Sustainable Practices and Microbial Quality of Cattle Offal in Slaughterhouses

As global income levels and population increase, meat consumption and production are rising, raising concerns about climate change, animal welfare, and environmental sustainability. Offal offers a sustainable, nutrient-rich, and economical alternative to muscle meat, providing proteins, vitamins, and minerals. This study was triggered by the scarcity of information on the microbiological quality of edible bovine offal, which is often associated with poor hygienic conditions during handling and processing at slaughterhouse. This study assessed the superficial microbiota present on cattle liver and tongue in a vertical slaughterhouse across various stages of the procurement process and on days with different slaughter volumes, with three sampling points: immediately after post-mortem inspection (Point 1); after the arrival of the viscera in the preparation room (Point 2); and in the refrigeration chamber at 3 degrees C (Point 3). Samples were analysed according to ISO methods for enumeration of mesophilic aerobic bacteria, Enterobacteriaceae, generic Escherichia coli, presumptive Escherichia coli O157, and Staphylococcus aureus and detection of presumptive Escherichia coli O157, Staphylococcus aureus, and Salmonella spp. Microbiological counts were within the acceptability values stipulated in the amendment of Regulation EC 1441/2007 to Regulation EC 2073/2005 for cattle carcasses. In general, both viscera showed higher microbial counts on days with higher slaughter volumes, with the exception of Enterobacteriaceae and Staphylococcus counts on the tongue. There was also an increase in microorganism levels across the offal processing stages. Out of 144 samples, 20.83% were contaminated with presumptive Escherichia coli O157, 3.47% Salmonella spp., and 25% S. aureus. Therefore, although 20.83% of the samples tested were presumptive for E. coli O157, it is important to note that a considerable number of these presumptive positives may in fact have been negative after confirmation by molecular methods. However, the presence of presumptive E. coli O157 at high levels is one reason that the prevention of offal contamination requires more stringent measures. Preventing offal contamination requires stricter measures during slaughter procedures to ensure safety, reduce food losses, and enhance sustainability in meat production.