Determination of The Shelf Life of some Marine Fishes (plectropomus maculatus, epinevolatile nitrogen test

Abstract

This study was carried out to evaluate the impact of temperature, spoilage ratios, and the optimum period for keeping the refrigerated products. The stu died samples included (Najil) Plectropomus maculatus, (Hamoor) Epinephelus areolatus and( Shouar) Lethrinus spp were collected from commercial sale point at Khartoum center. The three samples were transferred to laboratory and kept at 40C and then a total volatile basic nitrogen (TVB-N) test was performed to assess the spoilage of products under study. The test was carried in the first day and repeated once every five days. The results were as follows: The total volatile basic nitrogen (TVB-N) ratio in the first two species (Najil, Hamour ) reached the recommended limit (30mg/100g) in twenty five days period, while the third species (Shouar ) reached the recommended limit in twenty days. This difference in the period of acceptability might be attributed to the difference in the nutritional contents of the samples, the rate of fats available in them, or may be due to bad handling after harvesting. The results showed that there is no significant difference between the (Najil) fish and (Hamour) spp (P< 0.05) while it appeared in the third one (Shouar) (P> 0.05). 7 The study showed that the expiry period of the fishery products, especially Najil, Hamoor and Shouar when kept at 40C range between 20-25 days which complys with Europe Unite (EU) standard widely used in many world countries.