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Heat-induced association-dissociation of casein micelles preceding coagulation

Published online by Cambridge University Press:  01 June 2009

Kais S. Mohammad  and
Patrick F. Fox
Kais S. Mohammad
Affiliation:
Department of Dairy and Food Chemistry, University College, Cork, Irish Republic,
Patrick F. Fox
Affiliation:
Department of Dairy and Food Chemistry, University College, Cork, Irish Republic,
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Summary

Heating milk at 140 °C caused an initial increase in the percentage of total casein sedimented at 10000 g for 1 h and in the relative viscosity, but as heating continued both parameters decreased before increasing again just before the onset of visible coagulation. This suggests that heating milk at high temperatures caused an initial aggregation of casein micelles with a concomitant increase in particle size and weight, followed by dissociation of these aggregates with reaggregation just before coagulation. Chromatography of heated milk on controlled pore glass confirmed the above suggestion. Calcium appeared to play a major role in the initial association of casein micelles which was also influenced by the initial pH and total solids concentration but whey protein had no effect.

Type
Original Articles
Information
Journal of Dairy Research , Volume 54 , Issue 3 , August 1987 , pp. 377 - 387
Copyright
Copyright © Proprietors of Journal of Dairy Research 1987

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References

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