Hostname: page-component-745bb68f8f-lrblm Total loading time: 0 Render date: 2025-01-09T03:10:08.095Z Has data issue: false hasContentIssue false
  • English
  • Français

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
Get access Rights & Permissions [Opens in a new window]

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Bach, G. 1903 [The determination of characteristic sizes of sphere distribution by measuring diameters in a section.] Zeitschrift für Wissenschaftliche Mikroskopie 65 285–291Google Scholar
Bach, G. 1905 [The determination of characteristic sizes of sphere distribution from incomplete distribution of diameters in a section.] Metrika 9 228–233CrossRefGoogle Scholar
Buchheim, W., Lund, S. & Scholtissek, J. 1989 [Comparative studies on the structure and size of casein micelles in milk from different species.] Kieler Milchwirtschajtliche Forschungsberichte 41 253–265Google Scholar
Dewan, R. K., Chudgar, A., Mead, R., Bloomfield, V. A. & Morr, G. V. 1974 Molecular weight and size distribution of bovine milk casein micelles. Biochimica et Biophysica Acta 342 313–321CrossRefGoogle ScholarPubMed
Donnelly, W. J., McNeill, G. P., Buchheim, W. & McGann, T. C. A. 1984 A comprehensive study of the relntionship between size and protein composition in natural bovine casein micelles. Biochimica et Biophysica Acta 789 136–143CrossRefGoogle Scholar
Goldsmith, P. L. 1967 The calculation of true particle size distributions from the sizes observed in a thin slice. British Journal of Applied Physics 18 813–830CrossRefGoogle Scholar
Griffin, M. C. A. & Anderson, M. 1983 The determination of casein micelle size distribution in skiin milk by chromatography and photon correlation spectroscopy. Biochimica et Biophysiea Acta 748 453–459CrossRefGoogle Scholar
Holt, C. 1985 The size distribution of bovine casein micelles: a review. Food Microstntclure 4, 1–10Google Scholar
Holt, C., Kimber, A. M., Brooker, B. & Prentice, J. H. 1978 Measurements of the size of bovine casein micelles by means of electron microscopy and light scattering. Journal of Colloid and Interface Science 65 555–565CrossRefGoogle Scholar
Horne, D. S. 1984 Determination of the size distribution of bovine casein micelles using photon correlation spectroscopy. Journal of Colloid and Interface Science 98 537–548CrossRefGoogle Scholar
Lin, S. H. C., Dewan, R. K., Bloomfield, V. A. & Morr, C. V. 1971 Inelastic light-scattering study of the size distribution of bovine milk casein micelles. Biochemistry 10 4788–4793CrossRefGoogle ScholarPubMed
McGann, T. C. A., Donnelly, W. J., Kearney, R. D. & Buchheim, W. 1980 Composition and size distribution of bovine casein micelles. Biochimica et Biophysica Acta 630 261270CrossRefGoogle ScholarPubMed
Rose, P. E. 1980 Improved tables for the evaluation of sphere size distributions including the effect of section thickness. Journal of Microscopy 118, 135–141CrossRefGoogle ScholarPubMed
Schmidt, D. G., Walstra, P. & Buckheim, W. 1973 The size distribution of casein micelles in cow's milk. Netherlands Milk and Dairy Journal 27 128–142Google Scholar
Underwood, E. E. 1970 Quantitative Stereology Reading, MA: Addison-Wesley Publishing CompanyGoogle Scholar
Vreeman, H. J., Van Markwijk, B. W. & Both, P. 1989 The structure of casein micelles between pH 5·5 and 6·7 as determined by light-scattering, electron microscopy and voluminosity experiments. Journal of Dairy Research 56 463–470CrossRefGoogle Scholar