Comparative studies between fumigation and irradiation of semi‐dry date fruits

This experiment was carried out on Egyptian semi‐dried date fruits “El‐Seidi CV.” which are used to process paste of dates. It is aimed to compare the effect of irradiation (1.5, 3.0 kGy) and fumigation with methyl bromide (MB) on physical, chemical and mycological characters, especially production of aflatoxins during storage of the dates for long time (8 months). Irradiation was more effective in de‐infestation of dates than MB, but caused significant loss in weight of dates. No significant changes were observed in irradiated samples as well as in MB samples for moisture content, pH‐values and titratable acidity, but significant changes were observed in browning and sugars, either total, reducing, non reducing or sugar/acid ratio. Irradiation (3.0 kGy) was more effective than other treatments for inhibition of the growth of fungi and prevention of aflatoxin production in synthetic broth media or date fruits. Therefore, irradiation dose (3.0 kGy) can be recomended to use than fumigation (MB) to keep date fruits with good quality, free from infestation, contamination and more safe for human consumption during long storage period.