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A quantitative study of changes in dried skim-milk and lactose-casein in the ‘dry’ state during storage

Published online by Cambridge University Press:  01 June 2009

E. L. Richards
E. L. Richards
Affiliation:
Chemistry and Biochemistry Department, Massey University College, Palmerston North, New Zealand
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Summary

Changes in dried skim-milk and in lactose-casein in the ‘dry’ state during storage at 45 °C and 75% r.h. have been studied by the determination of free amino-N, ε-amino groups of lysine, galactose, lactulose, tagatose and 1-amino-1-deoxy-2-ketoses, and by the measurement of changes in colour, solubility and ferricyanide reducing power.

In both systems there is initially a close relationship between the formation of 1-amino-1-deoxy-2-ketoses and the decrease in free amino-N. This conforms with an Amadori rearrangement of an initially formed lactose-protein complex. Change in colour is rapid only after there has been a rapid formation of 1-amino-1-deoxy-2-ketoses and a corresponding decrease in free amino-N. This conforms with browning being due to a breakdown of the Amadori rearranged complex.

It is postulated that galactose and tagatose may be formed by both the basecatalysed degradation of lactose and also by breakdown of the Amadori rearranged lactose-protein complex. Lactulose is postulated to be formed only by base-catalysed degradation of lactose.

Type
Original Articles
Information
Journal of Dairy Research , Volume 30 , Issue 2 , June 1963 , pp. 223 - 234
Copyright
Copyright © Proprietors of Journal of Dairy Research 1963

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References

REFERENCES

Adachi, S. (1956). Nature, Lond., 177, 936.Google Scholar
Adachi, S. (1957). Chem. & Ind. p. 956.Google Scholar
Adachi, S. & Patton, S. (1961). J. Dairy Sci. 44, 1375.Google Scholar
American Dry Milk Institute Inc. (1954). Standard Methods of Analysis Bull., no. 911.Google Scholar
Baliga, B. P., Bayliss, M. E. & Lyman, C. M. (1959). Arch. Biochem. Biophys. 84, 1.Google Scholar
Bath, I. H. (1958). Analyst, 83, 451.Google Scholar
Bell, D. J. (1955). Modern Methods of Plant Analysis, vol. 2, p. 21. Berlin: Springer-Verlag.Google Scholar
Carpenter, K. J. (1960). Biochem. J. 77, 604.CrossRefGoogle Scholar
Choi, R. P., Koncus, A. F., Cherrey, G. & Remaley, R. J. (1953). J. Milk Fd Tech. 16, 241.Google Scholar
Corbett, W. M. & Kenner, J. (1953). J. Chem. Soc. p. 2245.Google Scholar
Gottschalk, A. (1952). Biochem. J. 52, 455.Google Scholar
Henry, K. M., Kon, S. K., Lea, C. H. & White, J. C. (1948). J. Dairy Res. 15, 292.Google Scholar
Hodge, J. E. (1953). J. agric. Fd Chem. 1, 928.Google Scholar
Hodge, J. E. (1955). Advanc. Carbohydr. Chem. 10, 169.Google Scholar
Keeney, M. & Bassette, R. (1959). J. Dairy Sci. 42, 945.Google Scholar
Lea, C. H. (1948). J. Dairy Res. 15, 364.Google Scholar
Lea, C. H. & Hannan, R. S. (1949). Biochim. biophys. Acta, 3, 313.Google Scholar
Lea, C. H. & Hannan, R. S. (1950 a). Biochim. biophys. Acta, 4, 518.Google Scholar
Lea, C. H. & Hannan, R. S. (1950 b). Biochim. biophys. Acta, 5, 433.Google Scholar
Montgomery, E. M. & Hudson, C. S. (1930). J. Amer. chem. Soc. 52, 2101.Google Scholar
Nelson, N. (1944). J. biol. Chem. 153, 375.CrossRefGoogle Scholar
Porter, R. R. & Sanger, F. (1948). Biochem. J. 42, 287.Google Scholar
Richards, E. L. & Chandrasekhara, M. R. (1960). J. Dairy Res. 27, 59.Google Scholar