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Changes in milk on heating: viscosity measurements

Published online by Cambridge University Press:  01 June 2009

Theo J. M. Jeurnink
Affiliation:
Netherlands Institute for Dairy Research(NIZO), PO Box 20, 6710 BA Ede, The Netherlands
Kees G. De Kruif
Affiliation:
Netherlands Institute for Dairy Research(NIZO), PO Box 20, 6710 BA Ede, The Netherlands

Summary

Skim milk was heated at 85 °C for different holding times. As a result of such heating, whey proteins, in particular β-lactoglobulin, denatured and associated with casein micelles. This led to an increase in size of the casein micelles but also to a different interaction between them. Both these changes could be described by using a quantitative model which was developed for the viscosity of so-called adhesive hard spheres. We applied the model successfully to skim milk and were able to describe on a quantitative basis the changes due to the heat treatment of milk. It was shown that after heating the casein micelles became larger and acquired a mutual attraction. The unfolding of the whey proteins and their subsequent association with the casein micelles appeared to be responsible for these changes. How this reaction influences the fouling of heat exchangers is discussed.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1993

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References

REFERENCES

Arnebrant, T., Barton, K. & Nylander, T. 1987 Adsorption of α-lactalbumin and β-lactoglobulin on metal surfaces versus temperature. Journal of Colloid and Interface Science 119 383390CrossRefGoogle Scholar
Batchelor, G. K. 1977 The effect of Brownian motion on the bulk stress in a suspension of spherical particles. Journal of Fluid Mechanics 83 97117CrossRefGoogle Scholar
Baxter, R. J. 1968 Pereus-Yevick equation for hard spheres with surface adhesion. Journal of Chemical Physics 49 27702774CrossRefGoogle Scholar
Burton, H. 1968 Reviews of the Progress of Dairy Science. Section G. Deposits from whole milk in heat treatment plant–a review and discussion. Journal of Dairy Research 35 317330CrossRefGoogle Scholar
Cichocki, B. & Felderhof, B. U. 1988 Long-time self-diffusion coefficient and zero-frequency viscosity of dilute suspensions of spherical Brownian particles. Journal of Chemical Physics 89 37053709CrossRefGoogle Scholar
Dannenberg, F. & Kessler, H. G. 1988 Application of reaction kinetics to the denaturation of whey proteins in heated milk. Milchwissenschaft 43 37Google Scholar
De Kruif, C. G., Van Iersel, E. M. F. & Vrij, A. 1985 Hard sphere colloidal dispersions: viscosity as a function of shear rate and volume fraction. Journal of Chemical Physics 83 47174725CrossRefGoogle Scholar
Eilers, H. 1941 [The viscosity of emulsions of high-viscous materials as function of the concentration.] Kolloid-Zeitschrift 97 313321CrossRefGoogle Scholar
Griffin, M. C. A., Price, J. C. & Griffin, W. G. 1989 Variation of the viscosity of a concentrated, sterically stabilized, colloid: effect of ethanol on casein micelles of bovine milk. Journal of Colloid and Interface Science 128 223229CrossRefGoogle Scholar
Hiddink, J., Lalande, M., Maas, A. J. R. & Streuper, A. R. 1986 Heat treatment of whipping cream. I. Fouling of the pasteurization equipment. Milchwissenschaft 41 542546Google Scholar
Jeurnink, Th. J. M. 1991 Effect of proteolysis in milk on fouling in heat exchangers. Netherlands Milk and Dairy Journal 45 2332Google Scholar
Jeurnink, Th. J. M. 1992 Changes in milk on mild heating. Turbidity measurements. Netherlands Milk and Dairy Journal 46 183196Google Scholar
Jeurnink, Th. J. M., Brinkman, D. W. & Stemerdink, A. D. 1989 Distribution and composition of deposit in heat exchangers. In Proceedings of the Third International Conference on Fouling and Cleaning in Food Processing, pp. 25–36 (Eds H. G. Kessler and D. B. Lund). Prien, Augsburg: WalchGoogle Scholar
Langley, K. R. & Temple, D. M. 1985 Viscosity of heated skim milk. Journal of Dairy Research 52 223227CrossRefGoogle Scholar
Maubois, J. L., Pierre, A., Fauquant, J. & Piot, M. 1987 Industrial fractionation of main whey proteins. International Dairy Federation Bulletin no. 212 154159Google Scholar
Mohammad, K. S. & Fox, P. F. 1987 Heat-induced association-dissociation of casein micelles preceding coagulation. Journal of Dairy Research 54 377387CrossRefGoogle Scholar
Morr, C. V. 1969 Protein aggregation in conventional and ultra high-temperature heated skimmilk. Journal of Dairy Science 52 11741180CrossRefGoogle Scholar
Nederlands Normalisatie-Instituut 1984 Delft: NNI (NEN 3198 2nd edn)Google Scholar
Pouliot, Y., Boulet, M. & Paquin, P. 1989 Observations on the heat-induced salt balance changes in milk I. Effect of heating time between 4 and 90 °C. Journal of Dairy Research 56 185192CrossRefGoogle Scholar
Russel, W. B. 1984 The Huggins coefficient as a means for characterizing suspended partieles. Journal of the Chemical Society, Faraday Transactions 2 80 3141Google Scholar
Singh, H. & Fox, P. F. 1988 Heat-induced changes in casein. International Dairy Federation Bulletin no. 238 2430Google Scholar
Smits, P. & Van Brouwershaven, J. H. 1980 Heat-induced association of β-lactoglobulin and casein micelles. Journal of Dairy Research 47 313325CrossRefGoogle ScholarPubMed
Snoeren, T. H. M., Damman, A. J. & Klok, H. J. 1982 The viscosity of skim-milk concentrates. Netherlands Milk and Dairy Journal 36 305316Google Scholar
Van Boekel, M. A. J. S., Nieuwenhuijse, J. A. & Walstra, P. 1989 The heat coagulation of milk. 2. Kinetic studies. Netherlands Milk and Dairy Journal 43 129146Google Scholar
Van Der Werff, J. C. & De Kruif, C. G. 1989 Hard-sphere colloidal dispersions: the scaling of rheological properties with particles size, volume fraction, and shear rate. Journal of Rheology 33 421454CrossRefGoogle Scholar
Van Dijk, H. J. M. 1990 The properties of casein micelles. 3. Changes in the state of the micellar calcium phosphate and their effects on other changes in the casein micelles. Netherlands Milk and Dairy Journal 44 125141Google Scholar
Walstra, P. & Jenness, K. 1984 Dairy Chemistry and Physics. New York: WileyGoogle Scholar
Woutersen, A. T. J. M. & De Kruif, C. G. 1991 The rheology of adhesive hard sphere dispersions. Journal of Chemical Physics 94 57395750CrossRefGoogle Scholar