Application of ozone in peanut kernels: A multiscale model approach and effects on filamentous fungi decontamination

Toxigenic fungi in peanuts cause serious damage to human and animal health; therefore, studying the forms of decontamination is imperative, and for this purpose, ozone is highlighted. This work addressed fungal decontamination and its relationship with the ozone concentration profile in a silo and the peanut grain itself. The main fungal genera found in peanuts (Penicillium, Aspergillus and Fusarium) showed significant growth reduction (P < 0.0001) after ozone treatment. The average value of aflatoxin B1 production by Aspergillus sp. Isolated from peanut kernels was 7.4 μg mL−1. The reduction in Aspergillus sp. Growth reached 87% within 240 min of the ozone treatment. Numerical simulation and experimental validation showed that ozone exhibits a strong concentration gradient in the silo and penetrates the grain up to ∼20% of peanut thickness. This study shows that there is a minimum ozone dosage to eliminate fungi and not cause lipid peroxidation on the peanut surface.