Iron and zinc bioavailability in rats fed intrinsically labeled bean and bean-rice infant weaning food products

Beans are the core of the Latin American diet and contain iron and zinc. Ho wever, the bioavailability of these trace minerals from beans is low. The o bjective of this study was to determine if the bioavailability of iron and zinc could be improved with the use of fermentation and germination process ing technologies. Black beans native to Costa Rica were grown hydroponicall y with either radioactive iron or zinc. The influence of fermentation and g ermination on iron and zinc bioavailability from intrinsically labeled infa nt weaning food products based on black beans and beans-rice was determined in rats. Mineral bioavailability was determined using whole-body Fe-59 ret ention for iron, and whole-body Zn-65 retention and incorporation of radiol abel into bone for zinc. Percent absorption of 59Fe from fermented products ranged between 48.0 and 58.0. Percent absorption of 65Zn ranged from 57.0 to 64.0. Fermentation did not increase iron bioavailability in rats fed fer mented beans without rice. Fermentation of cooked beans significantly incre ased zinc retention. Germination significantly enhanced iron retention from cooked beans from 46 to 55% and from cooked beans-cooked rice from 34 to 4 8%. Germination significantly improved zinc absorption and retention from c ooked beans without added rice.