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The microbiology of selected retail food products with an evaluation of viable counting methods

Published online by Cambridge University Press:  19 October 2009

M. H. Greenwood
Affiliation:
Public Health Laboratory, Poole General Hospital, Poole BH15 2JB
E. F. C. Coetzee
Affiliation:
Public Health Laboratory, Glyde Path Road, Dorchester DT1 1XD
B. M. Ford
Affiliation:
Public Health Laboratory, Poole General Hospital, Poole BH15 2JB
P. Gill
Affiliation:
Public Health Laboratory, Glyde Path Road, Dorchester DT1 1XD
W. L. Hooper
Affiliation:
Public Health Laboratory, Poole General Hospital, Poole BH15 2JB
S. C. W. Matthews
Affiliation:
Public Health Laboratory, Odstock Hospital, Salisbury SP2 8BJ
S. Patrick
Affiliation:
Public Health Laboratory, Odstock Hospital, Salisbury SP2 8BJ
J. V. S. Pether
Affiliation:
Public Health Laboratory, Taunton and Somerset Hospital, Musgrove Park Branch, Taunton TA1 5DB
R. J. D. Scott
Affiliation:
Public Health Laboratory, Taunton and Somerset Hospital, Musgrove Park Branch, Taunton TA1 5DB
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Summary

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In an inter-laboratory survey, the pour plate, surface spread, agar droplet and spiral plate methods were used in parallel with the surface drop method for enumeration of micro-organisms in foods. Good agreement was obtained between all surface methods of enumeration, but there was poor agreement between molten agar methods and the surface drop method.

A total of 1143 samples of food that were ready for consumption at the point of retail sale were examined. Eight types of food products were chosen: meat pasties, sausage rolls, real-cream slices, synthetic-cream slices, mayonnaise-based coleslaws, faggots, patés and continental sausages. The results of this survey suggest that the upper limit for an acceptable viable count should vary according to the food product. Salmonellae were not isolated on any occasion. Potentially harmful organisms were not isolated at levels expected to constitute a public health hazard.

Information concerning the nature of the product, the total viable count, the presence or absence of pathogenic, toxigenic or indicator organisms, the spectrum of the bacterial flora and the relative predominance of each organism must all be considered when assessing the microbiological acceptability of retail ‘ready to eat’ products.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1984

References

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