Research investigates how fermentation conditions can alter chocolate flavour

The flavour of chocolate develops during the processing of cocoa beans, and new research shows how changes made at this step can produce new flavours.

The research, undertaken by an international team of researchers from Denmark, Nicaragua, and Belgium, investigated how different fermentation conditions can affect the activity of the microorganisms naturally present on the cocoa beans, and how this alters the flavour of the beans after they are fermented.

Fermentation is one of the steps where the flavour develops, as well as roasting, and it is considered important to the final quality of chocolate. “We have also learned how to fine-tune the cocoa by fine-tuning the process itself, which means that you can get a higher quality out of your raw materials if you understand these processes,” said Dennis Sandris Nielsen, a Professor in the Department of Food Science at the University of Copenhagen.

For the study, the team analysed fermentations of cocoa beans from different parts of Nicaragua, and fermentations under different oxygen levels using a combination of high throughput sequencing, chromatography and sensory analysis. This gave the researchers an understanding of the quality of the cocoa in relation to the processing, explained Nielsen.

“Overall, our findings show that the treatment the cocoa receives after the harvest is at least as important for the quality and flavour as the genetics of the cocoa. Where the cocoa was grown also has some significance. By varying the conditions during fermentation, we can therefore also reasonably predict the final taste, which provides good opportunities for high-end producers in particular to develop chocolate with different flavours and scents.”