LIMITED EDITION: FRANCO HUACHES, SL9 (Inca Gesha)

Franco Huaches Montalvan cultivates coffee at his farm Finca La Lúcuma in El Limón, Cajamarca. Franco has a keen focus on agricultural practices and plant health which he has refined over the years. He uses the broadcast method to distribute fertiliser across the field rather than targeting individual plants, and practices meticulous pruning to encourage new growth and keep the plants healthy and productive.

During a difficult period when plantations were affected by rust and prices for conventional coffees were very low, Franco sought technical support from an agricultural engineer, who recommended introducing the Gesha variety. This decision proved incredibly successful, leading to significant results in regional and national competitions and improving both the quality and value of the coffee.

The Gesha turned out to be SL9, known colloquially as “Inca Gesha”, and is not in fact genetically related to Gesha. Recent DNA testing reveals that SL9 is an Ethiopian legacy variety, genetically similar to selections from Scott Agricultural Laboratories in Kenya. Both varieties are celebrated for their highly floral, tropical cup profiles, despite their different lineages.

Harvesting is carried out selectivity, only cherries at their precise peak of ripeness are hand-picked, a standard that is instilled in every worker through thorough training before the season begins. To maintain this level of quality, each picker is limited to no more than three cans per day, a deliberate measure that prevents any green or overripe fruit from compromising the lot.

The harvested cherries are then pulped and transferred to sealed fermentation tanks, where the seeds rest undisturbed for 36 hours without the addition of water. This controlled, anaerobic environment allows natural sugars to develop and complexity to emerge organically. Once fermentation is complete, the seeds undergo a meticulous washing process to remove all remaining mucilage, leaving them clean and primed for drying.

Drying takes place in a parabolic dryer, where the clean parchment coffee is spread in carefully uniform layers and turned at regular intervals to ensure consistent, even dehydration. The process continues until the seeds reach a final moisture content of 11–12%, the precise threshold at which quality and stability are preserved in equal measure.

The dried coffee is then rested for a few weeks in bags on wooden pallets, a practice that allows airflow, reduces the risk of off-flavours being developed from contact with the ground and allows the moisture to stabilise and homogenise. At every stage, precision and patience are applied in equal measure, because the quality in the cup begins long before it is roasted.

SL9 is a coffee variety surrounded by uncertainty. Although the name comes from a historic selection program in Kenya, genetic analysis suggests it is more closely related to Ethiopian coffee lineages and is now grown primarily in Peru. First catalogued as an early selection by Kenyan researchers, SL9 fell out of favour due to low productivity and susceptibility to disease, leading many to assume it had disappeared. However, modern DNA testing of a Peruvian variety commonly known as Inca Gesha has shown it is not true Gesha, but instead is very closely related to SL9.

How this variety arrived in Peru remains unclear. Researchers and coffee historians have proposed several possibilities, including introductions through agricultural seed collections, connections to other historic varieties, or independent movement of related plant material from East Africa. The historical record is incomplete, and the loss of important agricultural documents in Peru has made verification difficult. Recent genetic findings add further intrigue, suggesting that coffee matching the SL9 profile may still exist in Kenya, despite long-held assumptions that it had vanished from cultivation.

What is beyond dispute is the quality of the coffee. SL9 is prized for its highly aromatic, expressive cup profile, often compared to Gesha for its floral character and elegant structure. Typical flavour notes include jasmine, citrus blossom, tropical fruit and stone fruit, supported by bright acidity and a clean, tea-like finish. Today, the variety is gaining recognition among specialty producers in Peru, particularly in high-altitude regions, where it is increasingly seen as distinctive and sought-after, with exceptional flavour and a fascinating, unresolved history.

The washed process was designed to minimise the risk of off-flavours caused by uncontrolled fermentation during the natural process. Cherries are typically sorted using a flotation tank, where under-ripe or defective fruits float to the top and can be removed. The remaining cherries are then pulped and left in a tank to ferment until the sticky fruit mucilage is soft enough to be washed off the parchment, a paper-like layer surrounding the seed.

The design and cleanliness of the tanks used for fermentation are crucial, and the type, degree and speed of microbial activity depends on various factors. These include the amount of fruit remaining, the presence of bacteria and yeasts, whether the tank is filled with water, and the environmental conditions.

Once the mucilage has sufficiently degraded, it's washed away with water. The remaining parchment coffee, as it's commonly called, is then dried until it reaches a safe moisture content. The bacteria rich and sugary water used in the process must be treated carefully, as it can cause algae blooms if it enters streams and rivers.

In situations where large amounts of coffee are processed in bulk, such as in Ethiopia, some operations have found it economical to use a mechanical de-mucilager. This device removes all the fruit from the parchment with minimal water, bypassing the fermentation stage entirely. However, some believe this leads to a reduction in cup quality, as many flavour precursors are created through fermentation.