The reduction of aerobic bacteria on chest, front leg and neck after high-pressure washing was 1.0, 0.86 and 0.68 log CFU/mL, respectively, compared with those before high-pressure washing (
Fig. 1). According to the previous study, it is not very effective on a small number of common bacteria, coliform, and
E. coli cells [
6]. Also coincide with other studies reporting that high-pressure washing with only water offers an extremely low bacteria reduction rate and even causes contamination on the surface of other pieces of meat [
2-
4,
7]. Moreover, the log reduction value was negative for flanks, which demonstrates that microorganism contamination increased after high-pressure washing than before. In the study that was conducted on a large-scale abattoir, the level of microorganismal contamination increased from 0.78 log CFU/cm
2 to 1.01 log CFU/cm
2, revealing that the method acts to redistribute the bacteria than to remove them [
8]. These results show the methods used in abattoir are not quite effective for meat hygiene. Therefore, the alternative methods using disinfectants should be considered. LC has 1.24-2.02 log reduction for aerobic bacteria (
Fig. 2). This coincides with the results of previous studies reporting that 2% LC sprayed onto beef head for 26 sec led to 1.52 log reduction in microorganismal count, with 2% LC sprayed on beef resulting in 1.6 log reduction in microorganismal count [
9,
10]. Moreover, 2% LC applied for 15 sec on meat inoculated with
E. coli was found to result in 1.5-2.2 log reduction in
E. coli count [
11]. Similarly, when LC was sprayed in the abattoir, there was a 0.9-2.3 log reduction in aerobic bacteria [
12]. Another study also reported an improvement in the storage quality of meat to which LC was applied [
13]. ClO
2 has 1.44-1.96 log reduction for aerobic bacteria. This is similar to a previous study reporting that when 10 ppm of ClO
2 was used, it resulted in ≥ 1.53 log reduction [
14], as well as another study reporting that when ClO
2 was used on chicken carcasses, significant reduction was found even at concentrations below 10 ppm [
15,
16]. However, when 800 ppm of ClO
2 was used on beef inoculated with
E. coli, the result did not exceed 1.3 log reduction in
E. coli count [
14]. The differences in reduction of this study compared to the previously mentioned may be due to different inoculation methods, as well as initial microbial concentration, contact time, type of fruit, disinfection system, disinfectant forms, and enumeration method. According to a previous study, application of ClO
2 for 1 min or less did not lead to significant reduction and this shows the importance of long contact time [
12]. SAEW has 1.1-1.91 log reduction for aerobic bacteria. According to previous studies, 20 ppm of SAEW resulted in 1.5 log reduction of aerobic bacteria, and 40 ppm of SAEW showed a significant reduction in mesophilic bacteria in pork meat [
17,
18]. However, when meat was treated with SAEW for 5 min using the dipping method, aerobic bacteria reduced from 3.06 log CFU to 2.28 log CFU [
19]. Free chlorine concentration is the most important factor that determines the sterilization effect of SAEW, it is most effective at pH between 6.0 to 7.5 [
20]. Therefore, the results may differ due to differences in PH caused by technicalities.
These results indicate that application of chemical disinfectants can be alternative method to get over high-pressure and time which is disadvantages of high-pressure water based washing. Results indicate chemical disinfectants show constant effects not greatly affected by low pressure and application time, and show higher decontamination efficacy than high-pressure washing method. The results could be serve as a basis for other decontamination methods on abattoir model.