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Factors affecting the concentration of vitamins in milk: III. Effect of season and solar radiation on the vitamin D potency of butter

Published online by Cambridge University Press:  01 June 2009

Kathleen M. Henry
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading RG2 9AT
Zena D. Hosking
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading RG2 9AT
S. Y. Thompson
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading RG2 9AT
Joyce Toothill
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading RG2 9AT
J. D. Edwards-Webb
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading RG2 9AT
L. P. Smith
Affiliation:
Meteorological Office, Bracknell, Berks

Summary

Between August and May-the butter-making season in New Zealand-the average vitamin Dcontent of the butterfat varied between 10 and 64 i.u./100g and during the corresponding months in Great Britain (February-November) the values were between 15 and 39 i.u./100g. At the beginning and end of the season the values in both countries were similarly low but in mid-season New Zealand values were up to twice those for Great Britain. Within each country the vitamin D values were highly correlated with hours of sunshine and, for both countries, with total radiation, which includes the diffuse radiation in ‘skyshine’ and also allows for variation in sunshine intensity. The higher content of vitamin D in New Zealand butter in mid-season was attributed to a higher level of total radiation.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1971

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References

REFERENCES

Abrams, J. T. (1952). Vet. Rec. 64, 151.Google Scholar
Bechtel, H. E. & Hoppert, C. A. (1936). J. Nutr. 11, 537.Google Scholar
Campion, J. E., Henry, K. M., Kon, S. K. & Mackintosh, J. (1937). Biochem. J. 31, 81.Google Scholar
Finney, D. J. (1964). Statistical Method in Biological Assay, 2nd edn.London: Charles Griffin.Google Scholar
Hartman, A. M. & Dryden, L. P. (1965). Vitamins in Milk and Milk Products. Champaign, Illinois: American Dairy Science Association.Google Scholar
Henry, K. M. & Kon, S. K. (1937). Biochem. J. 31, 2199.Google Scholar
Henry, K. M. & Kon, S. K. (1942). Biochem. J. 36, 456.CrossRefGoogle Scholar
Henry, K. M. & Kon, S. K. (1954). J. Dairy Res. 21, 81.Google Scholar
Henry, K. M., Kon, S. K., Thompson, S. Y., McCallum, J. W. & Stewart, J. (1958). Br. J. Nutr. 12, 462.CrossRefGoogle Scholar
Henry, K. M. & Thompson, S. Y. (1954). Milchwissenschaft 9, 14.Google Scholar
Luckiesh, M. (1946). Applications of Germicidal, Erythemal and Infrared Energy. New York: Van Nostrand.Google Scholar
Rosenheim, O. & Webster, T. A. (1927). Biochem. J. 21, 389.Google Scholar
Thompson, S. Y., Henry, K. M. & Kon, S. K. (1964). J. Dairy Res. 31, 1.CrossRefGoogle Scholar
Wallis, G. C. (1938). J. Dairy Sci. 21, 315.CrossRefGoogle Scholar
Who Expert Committee on Biological Standardization (1950). Tech. Rep. Ser. Wld Hlth Org. no. 3. p. 7.Google Scholar
Windaus, A., LettrÉ, H. & Schenck, Fr. (1935). Justus Liebigs Annln Chem. 520, 98.CrossRefGoogle Scholar