Laboratory Microbes Put Chocolate Flavors under Scientists’ Control

The unique flavors of high -end chocolate flavors – which may include citrus notes, wine wafts and subtle spice notes – have often been attributed at the origin of cocoa. The farmers of the tropical equatorial regions of the “cocoa belt” have exploited harvesting techniques of several centuries to coax cocoa beans which offer the best taste – with the surprising help of tiny natural fermentators: microbes.

Now, researchers have discovered that the fundamental fermentation of chocolate production can be reproduced with laboratory controlled microbial communities to successfully recreate the complex flavors of beloved pieces.

“We were able to change the flavors to look like different regions simply by changing the microbes,” explains David Gopaulchan, international researcher at the University of Nottingham in England and the main author of the new study describing the results in Nature microbiology. “It’s like hacking an old process because we are closing cocoa beans since we have chocolate. It’s hundreds of years ago. ”

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What’s going on to the taste of chocolate?

Farmers cultivate cocoa and harvest the pods, which are open to recover the seeds and the white creamy pulp. This is left on “healing” for several days in wooden boxes, baskets, polystyrene coolers or large heaps on the leaves on the ground, creating the perfect environment for microorganisms to ferment the beans.

“If you jump this process, your beans do not taste much; He has more taste of plants. Fermentation is therefore super important in the development of flavor precursors, ”explains Gopaulchan. Other fermented foods such as wine, cheese and beer are often intentionally innovated by the manufacturer, generally with the same stumps of microorganisms. For chocolate fermentation, “it’s completely spontaneous and uncontrolled. These are the microbes that exist on the farm, ”he says.

This contributes to the enormous variety of fine chocolate flavors – and millions of farmers through the cocoa belt with each bean closed with variable microbial communities, he says. The majority of cocoa beans produced on a global scale go in bulk chocolate – which generally has a taste of soft chocolate and soft -amer. But a smaller percentage enters into fine flavor Chocolate, which has a basic chocolate flavor, with a complex range of other notes.

For example, “my country of origin, Trinidad, is known for chocolates that have a taste for wine, but other regions like Venezuela are known to have very nut profiles in their beans”, explains Gopaulchan.

Several other factors throughout the growth, harvesting and manufacturing process can influence taste, including soil, climate and beans. “Plant genetics certainly play a huge role, but you can make a bad chocolate from good genetics with bad fermentation,” said Caitlin Clark, senior food scientist in Colorado State University Food Innovation Center, which was not involved in the new research.

GOPAULCHAN had previously studied the role of diversity in cocoa genes internationally Cocoa Genebank of the University of Antilles, St. Augustine’s Cocoa Research Center. In addition to agricultural locations, “it is the longtime belief that the flavor of chocolate depends largely on the genetics of the plant,” he said. “But what we show is that these microbes and this fermentation process have a huge impact. I would even say that it is probably the biggest impact on the final flavor profile.”

Check the fermentation, control the flavor

In the new study, Gopaulchan and his colleagues collaborated with three cocoa farms in separate environments in Colombia: the mountainous region of Santander, the dry valley of Huila and the Pacific of Antioquia. Using beans naturally fermented on site, the team used DNA sequencing and metabolic modeling to identify the network of interactions between various bacteria and yeasts that conduct fermentation.

Among the many microbes that have been genetically identified, the team has identified a central group which could reproduce metabolic signatures – such as volatile sensory organic compounds – a good chocolate flavor. The researchers have isolated and tested these strains on beans uncharted in sterile wooden boxes under controlled conditions. Their analysis revealed that, chemically, the beans fermented in the laboratory corresponded to the flavor profiles of the Premium cocoa. But how the beans taste?

The researchers had a sensory panel formed at the Cocao Research Center Taste Caco “Liquors” – the semied pasta of roasted beans on the ground – of the three farms and the laboratory without knowing who was. They marked laboratory liqueurs – as well as those of the farms of Santander and Huila – as having similar attributes to the fine flavors of the reference beans of Madagascar, while the antioquia liqueur was more similar to the cocoa in bulk.

“We have found a lot of fruity, slightly spicy and floral flavors from this community of microbes,” explains Gopaulchan.

The results support what farmers and the chocolate industry have seen in practice, says Clark. “The fermentation of cocoa is notoriously difficult to study because it is so variable and you cannot really reproduce it in a laboratory, so I thought they had done a good job to know which factors isolate and highlight,” she said.

GOPAULCHAN hopes that the design of concept proof could possibly lead to microbial “beginners” to give farmers more control over the fermentation process and the resulting flavors. Farmers, in particular small scales, could be able to preserve the quality of their cocoa beans, known as Gopaulchan, especially when fermentations fail from an unexpected rain season or unwanted microbes.

Clark, however, sees such a platform give mainly a step to large traditional chocolate suppliers who try to control the consistency closely, a lot after a lot. “The variation in chocolate flavor is a real negative if you try to make each hershey chocolate bar around the world, has the same taste every time,” says Clark. “Research like this benefit people who try to give chocolate the taste much more than what benefits people who try to make the taste of chocolate interesting and different.”

Some companies have expressed interest in using this type of technology to create a chocolate flavor without any cocoa beans, says Gopaulchan. But that could be “disruptive for industry,” he adds.

In the end, he hopes that research could also help chocolate manufacturers with fine flavor – even by helping them to design entirely new flavors. “We have identified microbes that make cocoa beans more like cheese or wine. Others, you can get a strong meat flavor, ”explains Gopaulchan. “It is wild that you can get a range of completely different flavors by simply changing the microbed combinations. Now, we don’t want to eat cheese chocolates, but I think that for other types of food, there are possibilities.”