Kamavindi - Theri SL28 - SL34 AA Fully Washed

Origin: Kenya - Muranga Farm: Theri - Kahuro Altitude: 1850 m Variety: SL28 - SL34 AA Process: Fully Washed This is our first year working with the Mbature family, who run Kamavindi Estate. A third-generation family operation, they have established themselves as one of the most detail-driven producers in Kenya, with a long-standing focus on precision in processing. We secured two lots this season through their operation, sourced from the Murang’a region. The Mbature family maintains a close involvement throughout, bringing a high level of consistency and intent to the coffees they handle. Kenyan coffees are classified by size. AA beans are the largest size. AA grade coffees are those that are 17/18 screen size, meaning that they are larger than 7.2 millimeters. SL28 and SL34 are varieties released by Scott Agricultural Laboratories in Kenya in the 1930s–1940s. They became widely adopted due to their deep root systems, allowing them to access water efficiently and grow without irrigation. They also offered higher yields than earlier Bourbon types and some level of disease tolerance. Today, they are less widely cultivated due to their susceptibility to diseases such as coffee leaf rust and their need for specific growing conditions. Process: Step 1: Pulping The coffee is pulped in the evening after being harvested during the day and transferred onto cement fermentation tanks, where the fermentation process begins. Step 2: Fermentation The coffee undergoes double fermentation, with an initial 20 hours of dry fermentation followed by an intermediate washing to remove the mucilage. The coffee is then held for a further 24 to 26 hours in fermentation tanks before the final washing and grading in the grading channels. Fermentation time depends on the prevailing temperatures; if temperatures are low (below 17°C), the coffee can be held for longer without any risk of developing ferment flavours. Step 3: Microbial Activity The first hours of fermentation mainly involve the breakdown of mucilage, which takes place through a fungal reaction (yeast) and generally requires cooler temperatures. The second stage of fermentation involves the development of the cup profile and is mainly a bacterial process, occurring at slightly higher temperatures than the fungal stage. Step 4: Monitoring and Control The fermentation process is actively monitored to prevent over- or under-fermentation. They turn the coffee every 12 hours to aerate it and to avoid the buildup of compact layers within the fermentation tanks, which can lead to ferment flavours. Turning also helps ensure uniform fermentation, as beans from the top and bottom of the tanks are mixed. When temperatures in the tanks become too high, they carry out a light washing to reduce the temperature and maintain proper fermentation. Step 5: Washing After fermentation, the beans are thoroughly washed with clean water to remove any remaining mucilage. Step 6: Drying After grading and washing, the coffee is first dried under shade to avoid excess heat during the initial 12 hours after fermentation and to preserve the flavours developed during the process.