Hygiene monitoring in poultry meat production - Use of bioluminescence ATP assay

A bioluminescence ATP assay for hygiene monitoring in poultry meat production was evaluated using 232 samples. To obtain the bacterial ATP level and colony forming units (CFU) of poultry 25 cm(2) poultry breast skin and 10 g poultry neck skin samples were examined. Samples were excised during the slaughter process: (1) before the body was opened, (2) immediately after evisceration, (3) after the carcass entered the inside-outside-body-washer, (4) before the carcass entered the air-chilling room and (5) immediately after the carcass left the air-chilling room (before carcass weight classification). Additionally, at 4 degrees C, aerobically stored carcasses were investigated on the 3rd, 4th and 7th day after slaughter, respectively. From all samples, ATP was assayed and total viable counts (psychrotrophic and mesotrophic bacteria), Pseudomonadaceae, Aeromonas and Enterobacteriaceae were obtained by drop plating method. The detection limit for the ATP-bioluminescence method for mesotrophic bacterial ranged from log 3.5 to 4.5 CFU/cm(2) in poultry breast skin. Using samples from neck skin the correlation coefficient of 0.51 was calculated between the ATP assay and the amount of total viable counts. For poultry breast skin, the overall correlation coefficient was calculated as 0.86. According to our results the ATP bioluminescence method is to be recommended for detection of total microbial load in poultry within the framework of internal hygiene monitoring. In the evaluated premises as mentioned above microbiological guideline for total bacterial counts 3.8 log10 CFU/25cm(2) and for Enterobacteriaceae 1.7 log10 CFU/25cm(2) are to be recommended. An RLU value of log 1.8 is equivalent to these microbiological guidelines for monitoring the poultry production process.