Cereal Chem 53:78 - 84.  |  VIEW ARTICLE
Selection of Iron Sources for Cereal Enrichment.

B. N. Harrison, G. W. Pla, G. A. Clark, and J. C. Fritz. Copyright 1976 by the American Association of Cereal Chemists, Inc. 

Most cereal enrichment is accomplished with ferrous sulfate, reduced iron, ferric orthophosphate, or sodium iron pyrophosphate. Selection must be based on bioavailability, technological feasibility, and cost. Ferrous sulfate is the standard against which other iron sources should be compared for bioavailability. Great variation was found among samples of reduced iron and ferric orthophosphate. A sample of electrolytic iron was separated into fractions 7-10 micrometers and 27-40 micrometers. Relative biological value (RBV) of the finer was 68-75; that of the coarser was 27-29. Five samples of ferric orthophosphate had RBVs of 6-46. RBV was positively correlated with solubility in 0.1N HCl and negatively with particle size. Eighteen samples of unbleached white flour were enriched with different sources and levels of iron and stored in sealed containers. An untrained panel detected rancidity by smell in samples enriched with ferrous sulfate after 4 days at 50 C and after 11 to 28 days in samples with reduced iron. All samples stored at a constant temperature of 23 +/- 3 C were acceptable after 24 months' storage.