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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
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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

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References

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