Effect of household processing on the in vitro bioavailability of iron in mungbean (Vigna radiata)

Mungbean (Vigna radiata) is a major source of energy and protein in developing countries, especially for the vegetarian population. Improvement of the bioavailability of iron in mungbean by common household processes could make a significant contribution to the nutrition of people in countries where iron-deficiency anemia is widespread.

The study was conducted to determine the effect of common household processes on nutritional and antinutritional factors as well as in vitro bioavailability of iron in mungbean.

Mungbean was subjected to various domestic processes such as dehulling, pressure cooking, germination, and fermentation. The effects of these processes on proximate composition, antinutritional factors (phytin phosphorus, polyphenols, and neutral detergent), and iron, including ionizable iron, were determined.

No significant change in crude protein content was observed. There was a significant (p < or = .05) increase in fiber content after germination. Ash content decreased significantly (p < or = .05) after all processing methods. The processing methods resulted in a significant (p < or = .05) reduction in phytin phosphorus and polyphenols. Pressure cooking significantly (p < or = .05) decreased the neutral detergent fiber, whereas fermentation and germination increased it. The phytate:iron molar ratio of processed mungbean revealed that the maximum reduction was in germinated and fermented samples. Ascorbic acid content increased significantly (p < or = .05) after germination. The in vitro bioavailability of iron in raw mungbean was 7.32%. All of the processing methods resulted in an increase in iron bioavailability in vitro; the maximum bioavailability was in germinated cooked mungbean (12.52%), followed by fermented cooked mungbean and germinated raw mungbean (both 11.04%).

Suitable processing techniques can improve the in vitro bioavailability of iron from mungbean. If mungbean products with enhanced iron bioavailabilty are developed, they could help improve the iron status of the population.