Comparison between ATP BioluminescenceTechnique and Traditional Microbiological Method to Detect Contamination within Food Facilities in Saudi Arabia (Jiddah)

Abstract

Food-contact surfaces are potential sources for the transmission of foodborne pathogens. Thus, it is important to eliminate bacteria by using proper sanitizing methods in order to reduce cross-contamination during food preparation and/or consumption. The objective of this study is to determine the level of contamination within certain food facilities in Jiddah, Saudi Arabia, using the traditional microbiological culture (aerobic plate count) and the ATP-bioluminescence assay methods and to establish if any correlation exists between the conventional direct surface plating and an ATP reading. Different samples obtained from food processing surfaces (sampling point) such as a cream mixer, cutting boards, an orange squeezer and knives at the salad section, and also a marble worktop at the pastry site were examined. All samples that were taken from the food processing equipment/surfaces showed high levels of contamination before the cleaning stage, but reduced sharply after cleaning and sanitizing. The correlation coefficient (R) values between the traditional microbiological culture (aerobic plate count) and the ATP-bioluminescence assay methods were in the range of 0.72 - 0.99 after the cleaning stage for all the samples, whereas before the food preparation equipment/surfaces had been cleaned, the R value was very low; this is possibly due to the differences between the two detection methods. The ATP-bioluminescence assay method can detect the presence of food debris, and this was translated to a high number of Relative Light Unit (RLU) indicative of a high level of contamination, whereas the traditional microbiological culture (aerobic plate count) method can only detect microorganisms. Therefore, the correlation coefficient (R) values after the cleaning stage have shown to reach a high value of 0.72-0.99 in all the samples due to the removal of food debris during the cleaning stage. Moreover, the results indicate that the ATP-bioluminescence assay is a good tool for monitoring the cleanliness of surfaces and hygiene practices at food premises.