Assessment of the Microbiological Quality of Meat Pies from Retail Sale in England 2013.
Outbreaks of foodborne illness caused by Bacillus cereus and Listeria monocytogenes in England associated with meat pie consumption were detected in 2012. To obtain baseline data for pies unrelated to outbreaks, 862 samples of ready-to-eat meat pies were collected at retail or from catering facilities in England in 2013 and examined to enumerate food-poisoning bacteria and indicator organisms using Organization for Standardization (ISO) methods for Listeria spp. including L. monocytogenes (ISO 11290), Clostridium perfringens (ISO 21528), coagulase-positive staphylococci including Staphylococcus aureus (ISO 6888), Bacillus spp. including B. cereus (ISO 1737), Escherichia coli (ISO 16649), Enterobacteriaceae (ISO 21528), and aerobic colony counts (ACCs; ISO 4833). Microbiological quality was satisfactory in 94% of samples, borderline in 5%, and unsatisfactory in 1%. The proportion of pies from markets that were borderline or unsatisfactory significantly increased, and the proportion of borderline or unsatisfactory pies from supermarkets significantly decreased. Among the refrigerated (0 to 15°C) pies, microbiological quality significantly decreased in pies stored at >8°C and further significantly decreased at in pies stored at ambient temperature (>15 to 25°C). Samples collected at 25 to 40°C had the highest proportion of borderline or unsatisfactory results, but results improved in pies stored at >40°C. The most common cause for borderline or unsatisfactory results was elevated ACCs (5% of all samples). Within the individual microbiological parameters, borderline or unsatisfactory results resulted from elevated Enterobacteriaceae or Bacillus levels (10 samples for each), C. perfringens levels (2 samples), and S. aureus or E. coli levels (1 sample each). L. monocytogenes was recovered from one pie at <10 CFU/g. A literature review revealed a range of microbiological hazards responsible for food poisoning and meat pie consumption, and surveillance data from 1992 to 2012 from England indicated that C. perfringens was the most commonly reported cause of outbreaks of foodborne illness.
Food, Water, and Environmental Microbiology Services, Public Health England, London NW9 5EQ, UK; Institute of Infection and Global Health, University of Liverpool, Liverpool L69 3GL, UK.
Jim
J
McLauchlin
Food, Water, and Environmental Microbiology Laboratory York, National Agri-Food Innovation Campus, Public Health England, York YO41 1LZ, UK.
Heather
H
Aird
Statistics Modelling and Economics Department, Public Health England, London NW9 5EQ, UK.
Andre
A
Charlett
Food, Water, and Environmental Microbiology Laboratory London, Public Health England, London, NW9 5EQ, UK.
Nicola
N
Elviss
Food, Water, and Environmental Microbiology Laboratory Preston, Royal Preston Hospital, Public Health England, Preston PR2 9HT, UK.
Andrew
A
Fox
Food, Water, and Environmental Microbiology Laboratory Birmingham, Good Hope Hospital, Public Health England, Sutton, Coldfield B75 7RR, UK.
Moira
M
Kaye
Food, Water, and Environmental Microbiology Laboratory Porton, Public Health England, Porton Down, Salisbury SP4 0JG, UK.
Caroline
C
Willis
D015169:Colony Count, Microbial; D004739:England; D004926:Escherichia coli; D005516:Food Microbiology; D008089:Listeria monocytogenes; D008460:Meat / Q000382:microbiology; D013211:Staphylococcus aureus