Simulation of UV-C intensity distribution and inactivation of mold spores on strawberries

The practical usage of UV-C to decontaminate fruits has been limited by the difficulty applying a uniform dose to complicated shapes. Simulation of UV-C radiation treatment was investigated in this study to find the optimal treatment conditions. A setup of strawberries being placed on a UV-transmittable film with radiation sources from the top and bottom was proposed. A 4-lamp model with a horizontal distance of 300 mm between the lamps was found to yield the most uniform dose distribution, with mean radiation intensity of 2.00 W m^-2. For this configuration, the treatment time required to achieve one log inactivation of Cladosporium cladosporioides and Penicillium digitatum spores were 3 min 46 s and 1 min 36 s, respectively. Radiation simulation in combination with the inactivation model has been shown to be a useful tool for the optimization of the UV-C inactivation process.