Nutritional evaluation of the peels from Citrullus lanatus and Manihot esculenta, an insight into the conversion of waste to food

Abstract

Background: Huge quantity of cassava and watermelon wastes are daily discharged to the environment with unwholesome consequences. Therefore, research into the effective utilization of these agricultural by-products is of global interest. Methods: The present study evaluated the proximate, minerals, and amino acid compositions of cassava and watermelon peels using standard procedures. Results: The results revealed that carbohydrate is the most abundant proximate contents of both the cassava (82.14±0.42%) and watermelon (62.58±0.78%) peel, followed by crude fiber (5.51±0.06% and 18.90±0.04%), moisture (8.31±0.04% and 5.20±0.07%), crude ash (1.25±0.03% and 7.25±0.04%) for cassava and watermelon peels respectively, while crude fat (0.98±0.03% and 3.92±0.06%) is the least abundant proximate in both samples. Magnesium is the most abundant mineral contents of both the cassava (79.50±4.45Mg/100g) and watermelon (75.53±3.70Mg/100g) peel, followed by sodium (62.35±0.79 Mg/100g and 52.24±3.24 Mg/100g), potassium (22.12±1.34 and 32.65±2.01 mg/100g) for cassava and watermelon peels respectively while copper (0.73±0.05 Mg/100g and 0.67±0.64 Mg/100g) was the least abundant minerals in both samples. The total amino acid compositions of 66.31±4.56 g/100g and 41.80±2.68 g/100g were recorded for cassava and watermelon peel. Glutamic acid (9.96±0.06g/100g) and leucine (4.03±0.05 mg/100g) the most abundant amino acid in cassava and watermelon seed respectively. Conclusion: In conclusion, the peels of cassava and water melon examined, have appreciable levels of nutrients compositions that can be incorporated into human and animal feed formulation.