Comparative Nutrient Composition of Marine Crab and Shrimp from Seafood Market in Lagos State Nigeria

This study evaluated the proximate composition and mineral content of crabs and shrimps, highlighted their nutritional value and implications for human diets. The proximate composition showed that crabs had lower moisture content (9.58 ± 0.06%) compared to shrimps (13.5 ± 0.16%), indicating better storage stability and reduced microbial spoilage in crabs. On the other hand, the higher moisture content in shrimps enhanced their freshness but reduced shelf life without proper preservation. Shrimps had significantly higher fat content (8.24 ± 0.06%) than crabs (1.28 ± 0.08%), making them a rich source of omega-3 fatty acids, while crabs, with their lower fat profile, are suitable for those aiming to reduce fat intake. Ash content was higher in crabs (38.5 ± 0.07%) than in shrimps (14.7 ± 0.08%), reflecting their higher mineral content, particularly Calcium, Magnesium, and phosphorus. Protein content was higher in shrimps (49.9 ± 0.04%) than in crabs (32.4 ± 0.23%), making shrimps as an excellent source of high-quality protein. In terms of fiber, crabs had a higher amount (5.63 ± 0.28%) than shrimps (1.94 ± 0.06%), potentially offering digestive benefits. Carbohydrate content was similar in both species, with crabs at 12.6 ± 0.09% and shrimps at 11.8 ± 0.08%, contributing balanced energy. Mineral analysis showed that crabs had slightly higher Calcium (120 mg/kg) and Phosphorus (50 mg/kg) than shrimps (115 mg/kg and 45 mg/kg, respectively), while shrimps had higher iron content (75 mg/kg) compared to crabs (65 mg/kg), indicating their benefit for individuals with iron deficiency. Both species had comparable Magnesium levels (40–45 mg/kg). Heavy metals were low in both species, with Copper, Zinc, Cadmium, Lead, and Chromium concentrations within permissible limits, ensuring minimal toxicity risk. Overall, crabs are mineral-rich and low-fat, while shrimps provide higher protein and fat, making both valuable in addressing nutritional needs, particularly for protein and iron deficiencies.