Cooking Time and Iron Bioavailability: The USDA‐ARS Approach to Bean Fe Biofortification

Abstract

Beans (Phaseolis vulgaris L.) represent a significant portion of the diet for many populations at risk of Fe deficiency and are therefore a crop targeted for Fe biofortification. In Sub-Saharan Africa, 75% of the population use wood or charcoal as the primary cooking fuel; thus, the expense of cooking fuel factors heavily in selection of beans by consumers in this region prone to Fe deficiency. Our approach to bean Fe biofortification incorporates identifying and developing lines that are fast-cooking, acceptable to farmers and consumers, high in overall nutritional quality, and specifically high in bioavailable or bioaccessible (ie. “absorbable”) Fe as measured by an established Caco-2 cell bioassay. This approach is significant as this bioassay has now been thoroughly validated against animal studies and human efficacy studies of Fe biofortified crops. Application of the Caco-2 bioassay has recently resulted in the development of a Health and Nutrition Panel (HNP) to demonstrate the above approach. The HNP is composed of 12 cultivars refined from the screening of over 200 accessions from the Andean Diversity Panel. The HNP represents a defined set of lines that demonstrates how the fast-cooking trait can be associated with increased nutrition via increased bean consumption and via improved Fe bioaccessibility. The fast-cooking trait is highly tractable across multiple locations and harvest years. Fast cooking lines have the potential to save several hours of time and fuel. Such savings may allow for purchase of greater quantities of beans and thus increase bean consumption. As added benefit, increased Fe bioaccessibility also appears to be associated with the fast –cooking trait, and is particularly high in certain yellow bean varieties. Additional studies have shown that in direct comparison to high Fe lines of beans, some fast cooking yellow beans appear to deliver 2–3 times more absorbable Fe, even though they have lesser amounts of Fe. It is important to note that some of these fast cooking lines are already present in the African marketplace and are highly desired by consumers; however, they are not yet recognized for their nutrition potential. It is the goal of this program to fully characterize these lines, develop and continue breeding to enhance the fast-cooking and nutritional traits, and educate consumers of the nutritional benefits. Support or Funding InformationThis research funded by USDA-ARS. The Health and Nutrition Panel