Antimicrobial Effects of Ionizing Radiation on Artificially and Naturally Contaminated Cacao Beans

With an initial microbial level of ca. 10⁷ microorganisms per g of Ivory Coast cacao beans, 5 kGy of gamma radiation under an atmosphere of air reduced the microflora per g by 2.49 and 3.03 logs at temperatures of 35 and 50°C, respectively. Bahia cacao beans were artificially contaminated with dried spores of Aspergillus flavus and Penicillium citrinum, giving initial fungal levels of 1.9 × 10⁴ and 1.4 × 10³ spores per g of whole Bahia cacao beans, respectively. The average D₁₀ values for A. flavus and P. citrinum spores on Bahia cacao beans were 0.66 and 0.88 kGy, respectively.