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The effectiveness of the radiation decontamination process was tested for electron beam of energy 200 keV and 300 keV. The energy of electrons was controlled by the measurements of its penetration ability in stack of B3 dosimetric film. In the presented work, the reduction of total aerobic bacteria count was observed, depending on time of irradiation for samples of dried black pepper, onion flakes and bay leaves. The results were compared with the effect observed for the process where high energy electron beam was used. [ABSTRACT FROM AUTHOR]

Abstract: Very extensive production procedure, especially in plants growing under covering, require methods, which would allow quick elimination or substantial reduction of populations of specific pathogens without affecting the growth and development of the cultivated plants. Among soil-borne pathogens, the Phytophthora species are especially dangerous for horticultural plants. In this study, irradiation with electron beam was applied to control Phytophthora cinnamomi. The influence of irradiation dose on the reduction of in vitro growth and the population density of the pathogen in treated peat and its mixture with composted pine bark (1:1), as well as the health of Chamaecyparis lawsoniana and Lavandula angustifolia plants were evaluated. Application of irradiation at a dose of 1.5kGy completely inhibited the in vitro development of P. cinnamomi. This irradiation effect was connected with the disintegration of the hyphae and spores of the species. Irradiation of peat and its mixture with composted pine bark with 10kGy resulted in the inhibition of stem base rot development in Ch. lawsoniana. Symptoms of the disease were not observed when the substrates were treated with 15kGy. In the case of L. angustifolia, stem root rot was not observed on cuttings transplanted to infected peat irradiated at a dose of 10kGy. Irradiation of the horticultural substrates did not affect plant growth. [Copyright &y& Elsevier]

Unsuitable storage conditions or accidents such as floods can present a serious threat for large quantities of book making them prone to attack by harmful microorganisms. The microbiological degradation of archives and book collections can be efficiently inhibited with irradiation processing. Application of EB irradiation to book and archive collections can also be a very effective alternative to the commonly used ethylene oxide treatment, which is toxic to the human and natural environment. In this study was evaluated the influence of EB irradiation used for microbiological decontamination process on paper-based objects. Three different kinds of paper (Whatman CHR 1, office paper and newsprint paper) were treated with 0.4, 1, 2, 5, 10 and 25 kGy electron beam irradiation. Optical and mechanical properties of different sorts of paper treated with e-beam, before and after the radiation process were studied. These results, which correlated with absorbed radiation doses effective for the elimination of Aspergillus niger (A. niger) allowed to determine that EB irradiation with absorbed radiation dose of 5 kGy ensures safe decontamination of different sorts of paper-based objects. [ABSTRACT FROM AUTHOR]

Electrons with energies of 300 keV or lower have the potential to decontaminate the surfaces of various types of food products with minimal loss of quality. The aim of presented work was to determine the effectiveness of the process when applied to naturally contaminated food samples. Black pepper, white pepper and allspice samples were irradiated using electron beam at energy of 300 keV (low energy e-beam) and 10 MeV (high energy e-beam) to confirm the inactivation of bacteria. Total aerobic bacteria were counted before and after the irradiation and bacterial species were determined by a microbial identification system based on MALDI-TOF mass spectrometry. The range of applied low energy electron beam in food products estimated based on the depth-dose profile of electron beam and density of samples was about 300 μm thick. The log reduction in the total number of aerobic bacteria for spices samples irradiated with the high energy e-beam was comparable with that of the low energy e-beam, if estimated doses delivered on the surface were equivalent. (The log reduction by irradiation with 300 keV e-beam for 5 min corresponded to that by ca. 6 kGy irradiation with 10 MeV e-beam in conditions employed in this study). In non-irradiated spices, the dominant species was Bacillus subtilis. In irradiation of black pepper, the dominated species that survived after the irradiation were Cronobacter sakazaki and Bacillus megaterium, regardless of the energy of the electron beam. The effectiveness of microbial decontamination by both the low and the high energy e-beams was comparable for spices, where microorganisms exist in the surface layer. This study suggests the low energy e-beam as an alternative technology for the currently used highly penetrating ionising irradiation to eliminate microbial contamination of spices. • Electron beams of energy 300 keV and 10 MeV were used to eliminate microbial contamination of spices. • The energy of electron 300 keV ensured irradiation only in the external layer of black pepper, white pepper and allspice. • The bacterial species that survived were the same, regardless of the electron energy. [ABSTRACT FROM AUTHOR]