Bactericidal efficiencies of commercial disinfectants against Listeria monocytogenes on surfaces

The efficiencies of potassium persulphate, isopropanol, hydrogen peroxide a nd peracetic acid, quaternary ammonium compound, hypochlorite, sodium dichl oroisocyanurate, ethanol and phenol derivatives, tertiary alkylamines and d imethyl alamine betaine-based disinfectants and a hypochlorite-based disinf ecting cleaning agent were evaluated against eight Listeria monocytogenes s trains representing three different ribotypes. All the disinfectants were e ffective in a suspension test with an exposure time of 30 s at the lowest c oncentrations recommended by the manufacturer. The efficiencies on surfaces were reduced. However, on clean surfaces all the agents were considered ef fective when the exposure time was 5 min and the concentration was the aver age recommended by the manufacturer. Five of nine disinfectants and the dis infecting cleaning agent were considered effective in soiled conditions in the such ce test. The most efficient agent was isopropanol-based and the le ast effective was the disinfectant containing tertiary alkylamine and dimet hyl alamine betaine. Differences in bactericidal efficiencies of disinfecta nts against different L. monocytogenes strains on meat soiled surfaces were found.