Evaluation of ultraviolet irradiation effects on Aspergillus flavus and Aflatoxin B1 in maize and peanut using innovative vibrating decontamination equipment

Abstract

This study investigated the effectiveness of the ultraviolet irradiation of the C region (UV–C) for the decontamination of Aspergillus flavus and aflatoxin B1 (AFB1) on artificially inoculated maize and peanut using innovative decontamination equipment that supports vibrations to achieve semi-fluidization of the grain/kernel material and getting equal irradiation of all surfaces of irradiated foods. UV irradiation is a non-thermal alternative to thermal processes commonly used in food processing with a well-known effect on AFB1 degradation. Samples of maize and peanut were exposed to UV-C irradiation with a total dose in the range of 1080–8370 mJ/cm2. Analysis by Tracker and ImageJ software confirmed the even distribution of irradiation on all surfaces during the entire duration of exposure. The highest reduction of A. flavus count was observed after ten days of incubation and irradiation treatment delivering a dose of 8370 mJ/cm2 achieving A. flavus count reduction of 4.4 log CFU/g in maize and 3.1 log CFU/g in peanut. Depending on the treatment, AFB1 reduction level in maize ranged from 17 to 43% and in peanut ranged from 14 to 51%. Sensory and physical testing of the peanut samples showed only minimal changes in the evaluated characteristics caused by different levels of the UV-C treatment. Presented results demonstrate a potential for the use of the presented approach as an effective reduction strategy for both A. flavus and AFB1 in maize and peanut.