As the specialty coffee scene continues to grow, fermentation and experimental processes are becoming more popular. Opinions on natural coffees show they can be divisive for the public, as the flavours found in the cup can be quite unique. Some consumers enjoy the wine-like flavours, while others view the ‘fermented’ flavours as a negative attribute.
However, the increase in fermenting coffee with purpose is showcasing coffees with some irresistible flavour notes. For roasters, fermented coffees can be a unique and novel offering for consumers, often for a higher price.
To learn more about the experimental fermentation processes sweeping the specialty coffee industry, I spoke with Beth Williams, who is the head of the UK and European branches of Cofinet, a family-owned business that has grown and distributed Colombian coffee for over 80 years.
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Cofinet was started in 2015 by fourth-generation coffee producers, Carlos and Felipe Arcila. The pair had been working as civil engineers in Sydney when they noticed the growing specialty coffee culture in the country. Over time, Cofinet has become a leader in experimental coffees, which have featured in competitions and created a buzz at tastings in coffee festivals around the world.
“We began experimenting with the idea being, if we can process lower quality but reliable varietals to improve the flavour profile, we would be able to sell those varietals for more,” explains Beth, who also served as the Head of Coffee for Colonna Coffee. “Then, we teach these key processing techniques, that are inexpensive for producers, all over Colombia to improve quality.”
The aim of Cofinet was to return value to Colombia and it’s coffee producers. Today, the business works with over 200 producers across the country. “The business has expanded dramatically,” Beth says. “But this is also due to a unique Colombian trait: they are always willing to try new things and take risks for the chance to be the best. This is why we’re seeing so many extraordinary techniques coming out of the country.”
Colombia is the third-largest coffee-producing country in the world by volume. It is also home to plenty of different growing regions with their own microclimates. These varied conditions mean that Colombian coffee can vary significantly in flavour. More so, processing is a necessary step in the coffee supply chain and it has a marked effect on the flavour of a coffee in the final cup. However, in recent years, experiments with processing have become more widespread.

Understanding experimental processing
Experimental processing is a term used to describe any particularly new or innovative processing method in the specialty coffee sector. Many of these leverage extended fermentation times. Fermentation in coffee production technically begins as soon as the cherry is picked.
In essence, fermentation is a metabolic process that turns sugars into acids, gases, or alcohol. It is also often used broadly to describe the growth of microorganisms. In his book, ‘The Coffee Dictionary’, Maxwell Colonna-Dashwood states that “changes in temperature, time, sugar, and the type of bacteria will create different results.” Fermentation has a marked impact on coffee flavour, but it must be controlled. Otherwise, the flavour can become overpowering or unsuitable, or the coffee could potentially become harmful.
Experimental fermentation can create plenty of unusual flavours in the cup. At Cofinet, experimentally processed coffees have a variety of outstanding flavour notes, including hints of lavender, purple grapes, and papaya to After-Eight mint chocolate.
Cofinet also offers a range of fruit-fermented coffees, including banana, lychee, orange, peach, strawberry, and passion fruit. For these processes, the coffee is exposed to a dry anaerobic fermentation period of 72 hours with the pulp on. Fruit pulp and wine yeast are added during this stage. Then, the coffee cherries are pulped and placed to dry on raised beds with the desired fruit pulp placed amongst the coffee until the ideal moisture content is achieved.
These coffees can be an interesting addition to any roaster’s menu, particularly for consumers looking to try something different. Additionally, roasters can sell them at higher price points due to their unique profiles, and package them in small quantity packages for a more luxurious experience.

Can experimental processing increase a coffee’s quality?
“These fermentation processes allow us to change the flavour profile of a coffee,” Beth explains. “For instance, a washed Castillo might score 83 points, but if we combine its complexity with an extended fermentation, we could raise this to 86 points or more. This means we can pay the producer for a higher-scoring coffee, so it is much better for them.”
To make offerings more accessible, Cofinet tries to ensure the different methods do not add excessive costs for the producers. In order to do this, Beth explains they always teach fermentation using GrainPro bags, for example, or encourage producers to use fruit that grows on their land.
Cofinet has received glowing feedback about its coffees, which has allowed the business to facilitate discussions between producers and roasters about what is happening at origin. “Transparency is key. Whatever we and the producers are doing, we make sure it is documented all the way through to the roaster. It is of paramount importance. If we add fruit to the fermentation, we will say so.”
She adds fruit fermented coffees have been extremely popular, as they make excellent talking points. “They’re also great because the flavour profile is obvious – it is fermented with strawberry, and therefore, it tastes like strawberry. So, it’s great for customer communication and experience.”
“We do so many processing methods. For example, we have some methods that increase the presence of lactic bacteria or washed carbonic maceration lots that are incredibly juicy. It really is an exciting time and I love seeing what each season will bring, whether a new processing method or hybrid varietal.” If you choose to invest in such high-quality coffee, be sure to invest in the packaging to match. MTPak Coffee can help to make it a coffee to remember, with bespoke and luxurious packaging in bags or boxes as small as 50g to 100g. Our sustainable coffee bags are made using kraft paper, rice paper, or multilayer LDPE packaging with an environmentally friendly PLA lining, while our coffee boxes are made with recycled cardboard. Our eco-friendly customisation techniques include spot UV with a glossy, satin, or matte finish, embossing and debossing, as well as hot foil stamping in a variety of colours.