Proximate and mineral elements composition of five locally consumed fruits in Kano State, Nigeria

Abstract

A number of tropical fruits are cultivated in almost all parts of northern Nigeria with high nutritional value that plays important role in human nutrition. This study was aimed at evaluating the proximate and mineral element composition of the five tropical fruits (Shea-fruit, Mango, Guava, Water melon and Orange) that are widely consumed in Kano state Nigeria. The proximate composition of the studied fruits were determined by the standard methods of Official Analytical Chemists, while the Mineral Elements (Ca and Mg) were analyzed using Atomic Absorption Spectrophotometry. The levels of Na⁺ and K⁺ were determined using Flame photometry and the level of P was determined by Vanadomolybdate method. The result of the proximate analysis shows that water melon has the highest moisture and protein contents (95.3±0.7% and 7.7±0.8% respectively). Shea fruit recorded the highest ash, lipid and energy value (7.35±0.5%, 2.12±0.8% and 1516.7±8KJ/100g respectively). Orange has the highest available carbohydrate (86.54±1.7%) while mango has the highest fiber content (13.52±0.2%) among the studied fruits. Similarly, Concentration of Ca was found to be highest in the pulp of orange (0.277±0.025mg/100g). The levels Mg were found to be highest in the peel of water melon (30.0±0mg/100g). More so, the levels of K and P were highest in the peel  and pulp of guava (138.9±4.8mg/100g and 48.6±0.2mg/100g respectively) with  significant  difference (p<0.05) between  the studied segments of the fruit. The level of Na was found to be highest in the peel of mango (6.7±0.7mg/100g). The results obtained show that the studied samples of fruits are rich in total protein, available carbohydrate and crude fiber. Likewise, the fruits also have appreciable amounts of K, Mg, Na and P but poor sources of Ca. Hence, consumption of such fruits could improve the nutritional status of the consumers.

Keywords: Fruits, Proximate, Mineral, Atomic Absorption Spectrophotometry, Flame Photometry