Processing of food and agricultural commodities with electron beam from microtron

A microtron machine source installed by the Centre for Advanced Technology (CAT), Indore, at Mangalore University, was used in the study. The machine was operated at a beam power of 1.8 W, beam energy of 8.6 MeV, and a beam current of 20 mA. After initial standardization, the irradiation of commodities was carried out. The doses employed were 0.06 kGy for onion, 0.10 kGy for potato, 0.25 kGy for rawa, and 8 kGy for spices. The desired dose was delivered by exposing the samples from the two opposite sides of the box. The microbial load in spice samples was determined immediately after the experiment, as well as after six months of storage at the ambient temperature (26±2 degC). Onion and potato samples were stored for a six months period both at ambient temperature and 15 degC for observing the effect of electron beam irradiation on sprouting in these commodities. Rawa samples were stored at ambient temperature for observing the effect of electron beam irradiation on insect disinfestation. The electron beam irradiation at the recommended doses was found to be as effective as gamma radiation in bringing down the microbial load of the tested spices to the desired level, disinfestations of rawa, and inhibition of sprouting in onion. In the case of potato even four-side irradiation of the product box did not inhibit the sprouting completely. This indicated the necessity of standardization of machine parameters for uniform dose distribution in the product box for each commodity. These lab-scale studies showed that electron beam could in principle be used for processing of various food products after standardizing the machine parameters and ensuring uniform dose distribution in the product. Use of this technology on commercial scale would need standardization on larger machines