Purpose: Identify the contamination by Salmonella, Listeria monocytogenes and indicator microorganisms in main steps along the pig slaughter in an industry located in south of Brazil to map the critical points of microbiological contamination.
Methods: Samples of pig carcasses were collected after different steps of the slaughter process (bleeding, scalding, dehairing, singeing, washing after toilet, evisceration, inspection, final washing and chilling), (n = 130). Detection of Salmonella was conducted using PCR BAX System and L. monocytogenes by VIDAS. Aerobic mesophilic (AM), E. coli (EC), total coliforms (TC) and Enterobacteriaceae(EB) were analyzed using 3M Petrifilm. The result was statistically evaluated through the ANOVA and Tukey test.
Results: Salmonella was present in 26.6% of carcasses analyzed in the initial stage and in 1.11% in the last step. Detection of Salmonella was heterogeneous, indicating that the presence of bacteria is dependent of several factors. Listeria monocytogenes was only detected in carcasses from the final wash (21.1%) and in chilling (8.9%). For indicator microorganisms statistical difference (P > 0.05, Tukey test) was observed between same steps for all the microorganisms tested. From beginning to the end of the process, reduction of 1.6 for AM, 0.7 for EB, 0.8 for EC and 0.7 log CFU/g for TC was observed.
Significance: The study was used to evaluate the microbiological performance of a pig slaughter industry in Brazil and establish strategies to decrease microbiological contamination.