Some microbial, chemical and sensorial properties of gamma irradiated sesame (Sesamum indicum L.) seeds

• Sesame seeds were treated with gamma irradiation and stored fore 12 months.
• Gamma irradiation had no significant approximate composition of seeds.
• Acidity decreased, while volatile basic nitrogen increased due to irradiation.
• Gamma irradiation reduced the microorganisms of sesame seeds.
• The effect of gamma irradiation on sensorial properties were negligible.

The effect on microbial, chemical and sensorial properties of sesame seeds was determined after irradiation and storage. The sesame seeds were analyzed before and after irradiation with 3, 6 and 9 kGy of gamma irradiation, and after 6 and 12 months of storage. The results showed that gamma irradiation had no significant (p > 0.05) effect on the moisture, ash and fat content on sesame seeds. While, small differences, but sometimes significant (p < 0.05), on protein and sugar contents were recorded between irradiated and non-irradiated samples. Total acidity percentage decreased significantly (p < 0.05), while total volatile basic nitrogen (TVBN) increased significantly (p < 0.05) due to irradiation. During storage, total acidity increased (p < 0.05) and TVBN decreased (p < 0.05). Gamma irradiation reduced the microorganisms of sesame seeds. Samples treated with 3 kGy or more remained completely free of fungi throughout the storage. While, only the samples treated with 9 kGy remained completely free of bacteria at the end of storage period (after 12 months). The scores for taste, flavor, color and texture of irradiated samples were higher, but not significantly (p > 0.05) than those of non-irradiated samples.