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Editorial sacred-geometry artwork for SL17; not a documentary photograph
Variety

SL17

Quick definition

SL17 is a coffee variety selected by Scott Agricultural Laboratories in Kenya. It is a high-quality selection known for its distinct flavor profile and adaptation to the Kenyan coffee-growing regions.

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What is SL17? It is a specific coffee variety selected by the Scott Agricultural Laboratories (SL) in Kenya during the 1930s. The SL series is widely considered one of the most important contributions to coffee quality in East Africa. Researchers at the time were tasked with identifying trees that could produce exceptional coffee while also being well-adapted to the specific environmental conditions of the Kenyan highlands.

Coffee SL17 was selected through a process of individual tree evaluation. The researchers looked for trees that exhibited high cup quality, good yield, and resilience. While SL28 and SL34 eventually became the most famous and widely planted selections from the SL series, SL17 remains a significant part of the genetic diversity found in Kenyan coffee plantations. It is a testament to the thoroughness of the original research program.

In the cup, SL17 is known for its complexity and bright, lively acidity. Like other SL varieties, it is often associated with the classic Kenyan flavor profile, which includes notes of blackcurrant, citrus, and a wine-like body. Because it is a distinct selection, it may offer a slightly different balance of flavors compared to its more famous counterparts, making it a favorite among roasters who enjoy exploring the nuances of Kenyan coffee.

For the coffee professional, SL17 is a piece of living history. It represents the era when coffee research was focused on identifying the best-performing trees within existing populations. By selecting for quality and adaptation, the researchers at Scott Agricultural Laboratories helped to establish Kenya's reputation as a producer of some of the world's finest coffees. Understanding these varieties is key to appreciating the depth and complexity of the Kenyan coffee supply chain.

In practice, SL17 is a high-quality variety that thrives in the high-altitude, volcanic soils of Kenya. It is typically processed using the traditional Kenyan washed method, which further enhances its bright acidity and clean cup profile. For the consumer, it provides a sophisticated and vibrant coffee experience that showcases the unique terroir of the region.