The effect of ozone on bacterial contamination of poultry carcasses at an industrial slaughterhouse in Tehran

Survey on bacterial contamination is one of the most important ways for hygienic evaluation of meats at different points of processing and marketing. In the last decade application of ozone as an antiseptic agent was proposed in foods (meats, vegetables, fruits, etc.) processing. The aim of this study was to evaluate the effects of ozone gas for reduction of bacterial contamination of poultry meats at an industrial slaughterhouse in Tehran.

In this study, 210 whole chicken carcasses in 7 groups (one control group and 6 test groups) randomly were selected and exposed to ozone gas with various concentration of 4, 6, and 8 ppm, and exposure time of 4 and 10 minutes. Standard methods were used for total bacterial count and detection of Salmonella in the samples. Data were analyzed using descriptive statistical indices and ANOVAs test.

The results showed that the mean of total number of bacteria in the control group was 1.02×105 cfu/g while in the test groups with two exposure times of 4 and 10 minutes consisting of groups; with the gas concentration of 4 ppm were 9.14×104 and 1.76×104, with the gas concentration of 6 ppm were 3.51×104 and 1.15×103 and with the gas concentration of 8 ppm were 5.32×102 and 1.06×102 cfu/g, respectively. There was no Salmonella bacterium in the samples of the test groups of 8 ppm gas concentration with both exposure times of 4 and 10 minutes.

The results of this study are indicated that application of ozone as an antiseptic agent on poultry carcasses at slaughterhouse has a proper positive effect on microbial load reduction of the meats.