Effect of chemical and environmental factors on Aspergillus ochraceus growth and toxigenesis in green coffee Original Research Article

Post-harvest processing (traditional or ecological wet method, and dry method) and coffee pH did not play a significant role in Aspergillus ochraceus growth and OTA production. However, Aw did play a key role: the optimum for growth and toxigenesis was 0.95; below 0.80, coffee was protected. Temperature affected the rate of toxin production, when Aw was compatible: toxigenesis occurred from 10°C with an optimum at 35°C. The critical stage in the process was drying, where conditions propitious to A. ochraceus (Aw of 0.99–0.80) could be found for 2 days or more. Caffeine and chlorogenic acids had an inhibiting effect on OTA production.