Comparative Studies on Nutrient and Anti–nutrient Composition of Carrot (Daucus carota L.) and Cucumber (Cucumis sativus L.)

Abstract

Carrot (Daucus carota L.) and cucumber (Cucumis sativus L.) are underutilized root vegetable and fruit belonging to the Apiaceae and Cucurbitaceae family, respectively. A comparative study was carried out on proximate composition, amino acid profile and anti–nutritional factors of Daucus carota and Cucumis sativus. The proximate composition values (%) for Daucus carota and Cucumis sativus were found to be as follows: Moisture (5.06 and 4.39), ash (7.75 and 15.26), crude fat (6.09 and 4.83), crude fibre (13.04 and 18.25), crude protein (9.39 and 14.39) and carbohydrate by difference (58.67 and 42.90). The calculated fatty acids and metabolizable energy values were 4.87 and 3.86%; 1382.35 and 1152.64 kJ 100/g, respectively. The amino acid profiles revealed that Daucus carota and Cucumis sativus contained nutritionally useful quantities of most of the essential amino acids. The total amino acid (TAA), total essential amino acid (TEAA) (with His), total sulphur amino acid (TSAA) and essential aromatic amino acid (EArAA) for the Daucus carota and Cucumis sativus samples were 82.36 and 64.14; 22.93 and 30.11; 1.26 and 1.71; 2.13 and 2.66, respectively. However, supplementation of essential amino acids is required in a dietary formula based on the flour samples of Daucus carota and Cucumis sativus when comparing the EAAs in this report with the recommended FAO/WHO provisional pattern. The first limiting EAA in both samples was Met and Cys (TSAA). The antinutrient contents of Daucus carota and Cucumis sativus were also found to be as follows: Oxalate (241.67 and 142.45 mg/100 g), saponin (0.22 and 0.91%), alkaloids (2.85 and 2.23%), tannins (329.03 and 254.45 mg/100 g), cyanide (4.01 and 3.03 mg/100 g) and phytate (616.41 and 349.62 mg/100 g). These antinutritional factors have been shown to be deleterious to health or evidently advantageous to human and animal health if consumed at appropriate amounts.