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ARS Home » Northeast Area » Ithaca, New York » Robert W. Holley Center for Agriculture & Health » Plant, Soil and Nutrition Research » Research » Publications at this Location » Publication #377675

Research Project: Advancing the Nutritional Quality of Staple Food Crops for Improved Intestinal Function and Health

Location: Plant, Soil and Nutrition Research

Title: Impact of Ascorbic acid on the in vitro Iron Bioavailability of a casein-based Iron Fortificant in comparison to Ferrous Sulfate and Ferric Pyrophosphate

Author
item SABATIER, MAGALIE - Nestle
item RYTZ, ANDREAS - Nestle
item DUBASCOUX, STEPHANIE - Nestle
item NICOLAS, MARINE - Nestle
item DAVE, ANANT - Massey University
item SINGH, HARJINDER - Massey University
item BODIS, MARY - Cornell University - New York
item Glahn, Raymond

Submitted to: Nutrients
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/9/2020
Publication Date: 9/11/2020
Citation: Sabatier, M., Rytz, A., Dubascoux, S., Nicolas, M., Dave, A., Singh, H., Bodis, M., Glahn, R.P. 2020. Impact of Ascorbic acid on the in vitro Iron bioavailability of a casein-based iron fortificant in comparison to ferrous sulfate and ferric pyrophosphate. Nutrients. 12(9):2776. https://doi.org/10.3390/nu12092776.
DOI: https://doi.org/10.3390/nu12092776

Interpretive Summary: A new iron -casein complex (ICC) has been developed for iron (Fe) fortification of dairy food products. The objective was to assess the impact of ascorbic acid (AA) on iron bioavailability of the ICC versus common Fe compounds such as ferrous sulfate (FeSO4) and ferric pyrophosphate (FePP). A cell culture bioassay for Fe bioavailability was used to compare the samples. The study showed that iron from ICC was similar in bioavailability to Festo4 and higher than FePP. Similar to FeSO4, uptake of Fe from ICC was enhanced in the presence of AA. Given this effect, it can be concluded that ICC provides an excellent source of iron.

Technical Abstract: A new iron -casein complex (ICC) has been developed for iron (Fe) fortification of dairy matrices. The objective was to assess the impact of ascorbic acid (AA) on its in vitro bioavailability in comparison with ferrous sulfate (FeSO4) and ferric pyrophosphate (FePP). A simulated digestion coupled with the Caco-2 cell culture model was used with in parallel solubility and dissociation tests. Under diluted acidic conditions, the ICC was as soluble as Festo4, but only part of the iron was found to dissociate from the caseins, indicating that ICC is an iron chelate. The Caco-2 cells results in milk showed that, the addition of AA (2:1 molar ratio) enhanced iron uptake from the ICCs to a similar level to that from FeSO4 (p = 0.582; p = 0.852) and to a significantly higher level than that from FePP (p < 0.01). This translated into a relative in vitro bioavailability to FeSO4 of 36% for FePP and 114 and 104% for the two ICCs. Similar results were obtained from water. Increasing the AA to iron molar ratio (4:1 molar ratio) had no additional effect on the ICCs and FePP. However, ICCs absorption remained similar to that from FeSO4 (p = 0.666; p = 0.113), and was still significantly higher than that from FePP (p < 0.003). Therefore, even though iron from ICC does not fully dissociate under gastric digestion, iron uptake suggested that ICCs are absorbed to a similar amount as FeSO4 in the presence of AAICCs thus provide an excellent source of iron.