Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-11-30T03:13:21.037Z Has data issue: false hasContentIssue false
  • English
  • Français

Thermal denaturation of α-lactalbumin and β-lactoglobulin in cheese whey: effect of total solids concentration and pH

Published online by Cambridge University Press:  01 June 2009

Robyn M. Hillier ,
Richard L. J. Lyster  and
Gordon C. Cheeseman
Robyn M. Hillier
Affiliation:
National Institute for Research in Dairying, Shinfield, Beading, RG2 9AT
Richard L. J. Lyster
Affiliation:
National Institute for Research in Dairying, Shinfield, Beading, RG2 9AT
Gordon C. Cheeseman
Affiliation:
National Institute for Research in Dairying, Shinfield, Beading, RG2 9AT
Get access Rights & Permissions [Opens in a new window]

Summary

Measurements of residual native protein remaining after heat treatment of cheese whey have been made using quantitative polyacrylamide gel electrophoresis. The results have been expressed in terms of kinetic constants. The effect of concentration was investigated up to 3 times the normal total solids content, dialysis treatments were used to study the effect of non-protein constituents, and the effect of pH was studied at pH 4, 6 and 9. The results indicated that increased total solids (TS) concentration slowed the denaturation of β-lactoglobulin A and B (β-lg A, β-lg B) but hastened the denaturation of α-lactalbumin (α-la). However, increased lactose concentration slowed the denaturation of both α-la and β-lg, perhaps by preventing formation of heat-induced complexes. Increased Ca concentration, up to 0.4 mg/ml, tended to slow the denaturation of both proteins, but further increase in Ca up to 0.9 mg/;ml produced little effect. The rate of denaturation of both α-la and β-lg was slower at pH 4 than at pH 6 or 9, and was probably slowest at the isoelectric point. However, not all the changes associated with pH could be explained in terms of net molecular electrostatic charge. The genetic variants of ′β-lg showed different heat stabilities – below 90 °C β-lgA was more stable than β-lgB, but above 90 °C the situation was reversed at all TS concentrations, and pH 6. However, at pH 4 and 9, °-lgA was less stable than °-lgB over the entire temperature range at normal concentration.

Type
Original Articles
Information
Journal of Dairy Research , Volume 46 , Issue 1 , January 1979 , pp. 103 - 111
Copyright
Copyright © Proprietors of Journal of Dairy Research 1979

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

Aschaffenburg, R. & Drewry, J. (1957). Biochemical Journal 65, 273.CrossRefGoogle Scholar
British Standards Institution (1963). B.S. No. 1741.Google Scholar
D'souza, S. V., Lund, D. B. & Amundson, C. H. (1973). Journal of Food Science 38, 519.Google Scholar
Dupont, M. (1965). Biochimica et Biophysica Acta 94, 573.CrossRefGoogle Scholar
Gordon, W. G., Basch, J. J. & Kalan, E. B. (1961). Journal of Biological Chemistry 236, 2908.CrossRefGoogle Scholar
Guy, E. J., Vettel, H. E. & Pallansch, M. J. (1967). Journal of Dairy Science 50, 828.CrossRefGoogle Scholar
Hillier, R. M. (1976). Journal of Dairy Research 43, 259.Google Scholar
Hillier, R. M. & Lyster, R. L. J. (1979). Journal of Dairy Research 46, 95.CrossRefGoogle Scholar
Hulett, J. R. (1964). Quarterly Reviews, Chemical Society 18, 227.CrossRefGoogle Scholar
Jones, S. B., Kalan, E. B., Jones, T. C. & Hazel, J. F. (1972). Journal of Agricultural and Food Chemistry 20, 229.Google Scholar
Kalan, E. B., Gordon, W. G., Basch, J. J. & Townend, R. (1962). Archives of Biochemistry and Biophysics 96, 376.Google Scholar
Kronman, M. J., Andreotti, R. & Vitols, R. (1964). Biochemistry 3, 1152.Google Scholar
Marshall, P. G., Dunkley, W. L. & Lowe, E. (1968). Food Technology 22, 915.Google Scholar
McDonough, F. E. & Mattingly, W. A. (1970). Food Technology 24, 194.Google Scholar
McDonough, F. E., Mattingly, W. A. & Vestal, J. H. (1971). Journal of Dairy Science 54, 1406.CrossRefGoogle Scholar
McKenzie, H. A. (1971). In Milk Proteins: Chemistry and Molecular Biology, vol. 2, p. 257. (Ed. McKenzie, H. A..) New York, USA: Academic Press.CrossRefGoogle Scholar
Morr, C. V., Nielsen, M. A. & Coulter, S. T. (1967). Journal of Dairy Science 50, 305.CrossRefGoogle Scholar
Nielsen, M. A., Coulter, S. T., Morr, C. V. & Rosenau, J. R. (1973). Journal of Dairy Science 56, 76.CrossRefGoogle Scholar
Palmer, D. E. (1977). Process Biochemistry 12 (5), 24.Google Scholar
Richert, S. H. (1975). Journal of Dairy Science 58, 985.Google Scholar
Robbins, F. M., Andreotti, R. E.Holmes, L. G. & Kronman, M. J. (1967). Biochimica et Biophysica Acta 133, 33.CrossRefGoogle Scholar
Tanford, C. (1961). Physical Chemistry of Macromolecules. New York, USA: John Wiley & Sons, Inc.Google Scholar
Yamauchi, K. (1961). Japanese Journal of Zoolechnical Science 31, 304.Google Scholar
Zadow, J. G. & Hill, R. D. (1975). Journal of Dairy Research 42, 267.CrossRefGoogle Scholar
Zittle, C. A. (1956). Archives of Biochemistry and Biophysics 64, 144.CrossRefGoogle Scholar