Belgian researchers from University of Leuven and the Flanders Institute for Biotechnology have found that the yeasts used to ferment cocoa during chocolate manufacture can help alter the aroma of the end chocolate product.
The research is published in Applied and Environmental Microbiology, a publication of the American Society for Microbiology.
For the research, the study authors sourced for robust yeast strains which were capable of outdoing the invading yeast strains that inundate the cocoa beans during fermentation process, reported American Society for Microbiology.
Esther Meersman, a post-doctoral researcher with Steensels at the two institutions, was quoted in the publication saying that after harvesting the cocoa beans are gathered in large plastic boxes, or piled up in large heaps, in the farms where they are grown.
She stated that the coffee beans are covered by a gooey pulp, which is fermented by yeasts and bacteria.
Esther Meersman said that any element from the environment could enter the mix and influence the final flavor. However, by outnumbering other microbes, robust yeast strains could contain such unpredictable variability in taste, she said.
However, the scientists noted a marked difference in the aroma of chocolates made from fermentations using different robust yeasts. The differences surprised them as there was a distinction of only the yeast strains.
Each time, identical recipes were used and the fermentation process was same, hence the results were enlightening, the scientists said. Then the team began to breed unique yeast hybrids which would combine robustness and aroma production.
"We were initially surprised that the volatile flavor compounds are retained in the beans during drying and roasting." The researchers theorized that the volatiles were protected from the evaporation as they are dissolved in the fat fraction."
The research was conducted in collaboration with confectionery giant Barry Callebaut. The researchers combined two important characteristics of yeast in single hybrid variants - the capability to dominate the cocoa fermentation, and the ability to deliver a specific flavour.
Steensels was quoted by American Society for Microbiology as saying:"This means that for the first time, chocolate makers have a broad portfolio of different yeast strains that are all producing different flavours."
Steensels said: "This means that for the first time, chocolate makers have a broad portfolio of different yeast strains that are all producing different flavors. This is similar to the current situation in beer brewing and wine making. A new era of chocolate may be dawning."
