This disclosure provides materials and methods for improving the nutritional value of food products by increasing the content of chelated iron. Heme binding proteins (designated as PX90 proteins) that have not previously been used as food additives are manufactured by recombinant expression, and then included in food products during manufacture or preparation. PX90 proteins may also impart a meat-like flavor or aroma, either coincidentally or by design. Subcategories of PX90 proteins are structurally related to THAP4-like heme-binding beta-barrel domain containing proteins, indoleamine 2,3-dioxygenase (IDO), DyP-type peroxidase, ferritins, and hemopexins. The bioavailable iron in nutritional supplements and food products of this disclosure is especially beneficial for consumers who have manifestations of iron deficiency, low blood hematocrit, anemia, and other hematological abnormalities.

This disclosure provides materials and methods for improving the nutritional value of food products by increasing the content of chelated iron. Heme binding proteins (designated as PX90 proteins) that have not previously been used as food additives are manufactured by recombinant expression, and then included in food products during manufacture or preparation. PX90 proteins may also impart a meat-like flavor or aroma, either coincidentally or by design. Subcategories of PX90 proteins are structurally related to THAP4-like heme-binding beta-barrel domain containing proteins, indoleamine 2,3-dioxygenase (IDO), DyP-type peroxidase, ferritins, and hemopexins. The bioavailable iron in nutritional supplements and food products of this disclosure is especially beneficial for consumers who have manifestations of iron deficiency, low blood hematocrit, anemia, and other hematological abnormalities.