Effect of gamma-irradiation on thermoluminescence values in dried fruits

Studies were conducted to measure the effect of irradiation treatment on thermoluminescence (TL) values in dried fruits such as apricots, dates and raisins. For this purpose, inorganic dust particulate (minerals) adhering to the fruit surface was collected from untreated and treated (0.5, 1.0 and 1.5 kGy) samples. The TL responses of the isolated minerals was measured in the temperature range of 80-320 deg C at an increasing rate of 10 deg C/s. It was observed that peak of the TL signals appeared at 200 deg C in each case and generally the magnitude of the peak signals was almost 103 times that of unirradiated samples. Regression and correlation analysis of the data indicated strong relationship between radiation absorbed dose and TL values at each temperature (τ≥0.98). It was concluded that TL measurements could serve as a fast and reliable method for distinguishing as well as determining absorbed dose in irradiated dried apricot, date and raisin. (author)