On-farm Controlled Cocoa Fermentation with Lyophilized Candida tropicalis Improves Efficiency and Sensory Attributes

The fermentation of cocoa beans is one of the most critical steps in processing the beans and producing high-quality chocolate and related products. To control this step and ensure the quality of the cocoa beans, the main microorganisms responsible for this process have been isolated, characterized, and used in cocoa bean processing. The objective of this study was to evaluate the effect of using the yeast Candida tropicalis , either in monoculture or in coculture with Saccharomyces cerevisiae , on the controlled fermentation of cocoa beans at the pilot scale, in order to improve the sensory, physicochemical, and nutritional quality of the beans and their derivative products. To this end, the harvested cocoa pods were shelled, and the beans were collected, homogenized, and divided into three 50-kg batches, including one control and two experimental batches. The control batch was not inoculated; as for the other two batches, one received primarily freeze-dried Candida tropicalis at a concentration of 10 5 cells/g of beans, and the other received a mixture of Candida tropicalis and Saccharomyces cerevisiae at a concentration of 10 5 cells/g of beans. Fermentation was carried out for 144 hours (6 days); samples were taken every 12 hours for analyses of fermentation index, cut test and temperature. After fermentation of the cocoa beans, the 72-hour and 144-hour beans were characterized biochemically and organoleptically. The freeze-dried microbial starters of Candida tropicalis promoted a more rapid increase in temperature, fermentation index, and the proportion of well-fermented brown beans compared to the trial combining the two strains and the control. Furthermore, biochemical analyses indicate that the fermentation trial using Candida tropicalis alone for 72 hours showed the highest levels of bioactive compounds and a low concentration of antinutritional compounds. Organoleptic analyses, meanwhile, reveal a more pronounced preference for the sample fermented with Candida tropicalis alone for 72 hours. In summary, freeze-dried microbial starters of Candida tropicalis alone reduces fermentation time from 144 hours to 72 hours—a reduction of 3 days—while preserving the bioactive properties.