The lactic dry hull process is a specialized and experimental method of coffee
processing that aims to develop unique flavor profiles by leveraging lactic acid
fermentation and minimal water usage. This method combines elements of
natural (dry) processing with specific fermentation techniques to enhance the
coffee's complexity and depth. Here’s a detailed explanation of the lactic dry
hull process:
1. Harvesting
Coffee cherries are selectively handpicked when they are fully ripe to ensure
the highest quality beans.
2. Lactic Fermentation
The harvested coffee cherries are placed in fermentation tanks or containers
designed to promote lactic acid fermentation. This is typically done in an
oxygen-limited environment to encourage the growth of lactic acid bacteria.
Fermentation Duration : The cherries are left to ferment for a specific
period, which can range from several hours to a few days, depending
on the desired flavor profile.
Monitoring : Temperature, humidity, and pH levels are closely
monitored to ensure the proper development of lactic acid bacteria
and to control the fermentation process.
3. Drying
After the fermentation period, the cherries are spread out to dry. This is similar
to the natural (dry) process, where the entire cherry is dried with the bean
inside.
Drying Beds : The cherries are spread out on raised beds, patios, or
drying tables to dry in the sun.
Turning : The cherries are regularly turned to ensure even drying and to prevent mold or over-fermentation.
Duration : Drying can take several days to weeks, depending on
weather conditions and the specific practices of the producer.
4. Drying Hulling
Once the cherries are fully dried, they undergo dry hulling. This process
involves mechanically removing the dried outer layers (the cherry skin and
parchment) to reveal the green coffee beans inside.
5. Sorting and Grading
After hulling, the beans are sorted and graded based on size, weight, and
quality. This step ensures that only the best beans are selected for export and
roasting.
Flavor Profile
Lactic dry hull process coffee is known for its distinctive and often complex
flavor profile, characterized by:
Enhanced Acidity : The lactic acid fermentation process can enhance
the coffee’s acidity, making it bright and vibrant with a creamy
mouthfeel.
Complexity : The process creates a complex and layered flavor profile,
with fruity, floral, and sometimes dairy-like notes (such as yogurt or
buttermilk).
Sweetness: The natural sugars in the cherries contribute to a
pronounced sweetness in the final cup.
Body : The coffee typically has a fuller body and a syrupy mouthfeel.
Benefits
Distinctive Flavors : The lactic fermentation process produces unique
and highly sought-after flavors, appealing to specialty coffee
enthusiasts.
Minimal Water Usage : The process uses minimal water, making it
more environmentally sustainable compared to washed processes.
Controlled Fermentation : The fermentation process allows for
precise control over flavor development, leading to more consistent
results.
Challenges
Complexity : The method requires careful monitoring and precise
control of fermentation and drying conditions.
Labor and Expertise : It is labor-intensive and requires a high level of
expertise to execute properly.
Risk of Defects : There is a higher risk of off-flavors or defects if the
process is not carefully managed.
