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Size distribution and average size parameters of casein micelles determined by electron microscopy in bovine milk between pH 5·5 and 6·7. A comparison of several evaluation methods

Published online by Cambridge University Press:  01 June 2009

Henk J. Vreeman ,
Bas W. van Markwijk  and
Paula Both
Henk J. Vreeman
Affiliation:
Netherlands Institute for Dairy Research (NIZO), PO Box 20, 6710 BA Ede, The Netherlands
Bas W. van Markwijk
Affiliation:
Netherlands Institute for Dairy Research (NIZO), PO Box 20, 6710 BA Ede, The Netherlands
Paula Both
Affiliation:
Netherlands Institute for Dairy Research (NIZO), PO Box 20, 6710 BA Ede, The Netherlands
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Summary

The conversion of the two-dimensional size distribution of casein micelles, observed by electron microscopy in a plane section, to the three dimensional distribution is discussed and the average size parameters evaluated by several methods are compared. It is shown that parameters containing the −1 moment of the two-dimensional distribution, i.e. Dn, the number of micelles per unit volume and the width of the size distribution, are sometimes uncertain. The occurrence of negative numbers in some of the classes of the distribution is discussed and remedies are suggested. Sections were made by freeze-fracturing skim milk samples; the pH of the milk was between 5·5 and 6·7.

Type
Original Articles
Information
Journal of Dairy Research , Volume 58 , Issue 3 , August 1991 , pp. 299 - 312
Copyright
Copyright © Proprietors of Journal of Dairy Research 1991

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References

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