Abstract
Photostimulated luminescence (PSL) and thermoluminescence (TL) analyses were performed to identify commercially-irradiated potatoes. Increased PSL levels were observed in irradiated potatoes, regardless of their origin: the integrated photon counts (PCs) of untreated potatoes grown in 9 different fields ranged between −303 and 9194, whereas those for potatoes irradiated at 50 Gy were 23107 counts or more. Although the PSL from irradiated potatoes declined after exposure to room light, the PSL of ≥ 50-Gy-irradiated potatoes was stable after 4 months of storage in the dark. The integrated net PCs ranged from 41868 to 127226 counts in the commercially-irradiated potatoes (n = 10) after 2 months of storage. These results indicate that PSL analysis of the potato surface is useful for confirming the irradiation history before sale at a retail shop. TL analysis of potato surface soils enabled identification of commercially irradiated potatoes even after exposure to room light.
