ABSTRACT
Aims: In tropical Africa, leafy vegetables are traditionally cooked and eaten as a relish together with a starchy staple food. The current study aimed to evaluate the influence of boiling on bioactive, proximate and antinutrients compounds in Solanum nigrumleaves. Methodology:The leaveswere subjected to boiling in pressure cooker for 10, 15 and 20 min and proximate composition, minerals, nutritive and anti-nutritional components were determined according tostandard methods for nutritional guidelines.Results:The result of the study revealed that longer time of boiling (higher than 10 min) caused negative impact by reducing nutritive value but positive impact by reducing anti-nutrients. The registered losses (p < .05) at 10 min were as follows: ash (12.37%), proteins (33.69%), vitamin C (11.23 mg/ 100 g), polyphenols (125.41 mg/ 100 g) Tannins (81.96 mg/ 100 g) and Flavonoids (14.03 mg/100 g). The average increase of fibers content was (39.41%). Furthermore, after 10 min of boiling time the residual contents (p<0.05) of minerals was:Calcium (1079±29.04 to 386±78 mg/ 100 g), Phosphorus (405..24±10-508.88±2.58 mg/ 100 g), Iron (33.48±0.93–44.50±1.23 mg / 100 g) and Magnesium (572.78±19.76–662.99±27.23 mg/ 100g).The antinutrient composition for oxalic acid were ranged 72.61±6.29 to 223.67±6.35 mg/100 g. The different ratios sodium / potassium (<1) and oxalates/calcium (<2.5) were under the respective critical value for all boiling. Conclusion:These results suggest that the recommended time of domestic cooking must be less than 10 min for the studied leafy vegetables in order to contribute efficiently to the nutritional requirement and to the food security of Ivorian population.
ABSTRACT
Aims:Leafy vegetables play an important role as essential components of diet for rural populations in tropical Africa. The aim of this study was to evaluate the nutritive value of two leafy vegetable species (Corchorus olitorusand Hibiscus sabdariffa) consumed widely as sauces in Côte d’Ivoire.Methodology:The proximate composition, minerals, nutritive and anti-nutritional components of fresh leafy vegetables were determined according to standard methods for nutritional guidelines Results:The results obtained were as follows: moisture (85.75 -86.29% Fresh basis), proteins (13.13 -21.00% Dry basis), ash (7.00 -9.14% Dry basis), carbohydrates (26.03 -42.97% Dry basis) and lipids (4.35 -4.74% Dry basis). The mineral contents were Phosphorus (0.44 –0.62 g/100 g), Calcium (0.71 –1.41g/100g), Magnesium (1.31 –2.00 g/100g), and high amount of Iron (4.96 –5.41 g/100g). The result of computed antinutrient to mineral molar ratios suggest that Iron and Calcium bioavailability may not be impaired when the two leafy vegetables were consumed. These leafy vegetables were good sources of polyphenols (80.00 -103.00 mg/100g).Conclusion:The leaves of Corchorus olitorusand Hibiscus sabdariffa contain appreciable amount of nutrients and minerals which could participate in the maintenance of a good nutritional status of the people in Côte d’Ivoire