A specific but nevertheless simple real-time PCR method for the detection of irradiated food shown detailed at the example of garlic (Allium sativum)
Food irradiation is a process exposing food to ionizing radiations resulting in reduced storage losses, extended shell life and/or improved microbiological and parasitological safety of foods. Therefore, analytical methods are necessary to control irradiated food products by legal labs, ensuring enforcement of accurate labelling regulations. This publication describes a method for the specific detection of food which had been treated with ionizing radiations. The presented PCR method—working with endogenous DNA—is based on asymmetric PCR, where the two primers have different concentrations. The detection takes place with the aid of a TaqmanTM probe. The observed amplification efficiency, respectively, the obtained Ct values distinguish between irradiated and non-irradiated garlic samples. The detection limit can be estimated to approximatively 250 Gy. Experiments with heat treated garlic samples do not indicate a radiation treatment showing that this method is indeed specific for the detection of radiation treatment. As a conclusion, the presented real-time PCR method concerning the endogenous DNA is useful for sensitive and specific detection of irradiated garlic in routine analysis as well as a screening method.
KeywordsFood irradiation Garlic Real-time PCR Asymmetric PCR Screening
Compliance with ethical standards
Conflict of interest
We authors declare that we have no conflict of interest.
Compliance with ethics requirements
Our article does not contain any studies with human or animal subjects.
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