Consumer Food Safety Knowledge, Microbiology and Refrigeration Temperatures in Domestic Kitchens

Date: 2005

Foodborne illnesses impose a substantial economic and quality of life burden on society. A population based study on self-reported symptoms gastroenteritis in Ireland estimated that there are approximately 3.2 million episodes of acute gastroenteritis on the island each year (Scallan et al., 2004). Although gastroenteritis is not always caused by food, foodborne gastroenteritis remains a substantial cause of morbidity and mortality. Evidence from studies worldwide suggests that foodborne illnesses most commonly occur in the household setting with a large proportion caused by cross-contamination and improper food handing (Worsfold and Griffith, 1997).

This study was undertaken to examine the level of knowledge about food safety and food hygiene amongst householders on the island of Ireland. The study also correlated food safety knowledge with the incidence of pathogens in the domestic kitchen.

A representative sample (1,020) of households across the island of Ireland participated in a knowledge survey and refrigerator investigation (microbiological and temperature study).
The main findings of the interviews were:

  • 42.5% of householders said it took more than 30 minutes (and in some case more than 3 hours) to get shopping from store to home refrigerator.
  • The majority of householders interviewed (>75%) did not know the correct temperature for refrigeration. Most did not possess thermometers for either fridge (76.8%) or freezer (71.5%).
  • 45% of householders reported storing meat incorrectly in the refrigerator.
  • When asked about handwashing practices, householders suggested that hands should be washed before meals (70%), after using the toilet (50%) and after handling raw meat (60%). However, 30-50% did not mention some or all of these, and very few mentioned that hands should be washed after feeding/touching pets, after gardening, after work or after changing a nappy.
  • After cutting raw meat, 23.6% of householders did not adequately clean knives, and 22.7% did not adequately clean chopping boards.
  • 57% of householders reported the use of unsafe practices to defrost frozen meat, with over half defrosting meat at room temperature.
  • One-third of householders reported the use of unsafe techniques to determine if meat was cooked properly.
  • Most householders had heard of Salmonella (92.9%), Escherichia coli O157 (77%) and Listeria monocytogenes (45.2%). Other pathogens, including Campylobacter, were relatively unknown.
  • Following swabbing of domestic refrigerators, the average total viable count (all live bacteria) was 12.6 million bacteria per cm2, whilst the average total coliform count (which could include Salmonella and E. coli O157) was 10,000 bacteria per cm2. The most prevalent potential pathogen was Staphylococcus aureus, which was present in 41% of all refrigerators swabbed. The incidence of other organisms was lower: E. coli (6%), Salmonella (7%), Campylobacter (0%), L. monocytogenes (6%), Yersinia enterocolitica (2%).