ANALYSIS OF NUTRITIONAL COMPOSITION IN FLESH AND PEEL FROM DIFFERENT TYPES OF SWEET POTATO

Abstract

Sweet potato is an important food crop in many part of the world that provides essential nutrients although sweet potato peels, which may contain some nutrients are usually discarded. Therefore, this present investigation seeks to compare the nutritional potentials of peels and flesh from white, orange and purple skinned sweet potato. Proximate composition (Moisture, ash, protein, crude fat, crude fiber, total carbohydrates, total energy, Starch and Mineral content (Ca, Mg, K, P, and S) of three varieties of sweet potato was determined. The results were analyzed in (TWO Way ANOVA, SPSS software program). The nutritional values of three sweet potato varieties were significantly (p<0.05) varied due to cultivar variation, processing conditions and their interaction. Orange sweet potato variety contains the highest level of moisture 86.04- 81.64-g/100g, ash 5.52 g/100g and, 4.96g/100g, fiber 21.97-23.32g/100g, Magnesium 0.068- 0.094g/100g, in flesh and peel samples, and it‟s higher in sodium 0.087g/100g, phosphorus 0.059g/100g and starch 54.846 g/100g in flesh samples only. On the other hand, Purple sweet potato variety contains the highest level of carbohydrate 83.54- 65.72g/100g and Sulfur 0.523-0.86g/100g in both flesh and peels samples, while the highest value of Energy 350.66g/100g and Calcium 0.102g/100g in flesh samples only. While the White sweet potato variety contains the highest level of Protein 5.6- 8.85g/100g in both flesh and peel samples and potassium 0.542g/100g in flesh sample only. The result of this investigation showed that leaving the potato skin intact during processing may help to strengthen and confirm the possible role of sweet potato as a health promoting food and an alternative remedy for chronic diseases. Hence, this study would help for the consumers, dietitians and industrial policymakers for further use.