Leveraging natural fermentation during post-harvest to create a unique, fruity coffee taste

Nespresso coffee

The exquisite taste of a cup of coffee is the result of much more than perfect roasting and brewing. Many steps along the value chain contribute to highlighting unique flavors and creating ultimately a differentiating and authentic coffee experience.

It all starts with farming high-quality coffees and growing them in their native environment where they can reveal their natural characteristics and flavors. It is also about harnessing post-harvesting practices that lead to a fine modulation of the coffee quality and to expand the range of natural flavors and aromas of the final brew. One example of such post-harvesting practices is fermentation.

Leveraging our long-standing scientific and technical expertise in fermentation, sensory and flavor analysis our scientists gained a deeper understanding of coffee post-harvesting conditions, and their impact on the quality of coffee.

Fermentation is the natural process that takes place at the farm just after coffee cherries are picked. It starts spontaneously thanks to the activity of microorganisms that are naturally present in the environment and on the green coffee beans. Controlling this fermentation is an important post-harvesting practice that is increasingly being adopted in coffee production, although it has been used for many years in other categories of the food industry such as yogurt and cheese for example.

Coffee fruits

"We engaged in a deep scientific investigation into the microbial ecosystem involved in coffee fermentation and the range of flavor molecules in the coffee beans. This enables us to highlight the flavors that are being naturally produced during fermentation and that are maintained in the final cup", says Cyril Moccand, the scientist at Nestlé Research who led the work. "For the first time we were able to reveal a direct link between fermentation and the flavor attributes of a coffee brew. This knowledge can be leveraged to tailor specific fermentation conditions to different coffee varieties, allowing us to highlight new distinct natural flavors and sensorial notes and to consistently maintain their quality, while avoiding raw material loss due to uncontrolled fermentation."

The Nespresso limited edition La Cumplida Refinada coffee, produced in small coffee farms of the Matagalpa region in Nicaragua, is the first coffee to leverage our scientific findings that link fermentation with sensory properties. Through hundreds of fermentation trials, a multidisciplinary team of Nespresso coffee experts, Nestlé researchers and local farmers have been working side-by-side to identify and apply tailored fermentation conditions to the harvested coffee beans.

"The team found that while carefully monitoring the natural process, it was possible to unlock a differentiated sweet and light coffee profile with wild fruity notes", says Frédéric Mestdagh, Coffee Research Manager at Nespresso. "We successfully scaled this post-harvesting process to larger quantities to produce this limited-edition coffee, ensuring the same sensorial quality in each cup."

Mastering this on-farm post-harvest fermentation technique brings smooth notes of candied cherry and pomegranate to the Nespresso La Cumplida Refinada coffee, entirely natural, sustainable and consistent, cup after cup.

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