Irradiation of dates: insect disinfestation, microbial and chemical assessments, and use of thermoluminescence technique

Irradiation of dates (Khalas variety) at 0.9 kGy was sufficient to eliminate single insect infestation ( Oryzaephilus surinamensis) and mixed infestation ( O. surinamensis and Tribolium castaneum), whereas 0.3 kGy was effective only in controlling single infestation. Sensory properties were not affected but irradiation contributed to some reduction in microbial counts immediately after irradiation and counts remained low till the end of 6 months storage period. All sugars were significantly reduced immediately after irradiation but they increased gradually with increasing storage time. Thermoluminescence (TL) technique was useful in discriminating between irradiated and unirradiated dates during the entire storage period but was less sensitive as far as the dose estimation is concerned.