Efficacy of ozone treatment to eliminate Salmonella enteritidis from eggshell surface

The bactericidal effect of saturated ozonated water against S. enteritidis inoculated on eggshell surface was evaluated. The results showed that conce ntration of 1.4 mg ozone/L at 22 degrees C for 30, 60, 90 s of ozone flushi ng time at a given time flow rate of 100 ml/min, caused a decrease of S. en teritidis population estimated by 1.02, 1.19, and 1.37 log units (mean valu es), respectively. At 4 degrees C ozonated water temperature (ozone concent ration 3.0 mg/L), the decrease of the S. enteritidis populations after expo sure time of 30, 60 and 90 s, was 2.12, 2.34, and 2.47 log units (mean valu es), respectively. The percentages of bacterial death reduction at 22 degre es C or 4 degrees C were 90.0%, 92.2%, 95.1% or 99.2%, 99.5%, 99.7%, respec tively, while in the control samples the analogous values were 50%, 59.8%, 62.3%, or 53.3%, 58.3%, 61.6% respectively.