Effect of different doses of gamma irradiation on biochemical and microbiological properties of sesame (Sesamum indicum L.) seeds

Seed irradiation during storage processes is one of the most effective methods to improve the seeds quality. This investigation was carried out to determine the effects of the different doses of ionizing radiation on biochemical and microbiological properties of sesame seeds and oil. To determine these effects, seeds were exposed to radiation with different doses 3, 6, 9 and 12 kGyto time period of 207, 413, 620 and 826 min respectively. The results showed that gamma irradiation had no significant(p>0.05) effect on the different parameters. The ionizing radiation has no negative effect on the biochemical and microbiological quality of seeds and sesame oils. On the contrary, irradiation at different doses preserves the properties of sesame throughout the duration of storage While, smalldifferences, but sometimes significant (p<0.05), on protein and sugar contentswere recorded between irradiated and non-irradiated samples. The samples irradiated with the different doses (3, 6, 9 and 12kGy) preserved a great antioxidative activity, a high phenolic, flavonoids and protein content during the 12 months of conservation. Also, gamma radiation has ensured great stability throughout the experiment with regard to acidity and peroxide index. While, for the microbiological parameters, all the samples treated with the different doses remained completely free of bacteria at the end of storage period (after 12 months).