MeatCulture: microbiological, hygienic and qualitative profile of bovine fifth quarter viscera

The MeatCulture project aimed to improve the quality and safety of bovine fifth quarter viscera (tripe, intestine, lung, and trachea), which are traditional dish ingredients in many communities. Stabilization studies were conducted on tripe and intestine samples, and preservability studies were conducted on lungs and trachea. Tripe samples (24 across two batches) underwent washing and bleaching treatments with different temperature-time combinations, then they were vacuum-packed, stored at 2±2°C, and analyzed at various timepoints. The pH was determined, and the Enterobacteriaceae count and the presence of Salmonella, Listeria monocytogenes, and Yersinia enterocolitica were investigated. Results indicated that applying a washing step at a temperature range between 55°C and 65°C for 2 minutes, followed by bleaching at a temperature range between 58°C and 70°C for 2 minutes, preserved stable pH (T10: 7.24±0.06) and controlled Enterobacteriaceae counts, which decreased at T7 (2.78±0.48 CFU/g) before slightly increasing at T10 (3.24±1.55). Pathogens were never detected. Part of the small intestine (jejunum) and colon samples were vacuum-packed (30 samples overall), subjected to four types of heat treatments, stored at 2±2°C, and analyzed at various timepoints. pH and microbial profile were evaluated as previously described. The treatment with water at 70°C for 15' showed the best results with Enterobacteriaceae counts below the detection limits in most samples at T10. The lungs (153 samples) and trachea (81 samples) samples were packaged with CO2 and N (ratios of 50/50 and 70/30) modified atmosphere packaging (MAP). The samples were stored at two different temperatures (2±2°C and 8±2°C) and analyzed at various timepoints. On each sample, pH, aerobic colony count, Enterobacteriaceae count, mesophilic lactic acid bacteria count, and Pseudomonas spp. count were evaluated. The microbial profile of the samples stored at 2±2°C and with the 50/50 MAP showed lower average values.