From fermentation to exceptional coffees: the potential of yeast strains

Did you know that coffee cherry fermentation is a crucial process that impacts the aromatic quality of coffee? The use of new yeast strains in coffee cherry fermentation is an exciting and innovative approach that our RD&I teams are passionate about. It promises to revolutionise the world of coffee.

All the major coffee brands are looking for exceptional coffee. One way of doing this is to exploit the potential of the microorganisms, yeasts and bacteria, at the heart of the post-harvest fermentation of coffee cherries. Traditionally, coffee cherry fermentation has been a natural process, shaped by microorganisms in the environment.  However, the introduction of specific yeast strains opens up a whole new world of possibilities for creating unique and extraordinary coffee flavours. 

Researchers from Lesaffre and its Fermentis by Lesaffre business unit worked in partnership with the Nicafrance Foundation, which runs innovative projects in its laboratories located in the heart of the coffee-growing region of Nicaragua.

“From the Group’s collection, we selected 12 particularly robust yeast strains, which demonstrated in laboratory growth tests their ability to withstand the stressful conditions of fermentation, such as high temperatures, high concentrations of caffeic acid and low pH levels.” explains Evelyne Fonchy-Penot, Technical Manager at Fermentis.

The Q-grader’s no-holds-barred review 

Following fermentation trials under real conditions on the farm in Nicaragua, the 12 batches of fermented green Arabica coffee were sent for tasting tests to Q-grader (sensory experts) from a major coffee brand and the Foundation. 

Sensory analysis of the different products, carried out in accordance with the SCAA protocol(1) , revealed a very wide range of aromatic profiles in the coffees tasted. All the yeasts selected contributed a variety of fruity, floral, sweet or cereal notes, creating an attractive aroma and taste. These preliminary tests represent the first steps towards unique and delicious flavour profiles. 

Developments in fermentation techniques, combined with advances in our understanding of microbial activity, mean that coffee growers can now offer new experiences for coffee lovers. 

On the strength of these results, Fermentis by Lesaffre shared the fruit of its research at the latest Congress on Coffee Science organized in Vietnam by the International Association for Coffee Science and Information (ASIC). 

1 Specialty Coffee Association of America

 Réalisation des essais de fermentation en conditions réelles au sein de la ferme au Nicaragua