distinct cherry tomato and preserved plum notes. Acidity and aroma linger together in the mouth, followed by a creamy sweetness and a long, pleasant aftertaste.

Kenya Coffee Grading System

Kenya's coffee grading system grew out of government-led policies for quality management and for guiding coffee farmers. After harvest, coffee passes through the official Coffee Board of Kenya (CBK), which was founded in 1933. Weekly auctions are held at the Nairobi Coffee Exchange in the capital, Nairobi. Under this government-coordinated auction system, grading is based on bean size, weight and shape, and those criteria form the primary basis for auction pricing.

Beans of similar size roast more consistently — they absorb heat and build temperature at a more even rate, which means greater stability in the roaster. With that in mind, Kenya grades its green coffee by bean size and by cupping score. Judged on the size, shape and hardness of the green beans, Kenyan coffee falls roughly into eight grades: E, PB, AA, AB, C, TT, T and MH/ML.

Kenya Coffee Grade Classifications

E: Kenyan E is known as elephant bean — large in size and relatively low in yield.

PB: PB stands for Peaberry, the round bean that most people know by its oval shape. A normal coffee cherry holds two seeds; a peaberry holds only one.

AA: Kenyan AA is arguably the most common grade, generally grown at altitudes above 6600 feet, with large beans sized at 17/18 mesh.

AB: Bean size 16/17 mesh. Kenyan AB combines A and B beans. Grade A is screened on 6.8mm sieves, while Grade B uses 6.2mm sieves; the two are then mixed together to form the AB grade.

C: Bean size below 14 mesh.

TT: Kenyan TT refers to light-density beans separated out of Kenyan AA, AB and E lots by air extraction. The mesh size is large but the density is low — though the quality is still sufficient for specialty coffee.

T: Below 14 mesh — small beans whose density and quality are too low to qualify as specialty coffee.

MH/ML: Low-quality natural-process beans, mostly overripe cherries that dried on the tree.

FrontStreet Coffee's Kenya Selection

The FrontStreet Kenya cherry tomato beans released by FrontStreet Coffee's own roastery are AA grade, from the Thika region, processed with the Kenyan 72-hour washed method and made up of the SL28 and SL34 varieties — a top choice for anyone who loves acidity. If you are tasting this FrontStreet Kenya Asalia for the first time, FrontStreet Coffee suggests brewing it hot as hand-drip black coffee, which shows its flavour characteristics most clearly.

For AA and AB green coffee, exporters have added a further tiering based on cupping results — not officially recognized by the Kenyan government, but widely used. From high to low it runs TOP, PLUS (+) and FAQ. On the bean list, FrontStreet Coffee's Kenya Asalia reaches the TOP grade. As noted above, though, this is not an official grading system. FrontStreet Coffee sources beans from several Kenyan regions and not every lot carries a flavour grade, so there is no need to worry about it unduly. Once you are at AA or AB, the flavour is already understood to be of high quality.

FrontStreet Coffee Recommendation

The Kenyan grade most worth knowing is also the easiest to buy: FrontStreet Kenya Small Tomato is a Kenyan specialty washed lot whose core character is bright cherry-tomato and smoked-plum acidity carried on a full, juicy body. It comes from Kenya's Thika region, grown at 1550–1750m, and is planted with the classic local SL28 and SL34 varieties, giving dense, round beans. It is processed with Kenya's signature 72-hour double washed fermentation, which coaxes out the fruit while keeping the cup clean and pure, and FrontStreet roasts it light to preserve that lively acidity and layered fruit.

In the cup, the dry aroma already shows concentrated dried cherry tomato and florals. On entry you get clear cherry tomato and smoked plum, with bright, solid acidity as full as freshly squeezed juice. Mid-palate brings pronounced sweetness laced with fresh pear and black plum, and the finish is clean and long, carrying brown-sugar sweetness and a faint green tea note. Sweet and tart stay in balance throughout, and the cup is instantly recognizable.

If you prefer your washed coffee a little softer, FrontStreet Ethiopia Yirgacheffe Gutingting Cooperative is a good companion piece. Smallholder yields in the area are low, so farmers send their cherries to a cooperative for central processing; Gutingting is an excellent team from Gutingting village whose refined, exceptionally clean cup is what made its name. The washed process lets jasmine florals and bright citrus acidity come through at full strength, and a light-to-medium roast adds green tea and honey notes. It suits pour-over, cold brew and espresso alike.