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Aims: Contamination with filamentous fungi reduces the quality of cocoa beans and poses a health risk for consumers due to the potential accumulation of mycotoxins. The aim of this study was to develop antifungal Bacillus cultures for cocoa beans fermentation. Methods and Results: Antifungal activity of 7 Bacillus isolates was investigated using overlay technique. Solid culture media inoculated with bacterial and fungal isolates were cultivated under aerobic conditions at 30 ºC for 5 days. The Bacillus strain with strong antifungal activity was studied and inoculated to 18 kg box fermentations cocoa beans in Cote d'Ivoire in three time-independent replications each including a spontaneous control fermentation. The comparison of inoculated and spontaneous fermentation processes revealed that the Bacillus thuringiensis strain ATCC 10792 don't affected the fermentation process and cocoa bean quality. The anti-fungal in vivo assays revealed that the Bacillus thuringiensis strain ATCC 10792 completely inhibited growth of all fungi on the surface of cocoa beans. The result showed that sensory evaluation of chocolates is not significant differences for all treatment. The sensory evaluation of control and chocolates made from the inoculated cocoa beans with Bacillus showed excellent sensory quality, demonstrating that Bacillus thuringiensis strain ATCC 10792 did not affect aroma, texture and appearance of chocolate. Conclusion: From this study, it is revealed that the addition of Bacillus thuringiensis strain ATCC 10792 during fermentation cocoa beans suppress fungal growth and improve the quality of cocoa beans. Therefore, the anti-fungal culture Bacillus thuringiensis strain ATCC 10792 is recommended for future applications and its capacity to limit fungal growth during industrial-scale cocoa bean fermentation should be investigated in further studies.

Aims: Mold contamination of foods especially by mycotoxin producing fungi is not only a global food quality concern for food manufacturers, but it also constitutes a high risk for human and animal health resulting in massive economic losses globally. This study investigated the effect of Lactic Acid Bacteria (LAB) on the growth of Aspergillus carbonarius strains and their production of ochratoxin A (OTA). Methodology: Seven fresh coffee cherry and 9 dry coffee cherry samples were collected from Man, Daloa and Akoupé 3 main coffee producing regions in Côte d’Ivoire. LAB were isolated from fresh coffee cherries while mold strains were from both fresh and dry coffee cherry. The inhibitory effect against mold growth and the ability for OTA removal of selected LAB strains were tested successively in vitro and then during coffee cherry primary postharvest processing before evaluating their influence on sensory quality of beverage. OTA production ability of molds strains are studied using both solid (CYA) and liquid (CYB) Cazapeck Yeast medium. Results: About 34 fungal isolates belonging to Aspergillus and Penicillium genus were studied for their OTA production using the agar plug technique and HPLC-FD. Five A. carbonarius strains were capable of OTA production between 15.9 and 83mg.kg-1.Out of seven isolates of Lactobacillus plantarum, two were successful in inhibition of mycelial growthproduced fungicidal activity; five were successful in retarding it produced fungistatical activity All of L. plantarum isolates exhibited OTA reduction ability at about 99 %. The inoculation of two highest anti-ochratoxigenic LAB to fermenting coffee cherries resulted in great inhibition of mold growth and OTA contents reduction varying from 63.2 to 82.2%. The addition of LAB to coffee cherries did not influence the sensory attributes of the beverages produced thereof. Conclusion: This study highlighted that LAB are very promising biological candidates for reduction of mold contamination and removal OTA from coffee cherry during primary postharvest processing.