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pH-Induced dissociation of bovine casein micelles. II. Mineral solubilization and its relation to casein release

Published online by Cambridge University Press:  01 June 2009

Douglas G. Dalgleish  and
Andrew J. R. Law
Douglas G. Dalgleish
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK
Andrew J. R. Law
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, UK
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Summary

Measurements of the release of Ca, Mg and inorganic phosphate(Pi) from the casein micelles of bovine milk have been made, as functions of the pH, in the range 4·9–6·7, and at temperatures of 4, 20 and 30 °C. The results are in general agreement with earlier published studies in giving a value of 1·75–1·84 for the micellar Ca:Pi ratio. Mg appeared to behave similarly to Ca, although the amounts of micellar material were much smaller. The results on the acid-solvation of calcium phosphate are considered in relation to published quantitative studies of the pH-induced dissociation of the different types of caseins from the micelle, and of the micellar dissociation caused when micellar calcium phosphate is dissolved at neutral pH. It is evident from this that at present it is not possible to derive a universal relation between the dissociation of minerals and of caseins from the micelles at different temperatures and under different conditions.

Type
Original articles
Information
Journal of Dairy Research , Volume 56 , Issue 5 , November 1989 , pp. 727 - 735
Copyright
Copyright © Proprietors of Journal of Dairy Research 1989

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References

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