RESUMEN
Shelf-Life extension and improvement of the hygienic quality of the fish and its products, i.e., fresh, semidried and dried Tilapia nilotica fish, were achieved using gamma irradiation. The preparation of each product was described. Dose level of 3.5 kGy was the optimum and most effective dose for preservation of fresh eviscerated and headed fish. This dose was able to extend the shelf life of the Tilapia nilotica for 28 days at refrigeration temperature [3 +/- 1] a gainst only 7 days for unirradiated fish samples. Complete inhibition of non-spore forming pathogens contaminating the fish was achieved. Application of 5 kGy dose level appeared to be most effective for complete elimination of public health concern bacteria contaminating the semidried Tilapia nilotica fish samples and for considerable reduction of the total bacterial count, mould and yeast. This dose also extended the shelf-life of the semidried fish at ambient temperature up to 7 weeks. The same dose level of 5 kGy was effective for improving the hygienic quality of dried. Tilapia nilotica fish with 36% moisture content and 12% salt and of the fish. Packaging of drib fish in polyethylene bags [0.1 mm thickness] could protect the product from insect infesting during storage