Iron and zinc retention in common beans (Phaseolus vulgarisL.) after home cooking

Abstract

BackgroundAccording to the World Health Organization (WHO), iron, iodine, and Vitamin A deficiencies are the most common forms of malnutrition, leading to severe public health consequences. The importance of iron and zinc in human nutrition and the number of children found to be deficient in these nutrients make further studies on retention in cooked grains and cooked bean broth important.ObjectivesThis work aimed to evaluate iron and zinc retention in six common bean (Phaseolus vulgaris L.) cultivars under the following conditions: raw beans, regular pot cooking, pressure cooking, with and without previous water soaking, and broth.DesignDetermination of iron and zinc content in the raw, cooked bean grains and broth samples was carried out by Inductively Coupled Plasma (ICP) Optical Emission Spectrometry (Spectro Analytical Instrument – Spectroflame P). All experiments and analyses were carried out in triplicate.ResultsOverall, regardless of the cooking method, with or without previous water soaking, the highest zinc concentration was found in the cooked bean grains. However, pressure cooking and previous water soaking diminished iron retention in the cooked grains, while increasing it in the bean broth.ConclusionThe common bean was confirmed to be an excellent source of iron and zinc for human consumption, and it was suggested that beans should be consumed in a combined form, i.e. grain with bean broth.

Nutrition-sensitive interventions and programmes: how can they help to accelerate progress in improving maternal and child nutrition?

“…Results on bioconversion of β carotene to retinol in humans and bioavailability of zinc and iron from biofortifi ed compared with common varieties are very encouraging, suggesting that extra minerals will lead to net increases in quantities absorbed. Effi cacy studies also confi rm that intakes of iron-biofortifi ed rice 70 and beans 71,72 improve iron status, and that all biofortifi ed crops released so far have favourable agronomic qualities, including equal or higher yields than common varieties, and greater disease resistance and drought tolerance. Evidence regarding the eff ective ness of biofortifi cation, however, is still confi ned to vitamin A in orange sweet potato, and the scalability of delivery is yet to be shown.…”

Retention of proteins and minerals after cooking in cowpea genotypes1

“…Carvalho et al (2012) emphasize that the presence of phytates and tannins in plant fibers may negatively influence the availability of iron and zinc, as well as the cooking time. Lazarte et al (2015) observed that phytate levels promoted a significant decrease in the availability of calcium, iron and zinc, and suggested the immersion and fermentation of grains to improve the nutrient availability.…”

Modification of local diets to improve vitamin a, iron and protein contents for children aged 6 to 23 months in Kagera, Tanzania

“…2). Table 1) Carvalho et al, [26] reported that a food can be labeled as the 'source' of a nutrient when 100g of the product presents more than 15% of the dietary reference intake (DRI) for the desired nutrient. In 100g of food, all the modified complementary diets had more than 15% of the RDA for iron, vitamin A and protein.…”

“…These levels could meet the RDA's for breastfed and non-breastfed children. When a child consumes 500g of the modified dishes per day, she/he will meet the RDA of the nutrients [26].…”

“…Soaking of beans reduced time for cooking by 15.3-30.8 minutes and reduced antinutrients from 50-78%. The process also tended to increase absorption of minerals in legumes by 50-100% [16,[26][27][28][29]. In addition, soaking enhances the bioavailability of micronutrients and improving overall digestibility in plant-based diets [30].…”