Skip to main content
ARS Home » Pacific West Area » Hilo, Hawaii » Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center » Tropical Crop and Commodity Protection Research » Research » Publications at this Location » Publication #374340
Research Project: Pre-and Postharvest Treatment of Tropical Commodities to Improve Quality and Increase Trade Through Quarantine Security

Location: Tropical Crop and Commodity Protection Research

Title: Microbicidal effectiveness of irradiation from Gamma and X-ray sources at different dose rates against the foodborne illness pathogens Escherichia coli, Salmonella Typhimurium and Listeria monocytogenes

Author
item BEGUM, T - Institut National De La Recherche Scientifique (INRS)
item Follett, Peter
item HOSSAIN, F - Institut National De La Recherche Scientifique (INRS)
item CHRISTOPHER, L - Oniris National Veterinary & Food Science School Of Nantes
item SALMIERI, S - Institut National De La Recherche Scientifique (INRS)
item LACROIX, M - Institut National De La Recherche Scientifique (INRS)

Submitted to: LWT - Food Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/4/2020
Publication Date: 7/7/2020
Citation: Begum, T., Follett, P.A., Hossain, F., Christopher, L., Salmieri, S., Lacroix, M. 2020. Microbicidal effectiveness of irradiation from Gamma and X-ray sources at different dose rates against the foodborne illness pathogens Escherichia coli, Salmonella Typhimurium and Listeria monocytogenes. LWT - Food Science and Technology. 132. https://doi.org/10.1016/j.lwt.2020.109841.
DOI: https://doi.org/10.1016/j.lwt.2020.109841

Interpretive Summary: Irradiation and plant essential oils have microbicidal effects against food-borne pathogens. The efficacy of a combination treatment with irradiation (cobalt-60 or x-rays at several different dose rates) and an oregano/thyme mixture was tested and shown to have higher efficacy than irradiation alone against Escherichia coli, Salmonella Typhimurium and Listeria monocytogenes. Both technologies have potential as a treatment for a wide variety of food products to improve food safety.

Technical Abstract: The radiation response of three foodborne illness pathogens was examined for irradiation with cobalt-60 Gamma and low-energy (125 keV) X-ray at different dose rates. Escherichia coli, Salmonella Typhimurium and Listeria monocytogenes were inoculated into rice and irradiated at target doses of 0 (control), 250, 500, 750, 1000, and 1500 Gy with either Gamma radiation (dose rates of 9.1, 3.9 or 0.22 kGy/h) or X-ray radiation (dose rate of 0.76 kGy/h). Doses were measured with traceability to national standards. The dose rate did not significantly affect D10 values (microbicidal effectiveness) for any of the Gamma-irradiated pathogens. Low energy X-ray irradiated pathogens had significantly higher D10 values (lower microbicidal effectiveness) for all pathogens compared to Gamma-irradiated pathogens. The combination of Gamma or X-ray irradiation with oregano/thyme essential oil (EO) fumigation generally increased the microbicidal effectiveness compared to irradiation alone. Gamma or low energy X-ray irradiation and plant essential oils such as oregano/thyme, applied alone or in combination, are effective antimicrobial treatments.