Published Article
A Study of Factors Affecting Iron Uptake from a Functionalized Hibiscus Beverage
Ade O Oyewole, Levente L Diosady
October 21, 2021
Iron deficiency accounts for over 50% of the world’s anaemia burden and it is widely prevalent in low- and middle-income countries. In response to the menace of iron deficiency in Sub-Saharan Africa, a commonly consumed beverage, the vibrantly red aqueous extract of the calyces of Hibiscus sabdariffa, has been functionalized. To determine the conditions that could potentially result in the most iron uptake by consumers of the functional beverage, the present study evaluated the effect of the factors that could influence the bioaccessibility of its iron content in the gastrointestinal (GI) tract.

Hibiscus beverage was fortified to contain, 6 mg iron per 250 mL of the beverage, by adding O.358 mM solution of ferrous sulphate salt to top up the native iron content determined to be 0.93±0.19 mg/ 250 mL. Also, a competing chelating agent - disodium EDTA was added to increase the bioaccessibility of iron from the beverage. Previous results showed the feasibility of releasing iron from the iron-polyphenol complex formed during the digestion of plant “foods”, with the addition of disodium EDTA.

The effect of changes in pH values of the beverage, to mimic different parts of the GI tract (pH 1.5 to 7.5 in incremental steps of 1), on the iron-polyphenol complex formed and the release of the iron with added disodium EDTA was investigated. Next, the molar concentration ratio of the iron to disodium EDTA was varied at 1:0, 1:1, 1:2 and 1:3 to evaluate the effect of the concentration of the competing chelating agent on the quantity of iron that was released. Absorbance peaks at 550 nm, corresponded to the iron-polyphenol complex formed. Complex formation that occurs at elevated pH was reduced by added disodium EDTA, indicating iron release, which made iron more bioaccessible. A 1:2 molar ratio of EDTA to iron gave the optimum increase in iron bioaccessibility from the Hibiscus beverage.
Hibiscus sabdariffa, iron bioaccessibility, iron deficiency
Suggested Citation
Oyewole AO, Diosady LL. A Study of Factors Affecting Iron Uptake from a Functionalized Hibiscus Beverage. (2021). LAPSE:2021.0790
Author Affiliations
Oyewole AO: University of Toronto
Diosady LL: University of Toronto
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CSChE Systems & Control Transactions
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Proceedings of the Canadian Chemical Engineering Conference 2021, October 24-27, Montréal, Québec, Canada
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Oct 21, 2021
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