Avaliação da presença de Salmonella spp., e contagens de Escherichia coli e microrganismos mesófilos aeróbios em carcaças de frangos de corte com e sem contaminação gastrintestinal visível na superfície externa

Abstract

The main risks to the safety of poultry meat products stem from gastrointestinal contaminations that occur on the carcasses during the necessary operations for the slaughter of broiler chickens, with this type of contamination being frequent on the carcasses during processing. With the aim of assessing the microbiological quality of carcasses that do or do not present visible gastrointestinal contamination on the external surface, 60 carcasses were collected, with 30 visibly contaminated by gastrointestinal content and 30 without visible gastrointestinal contamination on the external surface. The carcasses were collected at a slaughterhouse subjected to Federal Inspection, located in the metropolitan region of Belo Horizonte, Minas Gerais, which slaughters approximately 130,000 birds per day (10,800 birds per hour), in two shifts, using automatic evisceration equipment. Counts of Escherichia coli, aerobic mesophilic microorganisms, and the search for Salmonella spp. were performed. 1200 different colonies were isolated and cultured on Petri dishes with various culture media. The isolated colonies were sent for proteomic analysis, by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF), to confirm the genus and species of the microorganism. Carcasses with visible contamination on the external surface showed higher counts of E. coli and aerobic mesophiles (p<0.05); no significant change was observed in the profile of present bacteria (p>0.05). There was no difference in the prevalence of Salmonella spp. between the two groups (p>0.05). Among the main identified bacteria, E. coli, Klebsiella pneumoniae, and Citrobacter freundii stood out, present in 95%, 85%, and 81.7% of the carcasses, respectively. It was concluded that carcasses with visible contamination have a higher count of aerobic mesophiles and E. coli, demonstrating a greater risk of transmitting pathogens associated with foodborne illnesses (FBIs) to the consumer.