An assessment of the microbiological quality of lightly cooked food (including sous-vide) at the point of consumption in England

Epidemiol Infect. 2017 May;145(7):1500-1509. doi: 10.1017/S0950268817000048. Epub 2017 Feb 27.

Abstract

This observational study aims to investigate the microbiological quality of commercially prepared lightly cooked foods with a major component of food of animal origin and collected as would be served to a consumer. A total of 356 samples were collected from catering (92%), retail (7%) or producers (1%) and all were independent of known incidents of foodborne illness. Using standard methods, all samples were tested for: the presence of Campylobacter spp. and Salmonella spp. and enumerated for levels of, Bacillus spp. including B. cereus, Clostridium perfringens, Listeria spp. including L. monocytogenes, Staphylococcus aureus, Escherichia coli, Enterobacteriacea and aerobic colony count (ACC). Results were interpreted as unsatisfactory, borderline or satisfactory according to the Health Protection Agency guidelines for assessing the microbiological safety of ready-to-eat foods placed on the market. Amongst all samples, 70% were classified as satisfactory, 18% were borderline and 12% were of unsatisfactory microbiological quality. Amongst the unsatisfactory samples, six (2%) were potentially injurious to health due to the presence of: Salmonella spp. (one duck breast); Campylobacter spp. (two duck breast and one chicken liver pâté); L. monocytogenes at 4·3 × 103 cfu (colony-forming units)/g (one duck confit with foie gras ballotin) and C. perfringens at 2·5 × 105 cfu/g (one chicken liver pâté). The remaining unsatisfactory samples were due to high levels of indicator E. coli, Enterobacteriaceae or ACC.

Keywords: Catering; food safety; lightly cooked food; liver; microbiological quality; poultry products; sous-vide.

MeSH terms

  • Bacteria / isolation & purification*
  • Cooking*
  • England
  • Food Microbiology* / statistics & numerical data
  • Humans
  • Meat / microbiology*
  • Meat Products / microbiology