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Heat-induced changes in sodium Caseinate

Published online by Cambridge University Press:  01 June 2009

Mingruo Guo,
Patrick F. Fox,
Albert Flynn and
Kais S. Mahammad
Mingruo Guo
Affiliation:
Department of Food Chemistry, University College, Cork, Ireland
Patrick F. Fox
Affiliation:
Department of Food Chemistry, University College, Cork, Ireland
Albert Flynn
Affiliation:
Department of Nutrition, University College, Cork, Ireland
Kais S. Mahammad
Affiliation:
Department of Food Chemistry, University College, Cork, Ireland
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Summary

Chemical and physical changes that occur in Na caseinate (at 1 or 2% in water, pH 7·0) on heating in the range 120–150 °C were investigated by polyacrylamide gel electrophoresis, ion-exchange and gel-permeation chromatography, light scattering, u.v. spectroscopy, amino acid analysis, and the formation of pH 4·6 and 12% TCA-soluble N and 12% TCA-soluble P. The electropherograms of heated samples were smeared and indistinct suggesting intermolecular aggregation which was not reversed by 6 M-urea or SDS and indicating covalent bond formation; αs2-casein was especially sensitive. Aggregation was confirmed by ion-exchange chromatography and light scattering. Fragmentation of the caseins also occurred on heating, as indicated by the formation of pH 4·6 and 12% TCA-soluble N and by gel filtration. Formation of soluble N and dephosphorylation followed first-order kinetics. Concentrations of available lysine and available methionine were reduced by 10–15% on heating at 140 °C for 30min; chemical assays for arginine and tryptophan indicated increases, suggesting interference. Ultraviolet spectroscopy indicated a slight apparent increase in aromatic residues after heating at 140 °C for up to 60 min.

Information

Type
Original Articles
Information
Journal of Dairy Research , Volume 56 , Issue 3: Special Issue: Proceedings of the Hannah Research Institute Casein Conference , May 1989, pp. 503 - 512
Copyright
Copyright © Proprietors of Journal of Dairy Research 1989

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References

REFERENCES

Andrews, A. T. 1983 Proteinases in normal bovine milk and their action on caseins. Journal of Dairy Research 50 45–50Google Scholar
A.O.A.C. 1970 Official Methods of the Association of Official Analytical Chemists, 11th Edition, p. 861. Washington, D.C.: A.O.A.C.Google Scholar
Belec, J. & Jenness, R. 1962 a Dephosphorylation of casein by heat treatment. I. In caseinate solutions. Journal of Dairy Science 45 12–19Google Scholar
Belec, J. & Jenness, R. 1962 b Dephosphorylation of casein by heat treatment. II. In skim milks. Journal of Dairy Science 45 20–26CrossRefGoogle Scholar
Burton, H. 1984 Reviews in the progress of Dairy Science: the bacteriological, chemical, biochemical and physical changes that occur in milk at temperatures of 100–150 °C. Journal of Dairy Research. 51 341–363Google Scholar
Carpenter, K. J. 1960 The estimation of available lysine in animal protein foods. Biochemical Journal 77 604–610CrossRefGoogle ScholarPubMed
Cherry, J. P. 1982 Food Protein Deterioration. ACS Symposium Series 206. Washington, D.C.: American Chemical SocietyGoogle Scholar
Creamer, L. K. & Richardson, T. 1984 Anomalous behaviour of bovine αs1- and β-caseins on gel electrophoresis in SDS buffers. Archives of Biochemistry and Biophysics 234 476–486Google Scholar
Feeney, R. E. & Whitaker, J. R. 1977 Food Proteins. Improvement Through Chemical and Enzymatic Modification. Advances in Chemistry Series 160. Washington, D.C.: American Chemical SocietyGoogle Scholar
Feeney, R. E. & Whitaker, J. R. 1988 In Advances in Cereal Science and Technology, vol. ix pp. 21–45; (Ed. Pomeranz, Y.). St Paul: American Association of Cereal ChemistryGoogle Scholar
Fox, P. F. 1981 Heat stability of milk: significance of heat-induced acid formation in coagulation. Irish Journal of Food. Science and. Technology 51–11Google Scholar
Fox, P. F. 1982 In Developments inDairy Chemistry. I. Proteins, pp. 189–228. (Ed. Fox, P. F.). London: Applied Science PublishersGoogle Scholar
Fox, P. F. & Morrissey, P. A. 1977 Reviews in the progress of Dairy Science: the heat stability of milk. Journal of Dairy Research 44 627–646Google Scholar
Friedman, M. (ed.) 1977 Protein Crosslinking: Nutritional and Medical Consequences. New York: Plenum PressGoogle Scholar
Howat, G. R. & Wright, N. C. 1934 The heat-coagulation of caseinogen. I. The role of phosphorus cleavage. Biochemical Journal 28 1336–1345Google Scholar
Howat, G. R. & Wright, N. C. 1936 The heat coagulation of milk. II. The rate of phosphorus cleavage. Biochemical Journal 30 1413–1415CrossRefGoogle Scholar
IDF 1964 Determination of the Casein Content of Milk. IDF Standard 29. Brussels: International Dairy FederationGoogle Scholar
IDF 1988 Heat-induced Changes in Milk. Document No. (in Press). Brussels: International Dairy FederationGoogle Scholar
Laemmli, U. K. 1970 Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature 227 680–685Google Scholar
McCarthy, T. E. & Sullivan, M. X. 1941 A new and highly specific colorimetrie test for methionine. Journal of Biological Chemistry 141 871–876Google Scholar
Muir, D. D. 1985 Heat stability of milk and concentrated milk. International Journal of Biochemistry 17 291–299Google Scholar
Pieniazek, D., Rakouska, M., Szkilladziowa, W. & Grabatek, Z. 1975 Estimation of available methionine and cysteine in proteins of food products by in vivo and in vitro methods. British Journal of Nutrition 3 175–190Google Scholar
Singh, H. & Fox, P. F. 1985 Heat stability of milk: pH dependent dissociation of micellar k−casein on heating milk at ultra high temperatures. Journal of Dairy Research 52 529–539Google Scholar
Spies, J. R. & Chambers, D. C. 1949 Chemical determination of tryptophan in proteins. Analytical Chemistry 21 1249–1266Google Scholar
Tomlinson, G. & Viswanatha, T. 1974 Determination of arginine content of proteins by the Sakaguchi procedure. Analytical Biochemistry 60, 15–24Google Scholar
Whitney, R. Mcl., Brunner, J. R., Ebner, K. E., Farrell, H. M. Jr, Josephson, R. V., Morr, C. V. & Swaigoood, H. E. 1976 Nomenclature of cow's milk: Fourth revision. Journal of Dairy Science 59 795–815Google Scholar