The effects of different hygiene procedures in reducing bacterial contamination in a model domestic kitchen

Abstract

AIMS: Few studies have compared the effectiveness of hygienic cleaning under simulated use conditions. This study compares commonly used and novel cleaning methods for food contact and hand contact surfaces in kitchens. METHODS AND RESULTS: We report results from two surveys on Norwegian consumers' cleaning procedures. Laboratory models involving cutting boards, tap handles and mobile phones contaminated with Escherichia coli and Staphylococcus aureus were used to compare the hygiene efficacy of commonly used cleaning methods together with new technologies (sprays, single-use wipes, and chlorine-based disinfectants). Commonly used cleaning methods produced a mean log10 reduction (LR) in contamination of 1·5-2·5. The efficacy could be improved by drying or including a disinfection step (mean LR 3·1-4·6). Cleaning of mobile phones was common and was improved by including humidity (1·5-1·9 mean LR). CONCLUSIONS: In many situations, traditional methods used by consumers may be sufficient to hygienically clean surfaces. However, in some situations, such as where there are infected or immune-compromised individuals, or where high risk foods are being handled, hygiene practices resulting in higher LR should be recommended. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that data from models simulating use conditions are required to estimate the effectiveness of detergent-based removal practices and how these can be enhanced by inactivation processes such as drying and disinfection to ensure that contamination from food-borne pathogens is reduced to acceptable levels to prevent infection transmission.