Antimicrobial effects of ionizing radiation on artificially and naturally contaminated cacao beans.

With an initial microbial level of ca. 10 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 degrees C, respectively. Bahia cacao beans were artificially contaminated with dried spores of Aspergillus flavus and Penicillium citrinum, giving initial fungal levels of 1.9 x 10 and 1.4 x 10 spores per g of whole Bahia cacao beans, respectively. The average D(10) values for A. flavus and P. citrinum spores on Bahia cacao beans were 0.66 and 0.88 kGy, respectively.