A PROTOTYPE POULTRY TRANSPORT CONTAINER DECONTAMINATION SYSTEM: II. EVALUATION OF CLEANING AND DISINFECTION EFFICIENCY

摘要

Poultry transport containers (PTC), when not adequately cleaned and disinfected each time after hauling live birds, carry the risk of introducing foodborne pathogens into the poultry processing plant as well as infecting subsequent batches of transported birds. In the apparent absence of a satisfactory system, we have evaluated a two-step decontamination process for cleaning and disinfecting PTCs using a recently developed, novel prototype decontamination unit. The PTCs were first manually cleaned with a high-pressure jet spray (6 MPa) of disinfectant solution and subsequently immersed in either hot water (24℃, 50℃, 60℃, and 70℃) or a sodium hypochlorite solution (0, 500, 750, and 1000ppm at an ambient temperature of 24℃). Both conditions (heat and chemical) were tested at 0.5, 1, and 2 min contact times. Salmonella and/or coliform counts were determined before and after pressure-washing and after immersion treatment. In the absence of large numbers of Salmonella, coliform counts were used to determine cleaning and decontamination efficiency. Pre-cleaning PTCs with a high-pressure jet spray of the disinfectant solution did not produce significant reduction (a = 0.05) in coliform populations. However, immersing pre-cleanedPTCs in hot water at either 60℃ or 70℃ reduced coliform concentrations an average of 1.6 logs (P < 0.05) within 0.5 min. Similarly, immersing the PTCs in a sodium hypochlorite solution at 1000 ppm for 2 min at a mean tank temperature of 28℃ significantly reduced coliforms by an average of 4.2 logs (P < 0.05). It was concluded that either heat or chemical treatments reduced coliform counts enough to reduce the risk of cross-contamination significantly. This prototype decontamination system can be further modified and is adaptable for use in poultry processing plants for cleaning and decontamination of PTCs.