Thailand: Doi Pangkhon, Kenya-style Washed

Sticky, dark toffee up front, balanced by delicate dried apple and sultana, before shifting into a long cocoa aftertaste with a sprinkle of currants.

Doi Pangkhon is a remote village in Chiang Rai, northern Thailand, home to around 300 coffee-producing households. At elevations between 1,100 and 1,450 meters above sea level, the region’s cool climate and rich biodiversity create ideal conditions for growing high-quality coffee. The producers we work with are part of the Merlaeku family -five brothers from the Akha Hilltribe minority - who have been instrumental in developing specialty coffee in the area.

We’ve been working with our sourcing partners, Beanspire Coffee, since 2017. Over the years, they’ve made significant investments in infrastructure, including a wet mill, cupping lab, and improved drying facilities. Their hands-on approach and commitment to quality have helped elevate Thai coffee to new heights. The varieties grown locally include Catuai, Typica, Chiang Mai (a hybrid of SL28 × Caturra × Híbrido de Timor), and SJ133 (genetically identical to Costa Rica 95). 
 
The Kenya-Style Washed Process - Explained 

The Kenya-style washed method (also called double washed or double fermentation) is a multi-stage post-harvest process originally developed in Kenya and now widely used across East African specialty coffee. It is renowned for producing exceptionally clean, crisp cups with vibrant acidity, and is significantly more labour intensive than standard washed processing. 

How the traditional process works: 

After ripe cherries are hand-picked and sorted, they're mechanically de-pulped to remove the outer skin and most of the fruit flesh, leaving the coffee seeds still coated in a sticky layer of mucilage, the sugar-rich fruit residue that clings to the parchment.

In the traditional Kenyan method, the de-pulped beans are placed into fermentation tanks with minimal water for a first fermentation lasting 12 to 24 hours. This is the dry fermentation stage: the beans sit in their own mucilage without being submerged, and naturally occurring yeasts and bacteria begin breaking down the sugars and pectin in the fruit's own juices, without additional water.

The beans are then flushed through water channels, where agitation helps rinse and loosen mucilage. Low-density "floater" beans are separated at this point, one of several quality-sorting steps built into the process.

Next comes the wet fermentation. The beans are immersed in a second fermentation tank for another 12 to 24 hours, restarting fermentation but this time with less sugar and fruit material available. This underwater environment slows and homogenises fermentation, encouraging a cleaner, more uniform breakdown of the remaining mucilage.

Finally, there's a soaking stage. The washed beans are transferred to clean water tanks and soaked for an additional 24 hours. Since the mucilage has been fully removed by this point, enzyme activity within the bean itself increases during the soak. Historically, this final soak also had a practical origin: it allowed mills to hold washed coffee safely while freeing up drying space during busy harvest periods.

After soaking, the beans are spread on raised drying beds a couple of inches deep, initially dried quickly to reduce moisture and lower risk, then mounded deeper and moved to a longer, slower drying track to promote stability. The coffee needs constant turning during this period to achieve even drying, until moisture reaches around 11-12%. 

Why this process matters for flavour: 

Each stage serves a distinct purpose. The initial dry fermentation allows enzymes and microorganisms to break down the mucilage while producing organic acids and other metabolites that contribute to flavour complexity. During fermentation, the bean itself responds to external stress. The lack of oxygen during submersion (hypoxia) and the lack of water during drying (drought stress) both trigger metabolic changes within the seed, altering levels of sugars, amino acids, and organic acids that act as flavour precursors during roasting. The wet soak then adds refinement, producing what many describe as a softer body, more complex acidity, and greater cup clarity. 

What Beanspire changed this harvest: 

For this particular lot from Doi Pangkhon, the producers experimented by extending the dry fermentation stage while significantly reducing the wet fermentation and soaking phases. In previous years they'd followed the more traditional balance between the three stages.

This is a meaningful shift. Research has found that longer fermentation durations enhance the production of flavour precursors, particularly simple carbohydrates like glucose and fructose, amino acids, and organic acids like succinic acid, which drive more pronounced fruity and complex notes during roasting through the Maillard reaction. By keeping the beans in their own mucilage for longer during the dry stage, more of these flavour-developing compounds have time to develop and migrate into the seed. Reducing the subsequent wet and soaking stages then preserves that complexity rather than washing it back towards the cleaner, more neutral profile that a full-length soak would produce.

After fermentation, the coffee was dried on bamboo raised beds for a minimum of 14 days before being transferred to a lowland facility to complete drying more efficiently, an important step given the humidity levels at 1,250-1,450 metres in Chiang Rai during harvest season.

The result, according to Beanspire, is their most expressive and complex harvest in nine years of processing at Doi Pangkhon. A coffee that retains the signature cleanliness and structure of the Kenya-style method, but with greater depth and flavour intensity from the extended initial fermentation. 

• Country: Thailand 
• Region: Doi Pangkhon, Chiang Rai 
• Producers: Merlaeku Brothers x Beanspire 
• Elevation: 1,110 - 1,450 m.a.s.l 
• Varietals: Catuai, Typica, Chiang Mai 
• Processing method: Kenya-style Washed 

Medium to Medium Dark. A steady pace and make sure you don't go too light, as the flavours can easily be muted if so. 

Cupping Notes: Toffee, cocoa, dried apple.

Cup of Excellence Cupping Scores

• Clean Cup: 6/8
• Sweetness: 6.5/8
• Acidity: 6/8
• Mouthfeel: 6.5/8
• Flavour: 6.5/8
• Aftertaste: 6/8
• Balance: 6.5/8
• Overall: 6.5/8
• Correction: +36
• Total: 86.5/100

If you'd like to find out more about how we score coffees, make sure to read our blog post “What Do Coffee Cupping Scores Actually Mean?”