Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-17T18:33:13.900Z Has data issue: false hasContentIssue false
  • English
  • Français

Factors affecting the volume of milk delivered by a standard loop in the plate loop method for bacterial count

Published online by Cambridge University Press:  01 June 2009

Joseph S. King  and
Leonard A. Mabbit
Joseph S. King
Affiliation:
*National Institute for Research in Dairying (University of Reading), Shinfield, Reading RG2 9 AT, UK
Leonard A. Mabbit
Affiliation:
*National Institute for Research in Dairying (University of Reading), Shinfield, Reading RG2 9 AT, UK
Get access Rights & Permissions [Opens in a new window]

Summary

Of the various factors influencing the volume transferred by the loop in the automated plate loop technique for enumerating bacteria in milk, the speed of the loop as it emerged from the milk sample was the most important. Increasing this speed from 3 to 6 cm/s resulted in a 23% increase in volume transferred by a standard loop of internal diam. 1·45 mm. The depth of dip was also important, but changes in temperature of the sample from 5 to 20 °C caused no significant change in volume transferred. The results indicate that if the transfer of 1 µl milk is required at speeds commonly used in the automated plate loop technique, the internal diam. of the loop should be reduced from the present standard 1·45 to 1·3 mm.

Type
Original Articles
Information
Journal of Dairy Research , Volume 51 , Issue 2 , May 1984 , pp. 317 - 324
Copyright
Copyright © Proprietors of Journal of Dairy Research 1984

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

American Public Health Association 1972 Standard methods for the examination of dairy products 13th ednWashington DC: American Public Health AssociationGoogle Scholar
Aschaffenbukg, R. 1946 Surface activity and proteins of milk. Journal of Dairy Research 14 316–329CrossRefGoogle Scholar
Brodsky, M. H. & Ciebin, B. W. 1980 Collaborative evaluation of the Plate Loop Technique for determining viable bacterial counts in raw milk. Journal of Food Protection 43 287–291CrossRefGoogle ScholarPubMed
Davis, J. G. 1955 A Dictionary of Dairying, 2nd ednLondon: Leonard HillGoogle Scholar
Grappin, R. & Jeunet, R. 1982 Mechanization of a simplified method for the total plate count of milk. 21st International Dairy Congress, Moscow 1 (2) p. 530Google Scholar
Jasper, D. E. & Dillinger, J. 1966 Variations in volume of milk delivered by a standard 0·01 ml loop. Journal of Milk and Food Technology 29 199–200Google Scholar
Kitchen, B. J. 1981 Review of the progress of Dairy Science: Bovine Mastitis: milk compositional changes and related diagnostic tests. Journal of Dairy Research 48 167–188CrossRefGoogle ScholarPubMed
Malcolm, D. B., Freke, C. D. & Cox, N. R. 1979 Assessment of the bacteriological quality of raw milk in New Zealand. Part 3: Simplified plate count method; the Plate Loop Method and the Autoloop. New Zealand Journal of Dairy Science and Technology 14 A101–A104Google Scholar
Posthumus, G., Klijn, C. J. & Giesen, Th. J. J. 1974 A mechanised loop method for total count of bacteria in refrigerated suppliers′ milk. Netherlands Milk and Dairy Journal 28 79–92Google Scholar
Tatini, S. R., Dabbah, R. & Olson, J. C. 1967 Comparison of Plate Loop and Agar Plate methods of bacteriological examination of manufacturing grade raw milk. Journal of Milk and Food Technology 30 112–115CrossRefGoogle Scholar
Thompson, D. I., Donnelly, C. B. & Black, L. A. 1960 A plate loop method for determining viable counts of raw milk. Journal of Milk and Food Technology 23 167–171Google Scholar
Wright, E. O., Reinbold, G. W., Burmeister, L. & Mellon, J. 1970 Prediction of standard plate count of manufacturing-grade raw milk from the plate loop count. Journal of Milk and Food Technology 33 168–170Google Scholar