The use of starter cultures in lab-scale cacao fermentation and its impact on non-volatile compounds and flavor profile

Indonesian cacao exhibits strong potential as Fine Flavor Cacao (FFC), as demonstrated by its recognition at international events. However, maintaining consistent cacao bean quality remains a major challenge, largely due to spontaneous fermentation processes that result in variable microbial communities. This study aimed to optimize laboratory-scale cacao bean fermentation through the application of defined microbial starter cultures. Fermentation was conducted using either a single yeast starter (Pichia kudriavzevii) or a mixed starter culture comprising P. kudriavzevii, Lactiplantibacillus plantarum, and Acetobacter tropicalis. Each treatment utilized 1.2 kg of fresh cacao beans and was performed in duplicate. Following fermentation, the non-volatile compounds composition and flavor profile of the cacao beans were analyzed. The results showed that fermentation with the Pichia starter produced cacao beans characterized by more pronounced floral and woody notes, whereas the mixed starter culture resulted in cacao beans with enhanced fresh fruit notes. Both fermentation strategies yielded cacao beans with high-quality flavor profiles. These findings highlight the potential of starter culture-based fermentation as a viable approach for small-scale cacao processing to achieve consistent and tailored flavor characteristics.