Wessex shopping basket survey - a structured approach to local food sampling

The shopping basket approach to food sampling, in which ready-to-eat food items from a shopping list were sampled at premises chosen at random, was adopted by 15 Environmental Health Departments in the Wessex region. A total of 2037 samples were analysed over a 30-month period. The microbiological quality varied considerably between food categories, with gravy and stock samples giving the highest proportion of satisfactory results. Sliced meats, cooked rice and sandwiches gave the poorest overall results. Whilst the majority of unsatisfactory results were due to elevated levels of indicator organisms (Aerobic Colony Count, Enterobacteriaceae and Escherichia coli), unsatisfactory or potentially hazardous levels of pathogens (Staphylococcus aureus, Bacillus cereus, Clostridium perfringens or Listeria monocytogenes) were detected in 1% of samples. Salmonella was not detected in any sample. The shopping basket survey was considered to be a useful way of structuring local sampling, and the random selection of premises was found to be a considerable advantage over previous sampling plans. In addition, the survey drew attention to a number of microbiological problems with specific food types, leading to more detailed investigations.