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Studies on micellar calcium phosphate: composition and apparent solubility product in milk over a wide pH range

Published online by Cambridge University Press:  01 June 2009

Lesley C. Chaplin
Affiliation:
*National Institute for Research in Dairying, (University of Reading), Shinfield, Reading RG2 9 AT, UK

Summary

Calcium and phosphate concentrations in milk ultrafiltrate prepared at 37 °C over the pH range 4.0–8.0 have been measured and used to calculate the apparent solubility products for various calcium phosphates in milk. Micellar calcium phosphate had a constant Ca/Pi = 1·58·10·03 at all pH values and a near-invariant ion activity product for CaHP04. Apparent solubility products have also been obtained for brushite, hydroxyapatite and amorphous tricalcium phosphate in milk salt solution over a similar pH range. No evidence was found for a hydroxyapatite or amorphous tricalcium phosphate phase in milk.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1984

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References

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