Influence of specific Saccharomyces cerevisiae yeats on cocoa beans flavor and final chocolate quality

Chocolate is a “pleasure” food whose organoleptic quality is essential to the product's value. The aromatic quality of chocolate comes from many parameters, some are intrinsic to the raw material, and others are driven by the manufacturing process. In the frame of a research project dealing with the management of cocoa fermentation process, we investigated the impact of specific yeasts inoculation on the quality of cocoa beans after fermentation and on the final sensory quality of the chocolate Two different yeasts have been inoculated and fermentations were compared to a spontaneous fermentation (standard cocoa). Then, the beans were transformed into chocolate via a standard process and the sensory characterization of these samples was carried out. The analysis of the volatile fraction and the biochemical composition have also been done on beans and chocolate. The results of the beans fermented by selected yeasts show levels of sugars (sucrose, glucose and fructose) lower than in standard cocoa. The polyphenol contents are also impacted by depending on the fermentation process. The analysis of the volatile compounds were also performed on all fermented beans, and important differences were detected. Among the various chemical families measured, the alcohols and esters are more abundantly present in the fermentations carried out with the yeast starters. The sensory tests also confirm that the quality of these beans are also considered better. In conclusion, these studies confirmed the high interest to better control the fermentation step with specific yeast inoculation, in order to improve the final quality of chocolate.