Partial equilibration during dissolution of calcium hydrogen phosphate in aqueous sodium hydrogen citrate: mechanism behind spontaneous supersaturation increasing calcium bioaccessibility
Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt
Standard
Partial equilibration during dissolution of calcium hydrogen phosphate in aqueous sodium hydrogen citrate : mechanism behind spontaneous supersaturation increasing calcium bioaccessibility. / Liu, Xiao-Chen; Hansen, Jesper S.; Skibsted, Leif H.
I: European Food Research and Technology, Bind 248, 2022, s. 3015–3023 .Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Partial equilibration during dissolution of calcium hydrogen phosphate in aqueous sodium hydrogen citrate
T2 - mechanism behind spontaneous supersaturation increasing calcium bioaccessibility
AU - Liu, Xiao-Chen
AU - Hansen, Jesper S.
AU - Skibsted, Leif H.
N1 - Publisher Copyright: © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
PY - 2022
Y1 - 2022
N2 - The higher bioaccessibility of calcium from citrates compared to other salts, often explained by the capacity of hydroxycarboxylates like citrate spontaneously to form supersaturated calcium salt solutions, was analyzed using two models for dissolution of calcium hydrogen phosphate in aqueous sodium hydrogen citrate followed by slow precipitation of calcium citrate hexahydrate after a lag phase. During the dissolution calcium ion activity as measured electrochemically increased to a maximum plateau value for a dissolution time almost independent of initial hydrogen citrate concentration but with a supersaturation degree increasing strongly with increasing hydrogen citrate concentration. The difference in time dependence was analyzed by (i) a model assuming total equilibrium among the dissolved species, and (ii) a kinetic model based on coupled differential rate equations for transformations between involved dissolved species and precipitates using numerical integration. In contrast to model (i), model (ii) could quantify differences in time dependence of the concentration of dissolved species. A major difference was that the concentration of calcium hydrogen citrate follows the dynamics of the total calcium concentration in the equilibrium model, while the concentration decays monotonically towards an equilibrium value in the kinetic model. Calcium hydrogen citrate is concluded to be critical for the precipitation of dissolved calcium with the concentration of calcium hydrogen citrate determining the length of the lag phase and the rate of precipitation. Design of robust supersaturation for functional calcium foods and beverages should accordingly aim of minimizing the concentration of calcium hydrogen citrate.
AB - The higher bioaccessibility of calcium from citrates compared to other salts, often explained by the capacity of hydroxycarboxylates like citrate spontaneously to form supersaturated calcium salt solutions, was analyzed using two models for dissolution of calcium hydrogen phosphate in aqueous sodium hydrogen citrate followed by slow precipitation of calcium citrate hexahydrate after a lag phase. During the dissolution calcium ion activity as measured electrochemically increased to a maximum plateau value for a dissolution time almost independent of initial hydrogen citrate concentration but with a supersaturation degree increasing strongly with increasing hydrogen citrate concentration. The difference in time dependence was analyzed by (i) a model assuming total equilibrium among the dissolved species, and (ii) a kinetic model based on coupled differential rate equations for transformations between involved dissolved species and precipitates using numerical integration. In contrast to model (i), model (ii) could quantify differences in time dependence of the concentration of dissolved species. A major difference was that the concentration of calcium hydrogen citrate follows the dynamics of the total calcium concentration in the equilibrium model, while the concentration decays monotonically towards an equilibrium value in the kinetic model. Calcium hydrogen citrate is concluded to be critical for the precipitation of dissolved calcium with the concentration of calcium hydrogen citrate determining the length of the lag phase and the rate of precipitation. Design of robust supersaturation for functional calcium foods and beverages should accordingly aim of minimizing the concentration of calcium hydrogen citrate.
KW - Calcium citrate
KW - Equilibria during supersaturation
KW - Functional food
KW - Kinetic model
KW - Spontaneous supersaturation
KW - Supersaturation degree
U2 - 10.1007/s00217-022-04108-6
DO - 10.1007/s00217-022-04108-6
M3 - Journal article
AN - SCOPUS:85136914034
VL - 248
SP - 3015
EP - 3023
JO - European Food Research and Technology
JF - European Food Research and Technology
SN - 1438-2377
ER -
ID: 320869410