By the time chocolate makes it to your mouth, you probably aren’t thinking about the fact that it’s actually a fermented product. But long before it’s made into bars, the raw cocoa beans undergo fermentation, and scientists are now beginning to discover that this underappreciated yeasty step might be more important than you think.
Back in July, a team of researchers from The University of Leuven and the Flanders Institute for Biotechnology published a paper suggesting that selecting specific yeasts for use in the fermentation of cocoa beans could not only result in better quality chocolate than those created through the traditional processes of natural fermentation, but might also make it possible to use different yeasts “to create a whole range of specialty chocolates to match everyone’s favorite flavor.”
Now, a mere four months later, that same team has started turning those promises of unique new chocolates a reality. In another very sweet paper with a very dry title – “Tuning chocolate flavor through development of thermotolerant Saccharomyces cerevisiae starter cultures with increased acetate ester production” – these devoted chocolate scientists have shown that, indeed, different yeasts can alter the aroma and flavor of chocolate by creating different esters which change the final scent of the product. “We were initially surprised that the volatile flavor compounds are retained in the beans during drying and roasting,” Esther Meersman, one of the paper’s authors, said in a statement. But the team proved that identical coca beans fermented with different yeasts did yield chocolates with different properties.
“This means that for the first time, chocolate makers have a broad portfolio of different yeast strains that are all producing different flavors,” said postdoctoral researcher Jan Steensels. “This is similar to the current situation in beer brewing and wine making.”
That being said, it seems more research is necessary to figure out just how to harness all these potential flavors and aromas. The team focused much of their work on fruity esters, but found other changes as well. “In addition to the variation in fruitiness levels, several other remarkable differences between chocolates produced using different starter cultures were detected,” the authors wrote in their final discussion. “For example, several chocolates differed significantly in cocoa, bitter, sour and floral notes.”
Now if they can find a way to alter the note that makes me feel guilty about eating it.