SUITABILITY OF A BIOLUMINESCENCE METHOD F OR EXAMINATION CLEANING ANDDISINFECTION IN FOOD-PROCESSING

The efficiency of cleaning and disinfecting surfaces was proved in the production line of a meat mincing plant, a fish processor and also in meat transport trucks. A bioluminescence technique was used to detect ATP from microorganisms and somatic cells. This method was compared w ith the results of conventional swab-methods. Examinations with known ATP- and microorganism- concentrations should reveal the sensitiveness of the bioluminescence method and show the correlation of microorgani sm-concentration and RLU as ATP-equivalents. These examinations yielde d results to judge hygienic conditions in the above mentioned plants a nd transportation trucks. Following results were found: The smallest d etectable concentrations for ATP are approximate 10(-14) bzw.(-15) Mol /test, for bacterials 10(3) cfu/test and for yeasts 10(2) cfu/test. Di fferent bacterial strains showed a correlation-coefficient between con centration and RLU of 0.93, while two yeast generas showed one of 0.95 . Appropriate cleaning and disinfection is indicated by RLU-levels sma ller than 100. On easy-to-clean surfaces, RLU-levels smaller than 100 can be obtained without problem. Surfaces which are difficult to clean should not exceed RLU-levels of 500. The employed bioluminescence met hod seems to be well suited for monitoring cleaning and disinfection b ecause not only microorganisms could detect but also organic soil.