TOTAL AND SOLUBLE IRON CONTENT AND EFFECT OF CERTAIN INHIBITORS PRESENT IN SELECTED VARIETIES OF TEPARY BEAN (PHASEOLUS-ACUTIFOLIUS)

Seven varieties of tepary bean (Phaseolus acutifolius) were evaluated for their total iron content, soluble iron content, and content of absorption inhibitors, such as tannins, phosphates, oxalates, and crude fiber. The mean total iron content of tepary bean determined by atomic absorption spectrophotometry was 7.59 +/- 0.5 mg/100 g (dry weight basis) and was higher than the mean total iron content of pinto bean (Phaseolus vulgaris) (5.83 mg/100 g). The mean soluble iron content of tepary beans estimated in vitro was 0.7 mg/100 g and was higher compared to that of pinto beans (0.23 mg/100 g). Tannins, oxalates, and phosphates affected the iron solubility in tepary beans. Iron solubility was not affected by crude fiber.