Applied nutritional investigationPotential contribution of African green leafy vegetables and maize porridge composite meals to iron and zinc nutrition

- This study investigated the mineral nutritional value of green leafy vegetable (GLV) dishes and composite and maize porridge meals.
- GLV dishes contained average amounts of zinc, but were high in both iron and antinutrients.
- Compositing the GLV dishes with fortified maize porridge decreased the iron and zinc contents.
- The low antinutrient content of the maize porridge, led to increased amounts of bioaccessible iron and zinc in the meals.

ObjectivesThe aim of this study was to determine the mineral nutritive value of different traditional African green leafy vegetable (GLV) dishes and their composite meals with fortified and unfortified maize porridge.MethodsThe mineral (iron, zinc, and calcium) and antinutrient (phytate, total phenolics, and tannins) contents and in vitro bioaccessibility of iron and zinc were analyzed. The iron and zinc contents and bioaccessibilities were used to calculate contribution these dishes and meals could make toward the recommended daily requirements and absolute requirements of vulnerable populations.ResultsIt was found that the GLV dishes contained average amounts of zinc (2.8-3.2 mg/100 g, dry base [db]), but were high in both iron (12.5-23.4 mg/100 g, db) and antinutrients (phytate 1420-2089 mg/100 g, db; condensed tannins 105-203 mg/100 g, db). The iron bioaccessibility and amount of bioaccessible iron ranged between 6.7% and 45.2% and 0.9 and 5.11 mg/100 g, db, respectively. The zinc bioaccessibility and amount of bioaccessible zinc ranged between 6.4% and 12.7% and 0.63 and 1.63 mg/100 g, db, respectively.ConclusionImportantly, although compositing the GLV dishes with fortified maize porridges decreases the iron and zinc contents, because of the low antinutrient content of the maize meal, the amount of bioaccessible iron and zinc in the meal increases.