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Some factors involved in milk lipase activation by agitation

Published online by Cambridge University Press:  01 June 2009

H. C. Deeth
Affiliation:
Otto Madsen Dairy Research Laboratory, Hamilton 4007, Brisbane, Australia
C. H. Fitz-Gerald
Affiliation:
Otto Madsen Dairy Research Laboratory, Hamilton 4007, Brisbane, Australia

Summary

Several factors which influence the shape of activation curves relating the degree of agitation-induced lipolysis in raw milk to the temperature of agitation were investigated. Curves of the type previously reported (Fitz-Gerald, 1974) containing a maximum at 12–15 °C resulted from low speed agitation with incorporation of air, with fresh (< 12-h old) milk, with milk of fat content ≥ 3·0 % approx. and by low temperature incubation of activated milks. Activation curves containing no distinct maximum at 12–15 °C were obtained from high speed agitation and homogenization, with milks of low fat contents and with aged (≥ 24-h old) milk. Agitation at low temperatures resulted in a maximum degree of activation in fresh milk after 2–4 h cold storage.

During agitation of raw milk redistribution of lipase activity between the cream and skim-milk phases occurred. The extent of redistribution depended on the time and temperature of agitation. Cream prepared from milk agitated at low temperatures contained lipase activity several times greater than cream from unactivated milk. The practical significance of this effect is discussed.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1977

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References

REFERENCES

Claypool, L. L. (1965). Thesis. University of Minnesota.Google Scholar
Deeth, H. C. & Fitz-Gerald, C. H. (1975). Annual Bulletin, International Dairy Federation (Doc. 86), 24.Google Scholar
Deeth, H. C., Fitz-Gerald, C. H. & Wood, A. F. (1975). Australian Journal of Dairy Technology 30, 109.Google Scholar
Downey, W. K. (1974). 19th International Dairy Congress, New Delhi 1E, 351.Google Scholar
Dunkley, W. L. & Smith, L. M. (1951). Journal of Dairy Science 34, 940.CrossRefGoogle Scholar
Fitz-Gerald, C. H. (1974). Australian Journal of Dairy Technology 29, 28.Google Scholar
Frankel, E. N. & Tarassuk, N. P. (1959). Journal of Dairy Science 42, 409.CrossRefGoogle Scholar
Henningson, R. W. & Adams, J. B. (1967). Journal of Dairy Science 50, 961.Google Scholar
Hlynka, I., Hood, E. G. & Gibson, C. A. (1944). Canadian Dairy and Ice Cream Journal 23 (3), 26.Google Scholar
I.D.F. Lipolysis Group (1974). Annual Bulletin, International Dairy Federation. (Doc.82).Google Scholar
Kelley, L. A. & Dunkley, W. L. (1954). Journal of Milk and Food Technology 17, 306.CrossRefGoogle Scholar
Kitchen, B. J. & Aston, J. W. (1970). Australian Journal of Dairy Technology 25, 10.Google Scholar
Krukovsky, V. N. & Sharp, P. F. (1938). Journal of Dairy Science 21, 671.CrossRefGoogle Scholar
Mulder, H. & Walstra, P. (1974). The milk fat globule: emulsion science as applied to milk products and comparable foods. Farnham Royal, Bucks: Commonwealth Agricultural Bureaux.Google Scholar
Reiter, B., Dellaglio, F. & Sharpe, M. E. (1970). National Institute for Research in Dairying, Report 1969–1970, 151.Google Scholar
Rout, T. P. (1971). Proceedings, Australian Biochemical Society 4, 73.Google Scholar
Tarassuk, N. P. & Frankel, E. N. (1955). Journal of Dairy Science 38, 438.CrossRefGoogle Scholar
Tarassuk, N. P. & Frankel, E. N. (1957). Journal of Dairy Science 40, 418.CrossRefGoogle Scholar
Tarassuk, N. P. & Yaguchi, M. (1958). Journal of Dairy Science 41, 708.Google Scholar