Comparative Characterization of the Nutritional Profiles of Cocoyam (Colocasia esculenta) Corm and Three-Leaf Yam (Dioscorea dumetorum) Tuber

Abstract

Malnutrition has been a problem globally, due to limited awareness of the nutritional value of cultural staple foods. Cocoyam (Colocasia esculenta) and three-leaf yam (Dioscorea dumetorum) are highly consumed in Nigeria, with selection usually based on taste and availability with less consideration on nutrient composition. Proximate composition and vitamin content of both species were analyzed for their nutritional differences using standard methods. C. esculenta recorded higher values for moisture (10.53 ± 0.02 %), ash (3.19 ± 0.03 %), crude protein (5.22 ± 0.01 %), crude fiber (1.90 ± 0.03 %), and crude fat (1.46 ± 0.02 %) compared to D. dumetorum (moisture: 9.72 ± 0.03%, ash: 2.37 ± 0.01%, crude protein: 4.27 ± 0.10%, crude fat: 1.57 ± 0.02%). However D. dumetorum had significantly higher total carbohydrate (81.44 ± 0.08 %) than C. esculenta (77.70 ± 0.06%). Vitamin levels were greater in D. dumetorum - vitamin A (3.74 ± 0.03 µg/g), vitamin C (8.63 ± 0.04 mg/100 g), vitamin E (0.64 ± 0.01 mg/100 g), vitamin B1 (0.24 ± 0.01 mg/100 g), vitamin B2 (0.17 ± 0.02 mg/100 g), and vitamin B3 (2.76 ± 0.04 mg/100 g) compared to C. esculenta (vitamin A: 2.68 ± 0.01 µg/g; vitamin C: 7.41 ± 0.03 mg/100 g; vitamin E: 0.53 ± 0.00 mg/100 g; vitamin B1: 0.19 ± 0.01 mg/100 g; vitamin B2: 0.13 ± 0.02 mg/100 g; vitamin B3: 1.68 ± 0.03 mg/100 g). C. esculenta is richer in proximate nutrients, while D. dumetorum contains more vitamins. Given its lower carbohydrate content, which may have lower glycemic index, C. esculenta is recommended for the elderly and diabetic patients, whereas D. dumetorum may be more suitable for younger generation.