Microencapsulated ferrous sulfate to fortify cow milk: absorption and distribution in mice

To determine the absorption and biodistribution of iron from microencapsulated ferrous sulfate (SFE-171), used to fortify dairy products with iron, a comparative study in four groups of 30 mice each was carried out. In two of the groups, the absorption of iron from ferrous ascorbate in water (13.3 +/- 4.3%) and from ferrous sulfate in water (12.7 +/- 3.9%) was determined and taken as reference standards. In the third group the iron absorption from SFE-171 in milk was determined, giving a value of 12.1 +/- 4.2%, which statistically does not differ from the data obtained with either reference standard. In the fourth group, the absorption of iron from ferrous sulfate in milk showed a value of 7.7 +/- 3.4%, which statistically differs with a p < 0.01 from the data corresponding to the other three groups. The biodistribution studies showed that the iron from the SFE-171 follows the same metabolic pathway as the iron from the reference standards thus, giving a higher radioactivity percentage and radioactivity concentration in organs or systems, principally blood, that are closely related to iron metabolism. Our studies allow us to conclude that the iron from SFE-171 in milk follows the same behavior as the nonhemic iron, with a higher absorption than that of ferrous sulfate in milk.