Effects of slaughter operations on the microbiological contamination of broiler carcasses in three abattoirs

- A microbial process analysis of poultry carcasses was performed in three abattoirs.
- Reductions of the microbial loads from delivered broilers to chilled carcasses.
- Total viable counts, Enterobacteriaceae and Escherichia coli reduced until after plucking.
- Campylobacter counts mainly constant during slaughtering (increase after plucking).
- Clear differences between Campylobacter counts of the abattoirs after scalding.

Broiler carcasses from three abattoirs were examined at selected stages of slaughter for indicator bacteria and Campylobacter spp. (pooled neck and breast skin samples). Before scalding, total viable counts (TVC) and Campylobacter counts from carcasses (n = 48) averaged out at 7.7 log CFU/g and 3.6 log CFU/g, respectively. After scalding (n = 90 at this and the following stages in each abattoir), mean values from the abattoirs ranged from 6.0 to 6.5 log CFU/g for TVC and 2.3 to 3.3 log CFU/g for Campylobacter. The abattoir-specific differences were probably related to varying scalding parameters (temperature/time exposition). Plucking reduced TVC (on average by 1.5 log CFU/g), whereas Campylobacter counts slightly increased. Enterobacteriaceae/Escherichia coli counts from plucked carcasses of the three abattoirs ranged from 2.9 to 3.3 log CFU/g. After evisceration, washing and chilling, minor changes occurred, albeit certain abattoir-specific effects were evident. In the chiller, mean TVC, Enterobacteriaceae/E. coli counts and Campylobacter counts from the abattoirs ranged from 4.2 to 4.4 log CFU/g, 2.8 to 3.5 log CFU/g and 2.5 to 3.4 log CFU/g, respectively. Such abattoir-specific data form the basis for implementing targeted and sustainable measures at selected stages of the poultry slaughter process (cost-benefit analysis).