Edibility assessment of the swimming crab Charybdis natator (Brachyura: Portunidae) from the Gulf of Suez, Red Sea, Egypt

Abstract

he portunid crab Charybdis natator exists in the commercial catches of the Gulf of Suez trawlers in a considerable quantity. Although edible worldwide, this crab is hardly known among local consumers. This study aimed to assess the suitability of this crab as food. Examination of the muscle tissues was carried out in terms of biochemical composition (protein, lipids and carbohydrates) and the accumulation of the heavy metals (Cd, Cu, Fe, Pb and Zn). Organoleptic differences among the cooked meat of this species and that of the popular species Portunus pelagicus were tested. Protein constituted over 80% of the muscles dry weight of male and female crab, followed by lipids (7.25-7.79%) and carbohydrates (5.39-6.26%) respectively. Zn was the highest accumulated metal (46.6, 45.4ppm) followed by Cu (24.4, 36.6 ppm), Fe (21.8, 36.2 ppm) and Pb (3.9, 4.6ppm), while Cd was the lowest (0.9ppm) in males and females respectively. Intra-specific and size-based variations in metal uptake were recorded. Test of organoleptic qualities ranked P. pelagicus as higher in all attributes. However, no significant difference was observed in the total acceptability of the two species (P≥ 0.05). The study highlighted the suitability of C. natator as edible, nutritive and safe seafood.