Nutritional evaluation of leafy vegetables of Corchorus olitorius family from Ekiti State, Nigeria

Abstract

Proximate composition, mineral contents, anti-nutritional factors as well as non-starch polysaccharide components of three varieties of a commonly  consumed leafy vegetable: Corchorus olitorius; Sooro var., Amugbadu var. and Oniyaya var. were investigated using standard analytical  techniques. The levels of fat content were low, ranged at 1.98-2.22g/100g. The results of crude fibre (11.2-12.9g/100g) and crude protein  (17.5-29.6g/100g) in this study were higher than the range reported for most Nigerian leafy vegetables. Mineral analysis results showed that the  samples were good sources of essential minerals especially potassium and iron while non-nutritive/toxic minerals were contained in trace amounts.  The result of both mineral ratios and mineral safety index showed that the Corchorus olitorius varieties could not pose any health risk for the  consumers. Phytate had the highest concentrations (5.30-6.10mg/100g) representing 43.10-68.2% of the total anti-nutritional factors. However, anti-  nutrients levels were generally low in this study. Phy:Zn (0.424) and [CA][Phy]/[Zn] (0.049) molar ratios showed that only Sooro would promote Zn  bioavailability. Compositions of non-starch polysaccharides were generally low with neutral detergent fibre (NDF) having the highest concentration  in each of the samples. Statistical analysis showed that there were no significant differences among the samples in most of the determinations  except PEP %, K, Ca, Mg and [phy]:[Zn].