Report of the Greater Manchester/Lancashire/PHLS Liaison Group Survey on
the Microbiological Examination of Outer Packaging of Prepacked Fresh
Chicken for Salmonella spp and Campylobacter spp.
K Williamson, G Allen, F J Bolton. PHLS North West FESL – Preston PHL.
Date of Report, March 2000.
Survey Code No. 904015
Introduction
Poultry are an important source of Salmonella and Campylobacter infections in man.
Chicken pieces and whole fresh chicken are often packaged in polystyrene trays prewrapped in clear cellophane or plastic film. More recently some supermarkets have
introduced plastic trays with heat sealed plastic lids. Both types of packaging present
the purchaser with a convenient, attractive product which appears safe and hygienic.
The outer packaging of a variety of prepacked raw chicken including whole chicken,
legs, thighs, wings and breast portions were examined to determine the incidence of
Salmonella and Campylobacter. The survey aimed to determine whether the handling
of pre-packed fresh chicken at retail could be a potential risk to health.
Materials and Method
Sample Collection
This survey was carried out as part of the Greater Manchester FLG/Lancashire
FOG/Preston PHL sampling programme during October – December 1999. Samples
consisted of fresh pre-packed whole chicken or chicken pieces. The samples were
collected from refrigerated supermarket displays by local authority sampling officers.
Information relating to the premises, sample details, condition and type of packaging
and type of container was recorded on a standard PHL food request form.
Sample Examination
A total of 243 chicken samples were submitted from 25/26 authorities in Greater
Manchester and Lancashire as detailed in Appendix 1. The outer packagings of all
243 samples were examined for the presence of Salmonella and Campylobacter using
a swabbing technique and UKAS accredited food methods.
Results
Table 1.
Microbiological results of surface swab samples of retail chicken
outer packaging (n = 243)
Salmonella
Campylobacter
KW/KLM (222000)
Detected (%)
0
14 (5.8)
Page 1 of 3
Not detected (%)
243 (100)
229 (94.2)
Table 2.
Campylobacter results in relation to type of packaging.
Type of packaging
Polystyrene tray/cellophane wrap (n = 222)
Plastic tray/heat sealed plastic lid (n = 21)
NB.
Campylobacter detected (%)
14 (6.4)
0
All 14 Campylobacter detections were obtained from samples with intact
packaging.
Conclusions

Campylobacter were detected from 14/243 (5.8%) of outer packaging. The
incidence is of concern and highlights an important potential mode of
transmission for Campylobacter infections.

Salmonella were not detected from any of the outer packaging.

Food handlers and consumers may be aware that raw poultry is a hazard, but there
is a probable perception that the outer packaging is clean and safe. Failure at this
critical control point may contribute to the risk of acquiring Campylobacter
infection.

Heat sealed plastic trays may be less of a problem.
Future work

Further surveys relating to potential sources of Campylobacter in retail outlets.

Future sampling points need to be identified i.e. supermarket conveyor belts,
shopping trolleys/baskets, shelving.

Further surveys relating to presence of Campylobacter on frozen poultry
packaging, and the presence of Campylobacter and other pathogens on other types
of meat packaging need to be investigated.
KW/KLM (222000)
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APPENDIX 1
SURVEY NUMBER 904015
OUTER PACKAGING OF RAW CHICKEN
PRESTON PHL
Tested October 1999 to December 1999.
A total of 243 samples were tested from 25 authorities.
Authority
Barrow
Blackpool
Burnley
Chorley
Fylde
Hyndburn
Lancaster
Pendle
Preston
Ribble Valley
Rossendale
South Lakes
South Ribble
West Lancs
Wyre
Bolton
Bury
Manchester
Oldham
Rochdale
Salford
Stockport
Tameside
Trafford
Wigan
TOTAL
KW/KLM (222000)
Number of
samples
10
12
12
12
12
7
12
4
11
6
10
12
8
11
8
8
12
12
8
8
4
12
12
8
12
243
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